help!! coolant in oil and smoke

hello all i have a 1999 996 with 78k mi. i found coolant in the engine mixed with the oil and the car is smoking like crazy. it is only smoking bad out of one tail pipe. the car starts and idles, is there any wany to find out if its the head gasket opposed to a cracked cylinder. would an oil sepperator smoke out of one side? any help in diagnosing this or suggestions will go along way. thanks

AOS not smoke from one side... where are you located? I would advise AGAINST running the car untill a complete diagnosis can be made.

Quotes source post: 8341973

What he said.

Compression test it??

Or perhaps have a leak down test performed. Look for air bubbles in the water tank while doing the leak down test. I hope its something very simple.

I think the level of mix has to be determined - I cant see from here... there could be a simple explanation - or something more complicated. Has the car lost water, how long was it runm without knowing, how long with knowing...is the oil level UP, is the oil creamy or just the fill tube, how much smoke...I assume it from the passenger side? These cars are not as known for head gasket leaks as they are for other types of mixing... If I had to go out on a limb and diagnos it with this limited info I would bet on a cracked head - if you run it you can cause worse damage A compression check might not show the leak, a leak down of the coolant system should show there is a leak... in any event if the leak is internal the motor has to come out so the final diagnosis can be made once the head is off AFTER its determined there is an internal leak Do you have any sort of a warrany ?

Cracked head is my bet.. These failures are taking out more M96 engines than anything else and have been for over 18 months now. We are repairing 3 of them at the present. It could also be a cracked cylinder, the symptoms are very similar. 99 engines are plagued by cylinder issues. It is NOT a blown head gasket, the heads crack on these engines before the multi-layer steel gaskets fail. WE HAVE NEVER SEEN a head gasket fail, not even on an engine that saw 300F coolant temps. It is also more than likely not the oil/coolant heat exchanger, we've only seen one actually be bad but most every car that comes to us with intermix has had money wasted changing this hoping it was the source. Be especially careful with this, collateral damage from this can render the engine non-repairable. We save about 60% of the engines we see with this form of failure, the other 40% are toast. Do you have coolant and oil mixed both ways?? The repair for this can be complicated and it might be capable of being saved, or it could be toast... A very detailed evaluation is in order. I diagnosed the last one in ten minutes.. Pulled the head and found the crack immediately, it was welded today and will be finished tomorrow and the engine goes back together Wednesday.

+1, cracked head.... opposite side of where the smoke is coming from, start there. Hopefully Doug (dharn) will chime in and can shed some light.

What would I know about cracked heads? In all seriousness, don't give up or just buy a new engine, often times this can actually be a reasonably easy fix. And I am happy to see that Jake Raby is now actively fixing engines with cracked heads, he is probably the most knowledgeable pro around on these engines. When I found out that I had a cracked head 2+ years ago Jake was not fixing the cracks, now he is and that is a great thing. Not driving the car until it is fixed is great advice. The less you drive it with contaminated oil the better it is for the car. That being said I can tell you that by the time I found out I had intermix my oil was severely contaminated, the look an consistency of a chocolate milkshake, and the coolant was the look and consistency of vanilla pudding. I had the head fixed and spent many hours flushing the cooling system, which may be the most difficult part of the fix. No new bearings or rebuild. I now have over 10,000 since the fix and the car is running fine. The most common area for a crack is the inner exhaust valve seat of cylinder #1 (or #6 on the passenger side). Here are some picks of this crack from my car and another with the same crack. Believe it or not these are two different heads, from the look of the crack you would think they were the same head. You may be able to see the crack with the engine in the car by removing the coil and spark plug tube on the cylinder, but it can be hard to see. These cracks do not necessarily go all the way to the combustion chamber, mine did not and I never had any smoke. Are you going to try to do the fix yourself. I have loads of pics, diagrams for making tools, etc. etc. I will be happy to share all that I have.

alright lots of good advice! a cracked head sounds alot better than a cylider (fingers crossed). im located in cental pa. i dont have a warranty. i only ran the car to drive it on and off the trailer since this happend. there is oil and coolant in the motor but the coolant reservoir is to low to see if oil is mixed into the coolant and i didnt want to add more coolant or run it if at all posible. it is smoking from the passenger side pipe so then drivers side head/cylinder is the problem. i am planning on doing the work myself i have had success with several other builds and feel capable of doing this with the right info. so if you would be able to send me some info dharn i would greatly appreciate it. also i will likely need to get in touch with jake it seems to aquire a functoniong head, sould that be the case. thanks to everyone for the help with this

OK then.... you have a plan!! keep this thread alive, post pics and questions... we will all be hear to help and encourage you !

We have a very good repair regimen for these heads.. We can repair 3 of the 4 most common crack prone areas with absolute results. If the head is cracked in the 4th position, its scrapped and I can match another for you from our core bank and hot pressure test it. What the real concern is with a cracked head is collateral damage... Thats where it takes lots of experience with this is a real benefit.

PM me with an email address and I will start sending you info.

I will gladly document the process. this seems to be a more than rare occurance and if it will help others out i am glad to do it. i will hopefully have some time to work on it this weekend, so i will keep you guys posted

here is a link to great write up that i will be using to pull the engine http://www.oz951.com/public/enginedrop.htm

Now that is a great write-up. Makes some of mine look pretty shabby. The time it takes to do a write-up like that is quite extensive. Many times when I have started a project on my car I go in with the intention of taking lots of pictures, etc. but just get caught up in the process of doing the actual work and leave behind the documenting of the work.

oz951 website is gonna be an instant classic.... many people will benefit from his love for with the 996.

so i pulled the motor today. it went very well. compared to some of the other engines that i have pulled this one was pretty easy, a good write up helps alot. the next step is to disassemble the motor and diagnose the root of the problem. so getting a good look at the drivers side head is at the top of the list. i will be using a porsche 996 manual. the torque specs are also in here for reassembley. http://www.cannell.co.uk/Manuals.htm and a disassembley write up found here http://www.pelicanparts.com/techarti...erTech-162.htm

ok so ive been logging some crazy hours at work and havent had as much time to work on this as i would like. so this is pretty much done on weekend. Anyway. i pulled the head cover and i wasnt able to find a crack around the #1 spark plug hole. i didnt have time to remove the cam follower housing and the head yet but from what ive seen i should be able to see the crack if this were the problem. given the amount of smoke and oil in the coolant it seems that a cracked cylinder would be the likely cause but i remain carefully optimistic. so please inform on what you know about head crack palcement and if it could be somthing that could still be a factor and any info relating to cracked cylinders and where i would be able to locate a casting for a reasonable price. at this point im still hoping to rebuild the motor but only time will tell. i made the tool to hold the cams in place its not to pretty but its not $200 and works fine.

What is that yellow/greenish slim pouring out of the head? Is that the result of your oil/coolant mixture?

Just out of curiosity, why did we have him pull the driver's side when it was the passenger's side that was smoking?

bank one exhaust goes to the passenger side and bank two, to the driver's side. the lines cross at the cats to different sides.

I would go ahead and take off the the tappet base and see if the crack is visible. It usually starts at the valve spring seat and then travels to the tube so it is possible that it has not gotten that far. And you will have to do this to get the head off in any case. If there is no crack visible at the spot I showed Jake has said that there are 4 areas for common cracks. Maybe he could tell you where else to look. And with the head off you will be able to see if the cylinder is cracked. I know of one case where the leak was from a casting flaw in the head that resulted in a pinhole leak developing. The leak was only found with pressure testing, but was fixed. I would also suggest that you get an engine stand so you can rotate the engine, I think that I paid all of $75 at PepBoys for mine. Then take off the other cam cover and the sump, oil cooler, water pump, etc. You want to let as much of the intermix drain out as possible. Cleaning the cooling system is a big pain too.

Joe, Thank You.

r1de23..yes that is coolant in the oil. doug good info as always. i should be able to pull the head off sat. to hopefully get a clearer diagnosis. i have an engine stand that i will be using i got a little ahead of myself trying to find a crack. if you know of a writeup on cleaning the cooling system that would be very useful.

No write up but I can tell you what I did. Had the engine out with the cam covers off, one head off, pan off, water pump off, oil cooler, oil pump, etc. etc. etc. Let it drain for several days while rotating the engine so most everything dripped out of the engine, and spent some time further cleaning the junk out of spots on the engine. As for the cooling system, took all hoses off from front to back. The emulsified coolant is hare to get out of them, it just sticks to them. Took the radiators off and took them to a shop for hot flushing. ran rags through the cooling tubes that run from the front to the rear of the car, remember that there are hoses at the mid point that need to be removed. This helps with access for the rags. I used an electrical pull tape to draw rags through the pipe. With this I probably got 90%+ of the crap out of the system. This did not include the heater coil in the dash. When the engine was back in I used a diluted coolant and flushed it out and changed it several time. By the way I use Peak 50/50 with no problems, The system hold about 6 gallons of coolant so if you are going to flush it and replace it a few times and you want to use the OEM coolant get ready to spend hundreds of dollars on coolant that is going to be disposed of (at the local Jiffy Lube for me). You could use distilled water for flushing, but I would not run the car for long on straight water. For the engine oil I used a similar approach, filled it with some non-synthetic oil, ran it for a few miles, drained it and replaced it a couple of times, then went to synthetic. This held down the cost of the multiple flushes of oil. I don't think running a good non-synthetic for a few miles is a problem. I am sure if I had my coolant tested there would still be traces of oil in it. The pudding that the coolant becomes is really hard to get out, and the heater core is pretty much impossible, although I guess you could flush it too. Having a bit of oil in the coolant won't kill an engine, not so good to have coolant in the oil. However, with all the oil changes I did I am not really worried about this. Be careful on the amount of RTV sealant you use on the cam covers and sump. You want it to seal well, but it doesn't take that much. By the way I used Permatex Copper rather than Drei Bond or Locktite 5900. If you look at the specs it is basically the same thing but actually rated for higher temps.

I have head castings.. No worries there. The cracks stem from 4 primary areas.. here are some examples. Over time we have developed a "fix" that can be applied to 3 of the 4 popular positions.. it takes excavating, pre-heating and post-cooling but it does work very well. The engine in one of my cars had two cracked heads, I used them after extensive repairs on purpose..

today i was able to get the head off. I found the problem and it is a crack on the bottom of cylinder #2. So not the diagnosis i was hopping for but now i know what needs fixed. if anyone knows where to locate an engine case let me know.

ouch...best of luck with the repair. You may be better off just getting a used complete engine

that looks familiar

well crud, that isnt going to be as easy. to fix...I feel for ya. there are case 1/2's available, Flat6 (jake) is your best resource and I think a long talk on the phone might serve you well. He will give you lots of options to think about. As stated, maybe another motor or depending on budget and time something more to your needs/wants sorry about your find....still hoping for a good outcome with a happy ending

Sorry to see that it is a cracked cylinder sleeve rather than the head, definitely more of a challenge. You seen to be going the direction of a new case, have you thought of having it re-sleeved by LN Engineering?

Kind of looks like the factory needs to learn about stress relief by slamming the metal hard then go for machining the head faces level.

I have plenty of engine cases.. Some with really good bores.. The really big issue is the risk that the piston rings will never seat upon reassembly amd its a big, scary risk that I refuse to take. These engines respond to re-ringing and etc much different than most. We've been bitten in the *** and know the limitations. Wait till you see the prices of replacement piston rings! You should explore all the possibilities, but what you found is definitely a perfect illustration of mode of failure #1.This was the first major failure mode the M96 engine family. We'll be happy tpo help you, I hate to see peopke waste their efforts just because they don't understand this engine.

so after some time i am getting ready to rebuild the motor. this is where im at now

are you re-using your pistons or rings? or going with new ones?

Wow, quite the project. Keep pics coming as you continue your work.GL

Quotes source post: 9209350

it will need new rings because the rings wear to the cylinder, i should be able to reuse the pistons. i have been looking into finding a short block so depending on what i can find i may go that route

New rings from Porsche are $1k Used short block or case $2-3k????? Total cost about $4k. Which is how much the LNE option is. We've been told re-using pistons is the "devils work". So why wouldn't you have your case reworked by LNE along with NEW rings, pistons, and Nikasil cylinders for the same amount???

I think you can get nice aftermarket forged pistons and rings for less than OEM...JE pistons sells a piston/ring kit for just over 1k for air-cooled 911's they might have some for water cooled ones if you contact them, I use their pistons and rings in my race bike

Quotes source post: 9215649

+1.. consider LN cylinder upgrade and you will get new forged pistons and rings included in their package. I'm awaiting my new 3.8 cylinders and many have taken this route. The only drawback is the turnaround time will be 4-8 weeks. Good luck with your rebuild.

JE certainly has a 3.4, 3.6, 3.8, etc application for the 996, since it is sold with LNE's Nikasil offering for about $1500 (included in the $4.1k case rework and new piston/ring offering). However if you decide to buy the pistons without the case rework it would be a custom "stand alone" order from JE, since by reading LNE's Nikies web page you find out ... "...that Boxster, Cayman, and 996/997 pistons are sold only with qualifying Nickies purchase..." And the other question is how well would it work and seal/meld with a used Lockasil case? From what has been said here before it prob. won't work well without the new cylinders to go with it. "I've never seen any good come from JE or any other piston inside a stock bore.. The last ones we saw failed horribly in less than 100 miles." ---Jake from: https://rennlist.com/forums/8899265-post53.html