Oil pressure issue traced to non-matching head, cover and bearing caps

First let me acknowledge that I am acutely aware that I should have sprung for that Pre Purchase Inspection. I knew this going in yet at the moment it really mattered I somehow justified skipping that step. I am paying dearly for that little mistake so no need reminding me that this was all avoidable if I had just....... OK so here's my story. Bucket list item was to own a Porsche but I live where there really aren't many so I found what I thought was a great prospect on-line near where my brother lives. After I made the deal he shipped it to me. Almost immediately I realized that after the engine gets to temp it loses most of it's oil pressure. within a few days on a cold start I heard crunching so I immediately shut it down. I had it towed across island to the only competent European car shop on this island. They said the crunching was either the guides or pads that became collateral to the low oil pressure problem. That in and of itself wasn't the end of the world but the low oil pressure might be. All the little stuff was ruled out so it came to down to the conclusion that it was something deep in the engine. They said at their prices I would be way better off either getting someone else to rebuild this motor or to just get another motor and swap it out. So I had it towed back to me with the engine out and on a pallet. I quickly realized that the car would sit and probably rot before I would ever be able to spring for a rebuilt engine - given cost with shipping to Hawaii. Perhaps it would help to note here that I am simply not willing to pour endless money into a car that I'll never get back out of it. As I said, this was a (rather dumb in hindsight) bucket list present designed to be however I could best 'blow' 10 grand. (Boy did I excel at that!) My promise to my wife while selling her on my extravagant purchase was that I would just drive it until it died and would not let it be a cash drain on us since we are of modest means. Obviously I thought I'd be able to drive it at least for awhile so am simply trying to figure if there might still be a way.... Anyway, since I have found myself with nothing but time lately (thanks to lockdowns and furloughs), and I figured I didn't have much to lose, I have spent the last several weeks tearing the engine down. It turned out to be an amazingly fun way to pass the time! I'm not sure it will ever run again but just in case I have been meticulous in taking detailed notes and photos, and labeling and bagging everything. If it does get to that point I figured I would have someone competent do the hard stuff in getting it back together. So as I progressed with the tear-down everything looked beautiful inside all three oil pumps, as well as with everything on the left side (1-3). But as soon as the valve cover came off the right side (4-6) I could tell this was where the problems were. Everything was much darker in color than the other side, and there was gunk around the bearings and cylinder #6. I could also see some wear on the bearings. Not much, but enough that you know it hasn't been an entirely smooth ride for the camshafts. Upon closer inspection I discovered that all four numbers were different! As I'm sure you all know, the cylinder head, valve covers, and both camshaft bearing caps are machined together and must match. Well I have four different numbers! A 10 year old invoice for the rebuild 55K ago reveals a new cylinder head but not the other parts. Somehow at least three of those parts were replaced with no regard to matching numbers. So much for the quality of work out of that SoCal Indy Porsche shop!!! I have read in Bentley and on many forums that the numbers must match or problems such as low oil pressure will occur. But not much has been written about solutions once you discover that has already happened. I didn't see new ones on Pelican parts although obviously (given the above paragraph) I wouldn't be willing to buy them new if they were due to cost. I have a call into a scrapper to see if they can come up with a matched set but haven't heard back. I did find new cylinders but no matching sets, making me wonder how important this really is? I did find one additional anomaly - a small piece (1/2"x 1/2" ID) of rubber hose sitting (not lodged) in the bottom-most oil well of that side. I'll include a photo but it is below the scavenge pump. So FINALLY, here are my questions. Thanks for your patience in getting here! 1- Do I have agreement that this mis-matched cam bearing issue is where my low oil pressure was coming from? (Remember a competent garage verified it wasn't the stupid little things such as the pressure relief valve, the gauge, the pressure switch, a collapsed filter, etc, etc. etc., so while I appreciate it, save your typing fingers on those possibilities. They said it was definitely caused by something inside the engine!) 2- Is there any other way to resolve this short of replacing all these parts? Can they be re-machined? Remember that I'm not trying to build a race car here. I'm trying to find a way to squeeze a few miles out of a car before I give up on it and scrap it! 3- As for the piece of hose - no doubt it didn't help but does anyone think it could have been the only thing causing the low OP issue? Boy wouldn't that be a dream! 4- I have found the source of the crunching - lower guide on right side. But despite having both heads off and most everything else off the engine, I can't figure out how to inspect, let alone change, the guide for the primary chain that runs between the crankshaft and the intermediate shaft. The shop indicated all guides could be changed without cracking the block. True or not? If so, please describe how. I can't find anything written on it - even in Bentley! 5- Could somebody convince my wife that it's OK to keep pouring money into this car? I mean -it's a Porsche for goodness sake! Two of the non-matching numbers. The head and valve cover numbers are both different as well. Notice the dark color of everything this side of engine. looks decent underneath Here is the little piece of hose I found sitting (not lodged) it this well. Before I picked it up. roven wrong!

Yes, the head , cover , and caps should all have the same number, this keeps the guess work out of it ( matched set). Now that you know they are not matched, you must get out some high quality micrometers to measure the clearance too if it is infact a reason for low oil pressure. You measure them all and compare to the "matched" non-worn side. And measure the cam journals and you can subtract for a clearance value. And yes they can be re-matched/machined and renumbered, but not a common or simple procedure. The guide you're talking about between the crank and IMS will need the cases split to replace. While you got the cases split, go ahead and check the main and rod bearings, and measure the cylinders for taper/out of round. And buy Jakes video on assembly and disassembly, all the novices say it really helps with firstimers to keep from making costly mistakes.

Lost, where are you, Big Island? What shop have you been dealing with? I'm on Kauai and have a motor running strong in my car that I drive daily. It will be for sale in March when my new motor arrives. You'd be second on the list. Another option would be to buy a used Boxster motor to get it on the road cheap.

Buy a good used matching parts head and put it all back together. Yes, the 2 long chain ramps come out when the heads are off. Look for the bolt on the side of the block. They have big round flat heads. The only chain guide you can't get out without splitting the block is the one that wraps around the intermediate shaft. Sine the engine wasn't knocking, the main and connecting rod bearings are probably still ok.

Thanks to all of you for some good info. - I now know that I do have to split the case to get to the curve shaped guide. This is contrary to what my local shop said but I suspected as much after getting down to just the case and still not being able to see it. I had already removed all the other guides and this was the last one I need to eyeball for damage so thanks for clearing that up for me. - Should I ever be putting this thing back together, I will indeed buy Jake's book as I'm sure it will provide that extra security I will need in doing so. - Buying another replacement engine and having it shipped over has always been an option. I hadn't considered looking for a local Boxster engine but I know they are usually much cheaper and if it is local wouldn't require shipping so I might look into that if I can't resolve this any other way. I wouldn't really care if it was a lesser engine. I would just really like to drive the car again! Anybody know how much converting there would be to get everything hooked back up right? - To 808Bill- I appreciate the offer but I just don't see myself springing for whatever you will likely want for a decent working 996 motor and then shipping it to BI. Still, if I haven't done anything by March you never know so do let me know if it does become available and for how much. But like I said, I'm not a likely buyer of that. - I guess what I am really hoping is that eventually I will run into someone who has a blown M96.04 motor lying around with no damage to the right side. I have read several times that most catastrophic failures take out the left side than the right so right sides are easier to find. Then hopefully that nice someone would pull and send me just the matching numbered head, valve cover and bearing caps that I need so I don't have to pay to ship the whole motor over. - In the meantime I might see if any machine shop here might be able to re-machine these at least better than they are. I don't know for sure, but according to the records I received with the car the engine doesn't appear to have been out for ten years and 55K miles. I do know for sure that the head change was back then so presumably all the mismatching was done at that time. So I think I can deduce that it did run OK for awhile with these mismatched parts so maybe I can get them good enough to run awhile longer. I dunno. Might at least be worth taking them in and - as we say here in Hawaii - "talking story". Thanks again for the responses so far. I do appreciate your opinions and ideas so please keep those cards and letters coming! Aloha

Careful on diagnosis.....crunching sound...Maybe you should take a look at your intermediate shaft bearing,and not focus so much on your cam caps,by the way even if mismatch the don’t physically look to bad.If you haven’t done so already you should look in oil filter canister and drop sump plate to see if you have any debris.regards p.s my brother lives in Pa Pa bay

Quotes source post: 16935575

My Boxster S engine with a somewhat recent LN IMS bearing and 100,000 miles was $3,000(or $3,300 maybe) a few years back when I swapped it in. Not much for other costs except for �while you�re in there� type stuff. The only real pain is drilling and tapping a bunch of m6 Holes in the heads of the Boxster engine for the intake manifold and exhaust hangers- the bosses are on the Boxster head but they are blank and not drilled/tapped. I also think you want to try to get a Boxster engine that�s running the same version of Motronic as you 996. And you can make a little coin back by selling the boxster s exhaust manifold, throttle, and maybe some other little parts from the engine depending on what your engine comes with. I would not personally go with anything less than the 3.2. The 2.7 or 2.5 would be pretty uninspiring I think. I originally put my 3.2 in thinking it would be temporary but so far it�s been plenty quick so I have Not been clamoring to upgrade.

Re installing the heads and putting it all back together is not that difficult. Don't let the size of the job scare you. Just do it one bolt at a time and eventually it will be finished. There is enough info here or buy the book, and put it all back together. The worst thing can happen is that it won't run BUT it doesn't run now either so what do you have to loose?

any reason you cant just buy one used head with cover?

Addressing the newest comments: - It's not the IMS. It was upgraded and shows no sign of wear. But thanks for the suggestion. - Inside the sump and filter were checked long before the engine was pulled and torn apart! . Much plastic debris was present in the sump (see photo) but nothing in the filter (yes I cut it open). According to the shop and others I have consulted the debris appears to be from two sources. I can see one of those - the damaged paddle shaped guide behind the oil pump - although I have not yet removed it. I can clearly see that it has seperated and part of it is gone, but it's too deep in there for a good photo now. I'll remove it next week and photo then. . But there are also curved pieces of debris that is believed to be from that curved guide above the main chain. That was why I was asking about access. I will have to get in there before I can determine full extent of damage. After the crunching I only started the car a couple of times (never drove it again) and it still ran smoothly - like nothing happened. So I continue to believe the collateral damage to the guides can be fixed. It is the low oil pressure that must be resolved. - I would love to find out that something else is responsible for the low oil pressure besides the mismatched head, cover and caps. I haven't found any better explanation but I'm all ears so have no problem with other thoughts. - As for Quadcammer's question: No - there is no reason I can't just buy another head and cover. I just haven't found a way to do that and what I have found (non-matching "ala carte" options) have been ridiculously expensive. That's why I mentioned I had called a 996 salvager - in hopes of finding a matched set. No luck yet. If you know a source for new or used matched sets please let me know! From what I understand all four pieces need to match. Here's what came out of sump

Quotes source post: 16936626

Thanks for the confidence booster. I'm pretty confident of the top end but but what about the case? Looks like I now need to open it to chase that elusive damaged guide above the IMS but am nervous about putting it back right. But you were right in that the worst that can happen is that I am right where I am now! But this possible outcome is exactly why I am not in favor of spending a bunch of money on this DIY project! The whole idea of the DIY was to try to get it done inexpensively. If I can't do that I'd be better off just sitting until sometime in the future when I can maybe spring for a rebuilt that I know will work right when installed!

Aloha! I too bought a 996 earlier this year with out a PPI. Had the same conversation with my wife. My first Porsche and 911 and a dream I didn't think I'd be able to achieve. There were title problems for months, the seller is here on Rennlist. The car was throwing codes right off the trailer in the parking lot. I got that sorted out and with in 1000 miles of driving it the clutch went out. The PO said he put a new clutch in. So I took out the transmission and replaced everything between the engine and transmission. Then with another 1000 miles on the clock the coolant leak became apparent. I chased it for weeks. All and all i put another $3500 into it in 9 months. I've been able to drive it 3500 miles now. I feel like I have it sorted at this point. These are complex machines and they come with a price. You seem like you have a good grip on getting the engine apart up to this point. Great write up and pix. It looks like you have tools, a garage, knowledge, and some time. You also have the folks here on Rennlist as a resource. I would encourage you to keep on task and dig in. It is very daunting and upsetting to have the car and not be able to drive it. Not knowing what could rear it's ugly head. I'm glad I didn't have this level of engine problems. I'd be freaking out too. Today my wife and I drove the car to get hot dogs across town. She has started to enjoy it and I'm glad. We were on BI in January just before the rona thing hit. We have friends on Oahu and have a heart for the people. Breaks our hearts to see the food lines. I think it's great you made the effort to get the car out there. I think you can pull this one off. Be encouraged!

Here is the first damaged chain guide. It is the bottom one on the right side.

How many miles are on this engine?

The car and engine have 165K miles on them. However, a complete rebuild of the motor was done in 2010 at 110K. According to the attached photo of the receipt, two rail kits were included. But given that this is when the mismatching of the head, cover and cam caps occurred I question their competence or honesty. So who knows if these rails had 55K or 165K on them!

Any damage to the chain that was sliding on this? Anything that looks like a chainsaw chain?

No. The chain is very clean. See photo. After I split the case I will be able to get to the curved guide above the main IMS chain, which is where the shop believes most of the debris came from. That is the chain that they were worried about.

What made them think it was the intermediate shaft chain pad that and not the ramps that you have in the picture?

Cool. Great to see your progress. My guess is that whoever did the rebuild simply didn't know what they were doing. They got it out the door and it ran for a time. I think you're doing a great job. Keep plugging away at it and showing the updates!

Here is another photo of debris found in the sump. From this angle the curved piece is clearer. It is that curve that other folks have tied to the main IMS-to-crank chain guide. That curved piece also doesn't match up with the damaged guides that have already been removed. In anticipation of the next question - let's talk about that little piece of metal that looks like a mini cotter key. Does anyone recognize it? So far no one that I have showed it to (including the shop) have any idea where it came from. At least one said they question if it even came from this engine. Truth is I never saw it in the sump. I first noticed it a week later, well after everything had been moved to another bin. So I suppose it could have been introduced there but I still don't recognize it from anything else I was doing so it just remains yet another thing I am keeping in mind while contemplating the future of this engine and therefore the car! I am very appreciative to have you guys helping me out and providing moral support too!

Yup, the curved one is from the intermediate shaft pad. Those are some large chunks, things came apart quickly.

I'm wondering if that "cotter pin" started its life a different shape and only looks like a cotter pin because it has been run through an engine and crushed in process. Based on the reflection it looks rounded vs. flat, so if that is the case it wouldn't be a crush washer. Experts - is this a circlip?

With that much plastic debris, I would say your lose of oil pressure was probably due to the pick-up screen blocked with that debris, instead of the miss-match of head/cover/caps (since you don't really know the true clearance values of those miss-matched components, they could be a good match or tight or loose). Since you had a low oil pressure issue, I would have a good look at the main and rod bearings..

Quotes source post: 16952934

You might be right. That inspection will come next since I now have absolutely everything removed from the block. So tomorrow or Saturday I will try to get the 4-6 side block cover off to see what else might be going on. In the meantime and related - should there be play in the IMS once the bearing covers are removed? As I said, everything is now off, including from both sides of the IMS - the oil pump and long Allen key on one side, and the IMS bearing cover on the other. Now I can wiggle the whole IMS from either side. Is that normal? I would have thought the bearings would hold it tight, not just the covers? See photos. I tried to show movement ability. Thanks again to all for your helpful comments and encouragement!

normal..

Loving the pix, conversation, and progress.

Quotes source post: 16952870

Perhaps, but the way it is folded over and not broken makes me think it might not be. I would expect it to break before folding over. They're very VERY hard and rigid. Very difficult to even compress a little bit by hand. If you grb it with pliers and bend it open even a little bit, it's not a wrist pin circlip.

Quotes source post: 16955076

It is not a wrist pin circlip. I inspected both items and the piece of metal I found is much smaller diameter. It is also not a cotter key either as it is too hard of metal for that. So I'm beginning to lean toward the theory that it came from elsewhere but would sure like to know for sure therefore I'm all ears to other ideas!! I'm now inside the case! Yikes! Anyway, stay tuned for photos and more questions! Love you guys!

So I got to the inside of the case today and am very surprised at how clean everything is - including the chain guides that I expected to be damaged. I found no chain wear on any part of any visible chain. I still can't see the bottom half of the main chain or that side of the guide but I can look through from the top and it just all looks really clean. Not even any sign of debris. So I don't really think I have problems down here. A few abnormalities that I did find: - A bolt loose inside the engine! See photo. It is about a 2" Allen bolt that was just sitting in the well under the right side IMS chain. The bolt was undamaged but how it didn't cause havoc will remain a mystery. Note the loose bolt under the chain Chain moved to show undisturbed bolt. As a side comment - this gives me great confidence because if the shop did this, along with everything else wrong we have talked about - yet it still ran for 10 years - I KNOW I'll be able to get this thing going again because I'm BOUND to do a better job than they did!!! - A totally clogged tube on one of the oil/air separators that are inside the sump. See the photo. It is packed tight. It must have been so clogged that it wasn't flowing because the "joint" between the top and bottom piece was blown out - broke the plastic out. Here is the very clogged sump air/oil separator. Look carefully at the top edge and you will see it is broken out. The debris appears to be more of the same material. I will also include a bunch of random photos now that the case is open and encourage others to look for issues that I'm not seeing. In the meantime, here are some things I need to ponder in my quest to get this thing revived with as little $$ as possible. (If in question about that, please refer to my opening arguments. Trust me when I say our personal financial situation ain't getting any better as we are now on month eight without tourists, which is what our family business depends on. So at the risk of redundancy, my objective here remains to see if there is a way I can get a little more life out of this car without much expense besides my own labor, or should I part it out instead. I swear (Jake, are you listening?) that I have no intention to sell this car to some unsuspecting person. That's what happened to me so I know how that feels. It's not my style and it wouldn't work too well on a small island to screw someone like that so no, it will not be sold. I will either keep it for my own use and then leave it for my next of kin if it's still running, or part it out if it's not. With that said, I'd appreciate some of your thoughts on what I should do. To Ponder: -What was the cause of the low oil pressure? The worst thing would be to put it back together and it still has that same issue! So was it the mis-matched items that remain the title of this thread or was it something else like the clogged oil separator tube just revealed? There was also a piece of rubber tube and that screw, both loose inside the engine. And let's not forget the scavenge pump that had lot's of tiny debris wedged in it making it almost locked-up. How do I know??? - If the main chain guides are not damaged as expected, where did that curved piece of debris come from? The only damaged parts I have found are two of the four long guides over and under each of the IMS to cam chains. As shown previously, one was very damaged - the top section just came loose is large sections. One other had just a bit of similar damage. One on each side was damaged, the other was OK. One top, the other side bottom - so no consistency. - I do not believe I have recovered nearly as much material as is missing from the two guides. So where did it go? Possible some just got eaten to bits but seems more likely to me that I am not the first to remove debris from the sump! - Because of this, my latest thought is that the PA (previous A-hole) had a similar crunching experience, took it to the shop and they told him he would have to have the engine done again so he just dumped it to some unsuspecting idiot - me! If that is the case - that my crunching was not the first crunching, then maybe the low oil pressure is a result of the debris stuck in the separator tube after the guide failed the first time, rather than the other way around. Problem with this handy scenario is that it still doesn't explain the curved debris and where it came from. OK, so if we can figure out the oil pressure issue so I'm fairly sure I won't be facing that again, please help me determine what HAS to be done from here in order to get this thing running again. Mahalo to all.

I am really really impressed by the work you are doing here. You are an inspiration to anyone. Your patient investigation and clear communications are outstanding. You are either fearless when going into projects or already have a good grasp of things mechanical. Many kudos. I will offer the same encouragement that others have to continue on the journey step by step. Not that this gets fixed through consensus, but based on the evidence, it seems the clogged screen and other restrictions are what lead to lost oil pressure. At this point it seems that a million measurements are in order to assure that the reassembly will work for quite some time. Teachings from Jake say you should focus on the quality of the ferrous coatings on the pistons. Also, have your injectors checked for leakage. It seems these are the major factors in the lifetime maintenance issue that turns into bore scoring. Hopefully both are OK. Good luck. I hope it goes together well and you can get back to the smile we all have when bombing around in these cars!

I think with all that "missing" debris, you've got to make sure you do a thorough cleaning of the block & heads to be sure there are no blocked/clogged oil passages (same goes for water, but it seems you didn't have a problem with that). I think that clogged swirl pot is at least one of your main problems, it's sort of a small miracle that the bolt didn't get caught up in that chain at some point in 10 years. Maybe some of those curved black plastic pieces are from that swirl pot? Also, as Porschetech3 pointed out, make sure you check the main crank and rod bearings as well as the crankshaft itself for damage. It looks like you're doing a very thorough teardown & investigation, so don't go too "cheap" on the re-build (I realize the finances are stretched, but there's no sense in throwing good $ after bad...). I hope you have a good outcome given the circumstances. Good Luck!

Maybe some of those curved black plastic pieces are from that swirl pot? dporto you are a genius! My mystery curved piece exactly matched up to the broken chunk off the swirl pot. Thanks for solving that mystery so that I can focus on other things! golock911 and dporto - thanks so much for your input and emotional support! You give me confidence to keep going! Truth is I have never done this before. And even though I have a business background (nothing mechanical), I do believe I am mechanically inclined. I spent months researching the job before starting, and continue to use whatever resources I can as I go along. (To that end - why is there NOTHING on the lower end?? Is Jake's $650 book the ONLY thing out there? I already sprung for bentley but it is silent on the lower end!!! Help!!) Anyway, thus far on this project I have taken probably 2000 photos, filed by the date taken, along with a notebook with meticulous notes of each days motions. I photo every nut and bolt as it is removed from the hole it came out of, then ziplock bag it and clearly label and date each baggie. I now have over 100 ziplocks in a large sealed container, filed by date, for safe keeping until needed again. I have also kept a parts list as I went along of any little items that could be forgotten, like bent fasteners or needed new gaskets or o'rings. The whole idea is that if this project takes a few years to complete I would still be able to get it back together without having to rely on my memory. In theory at least, I can just work my notebook backwards!

Dude, you rock. Aloha

In short, yes Jakes dvds r the only highly detailed totorial for building one of these motors at home. His experience will save u much more then the $650 for the vids.

It's been nearly six months since I updated this thread so I thought I'd wrap this one up for anyone that cares. Cutting to the chase - Great news! My 2000 996 is now running beautifully! Purrs like a kitten! I waited until I had 500 miles or so on it after the work to post this because I wanted to be fairly confident about the engine work before I started bragging about it! If you remember - or just read- my long sob story you must be wondering how in the heck I went from being down-and-out in my last post to happy as a clam now! So let me fill in a few of the details. When the thread died off, I had my engine totally apart and was still uncertain if the mis-matched numbers of the Bank 2 cam covers, head and valve cover were the source of the low oil pressure and was therefore uncertain of which way to go forward. I took about a month to ponder this. (If I do say so myself, one of the smartest things I did during this entire process was to NEVER be in a hurry!!) Case in point: After much contemplation and weighing of costs vs benefits vs risks, etc., the answer of how-to-proceed finally became clearer to me. Everyone believed that the damage was collateral damage to the low oil pressure problem. But I had every (or certainly most) invoices from the cars beginning and in reviewing them in detail I couldn't get past the fact that never once was their any mention of an oil pressure issue or concern. So I became more and more convinced that those mis-matched parts were not going to be the source for the oil pressure problem. I became convinced there was a previous 'episode' of the crunching up of the paddle and resulting debris found in the sump. I more I thought about all the facts I had in front of me the more I was willing to plant my flag firmly in the belief that the first 'episode' happened prior to my receipt of the car and it was during that first episode that the debris clogged the Air / Oil Separator, and was THAT, not the mismatched head, causing the oil pressure issues that I was experiencing. I came to believe that my 'episode' was not the first. After this month of contemplation I decided that my best course of action going forward would be to replace just the broken parts, along with seals and gaskets and things, just to see if it still has the oil pressure issue. I had enough confidence in my theory that I didn't want to spend thousands to replace a mis-matched head that I no longer believed was the cause of my problem. But I didn't have enough confidence to replace all kinds of other stuff that many suggested should be replaced as part of this process. I thought it was just as likely that I would be proven wrong - that the oil pressure problem would still exist - so then I've got a bunch of money into a pointless rebuild. Besides, as discussed previously in this thread, I am a guy with zero previous experience in this so my belief all along was that I would probably fork this whole thing up so bad that it wouldn't ever run again anyway! Then I would be right back to where I was when I decided to start tearing into this thing in the first place, which was that f my cheapest option was to source a different used motor than what did I have to lose by playing with this one? It was this realization that sealed the deal on putting it back together with as little further expense as possible! Besides, if I got lucky and it ran but still had low oil pressure or some other issue I figured I could always take it apart and do it again but the next time with all the right parts and with experience! So in early December I finally order about $500 in parts. I bought the two new paddles and the AOS that was broken, as well as every seal, o'ring and gasket I could find on the engine diagram. (Turns out I missed a few!) I then took the rest of December and all of January to very slowly and meticulously clean everything and put everything back together, following my notes and photos, Bentley, and these forums. As stated earlier, patience prevailed! If I was in doubt about how to do something I would find a few more videos and take a few more hours or even days to complete that task. Certain things -like those pesky 4-6 piston circlips, created quite a bit of stress and had to be done and re-done several times before I was confident I had done the process correctly. Then I would move onto the next step. One step at a time, that's all. Until all of a sudden one day it was back together! Since I hadn't been the one to pull the engine, it was also no easy task to get it back into the car but I figured that out too. Once the engine was back in and all hooked up, fluids in, etc., it was time for the start-up. I was so nervous I couldn't do it for several days! I was convinced it was going to blow up from a circlip mistake or one of a hundred other mistakes I had probably made. But finally in late February, and with my wife standing by my side to likely consul me, I turned the key. It fired right up and purred like a kitten! I let it run for a little while starring at my wife - BOTH of us in total disbelief of what we were hearing. I shut it down and we danced and cried. Literally. So now a month later I have driven it far further than I was able to when I first got it. What an amazing car. I can honestly say it has NO issues right now! NONE! The oil pressure is within proper standards at all times. It has no ticking sounds, Even cold starts are now clean. I've changed the oil already with zero debris found! Anyone who doesn't believe in miracles should because this is proof that they do occur! There was a million to one chance that this would be the outcome, given the problems encountered and my lack of any prior experience. But, for now at least, I have been granted a miracle and given another chance at being a happy Porsche owner! I don't want to wrap this up without expressing a sincere thanks to everyone who contributed to this and all the other threads on these Forums. Someone like me could never have accomplished something like this without this kind of info so readily available to us! By the way, it was these Forums, and the Bentley manual, that were my only co-pilots for this journey. I never had a single bit of physical help, nor did I end up buying Jake's video series. I even reinstalled the engine and trans all by myself!

Dude ! That is a top five post on here. I'm wicked happy for you, enjoyed the story and wish you a million happy 996 motoring miles. Thanks for the read and the inspiration !

Did you happen to appease Pele lately? Congrats on your completion of your project.

Awesome!

A ‘o ia! Drive on in good health!

Great read... Thanks for sharing and may you enjoy thousands more miles of carefree driving.

If I may ask, when you had your low oil pressure when the engine was hot, how did it manifest? Was it at idle that oil pressure was low?

Fantastic!!! Thanks for getting back to this thread. I totally get your feelings when you light it up for the first time. It's judgement time! I wonder how many engines you need to rebuild before the self doubt goes away? Awesome work! Now go drive that smile machine!

Great result and hats off to you for your perseverance and methodical way of working. And thank you for updating as your engine is proof that a non-matched combo of head, cam cover and cam bearing caps does not necessarily mean trouble. In that respect it might be worthwhile to change the thread title as you have proved it wrong? Anyway enjoy the drives in her you have well and truly deserved it!

What a fantastic ending, thank you for sharing. Happy motoring!

Good stuff, well done!

Wow, great job. These forums are a blessing for sure. Saved me more than once. In the end, you prevailed. Enjoy in good health!

Quotes source post: 17333143

Great suggestion! I'll change the title. And I appreciate the kind words too!

Quotes source post: 17332797

Yes, jim010, the oil pressure issue was most obvious at idle when hot. It would increase with revs but at hot idle it would always be below one bar, usually at .75 or below. I think the light came on at around .5 bars. Now it never drops below one bar, even when hot. I have come to learn that your oil pressure is also directly related to your water temp. So if you are overheating, or at the top end of the acceptable range, you could also experience these kind of pressure drops at idle. So be sure to check your cooling system to be sure everything is functioning to it's full potential. There is lot's of info available on this forum about cooling systems.

Quotes source post: 17333143

Lets see what those bearing caps looks like when turned over. That will tell you if there was a problem with them or not. Since they are aluminium, they can self clearance themselves but that doesn't mean the gap or the bearing finish is correct.

Quotes source post: 17334158

I have about a thousand photos but I just looked and I don't have any photos of the insides of those bearing caps. Too bad because it would have been interesting to have you look at and evaluate. Only time will tell how long my engine will be trouble free. But I'm going to enjoy driving the hell out of it while I can and if/when it does break I now have much more confidence that I could undertake a full rebuild.

Quotes source post: 17334146

Believe me, I have read alot of threads about this, but nothing ever satisfactory, and almost never does someone post what they did to solve it. My water temps are always in the normal range, but I continue to chase this along with a voltage drop when the car is hot.

Quotes source post: 17334202

I'm sure you will be fine just would have been interesting to see what the business end of the caps looked like. Fist time I had my heads off, I accidently put one of these caps upside down. Didn't realize this until I had to take the engine apart the second time (issue didn't related to the upside down cap) that this cap was installed wrong. The upside down cap created a lot of aluminium dust when I changed the oil the first time after the repair but there was nothing after it. The cap clearance itself however, the bearing surface of that cap was nowhere near what it was supposed to be. Second time around the cap was installed correctly but I'm sure now the clearance is more than ideal however, I'm not too worried about it.