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YOUR RESEARCH2 C4 IMS bearing
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Install ims solution
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The worse we've seen in the last month was a shop that still installed an IMS Solution after they scoped the bores and found two scored cylinders rather than doing what is right and telling the customer they can't do the install.
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Ask most any mechanic that has replaced an IMS bearing and they will confirm this.
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Only, during this fiasco, we discovered that the engine was replaced.
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Full disclosure: I'm running an open bearing (no seals on either side) in my 997.
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The factory replacements used after 05 (I think) used the 997 bearing, I have one and it's highly recommended to pull the outer grease seal.
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Suggestion
I see only one reason you would like to remove the seals and that is if the bearing already have started to fail and is filling up the lubrication with debris, then you would need to flush(clean) the inside to slow the wear.
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I asked because i thought there was a pre-qualification of some type before installing the Solution and i assumed that would involve inspecting the existing bearing.
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The worse we've seen in the last month was a shop that still installed an IMS Solution after they scoped the bores and found two scored cylinders rather than doing what is right and telling the customer they can't do the install.
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Suggestion
The seals have one job to keep the grease inside , so once the grease has gone the seal has no purpose but , everyone makes their own decisions on their own car and this is just my opinion but backed up by a lot of other knowledgeable people , I have read on this forum recommending the same .
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But, look at pictures of failed bearings, they are still not overheated.
Hello,
Had asked a garage to have the IMS bearing upgraded to an oil-fed one. They say that the factory bearing is bigger than the tunnel, and the pull tool is not able to drag it out. Apparently, the best option is to have the engine out. Which, I'm opposed to. Here's a pic. This engine has a bigger bearing (~62mm), are there special tools need to replace the IMS?
If there is no apparent problem with the bearing just put everything back and keep it. As long as you don't mistreat the engine it will not fail.
EDIT: The case needs to be split to get that one out.
Removing the seal is controversial. I would not do it because it opens the bearing to debris, search this forum and check what people find in their oil filters. That can also get in the bearing if you remove the seal. If it turns smooth, I would do nothing, just put it back.
Fair enough. I look at the sources and it seems the folks I trust are recommending removal. Also, the vast majority of the replacement bearings are open. Change your oil on schedule and you should be good.
Full disclosure: I'm running an open bearing (no seals on either side) in my 997.
I'm surprised the shop you are dealing with doesn't know about the non-serviceable larger IMS bearing. In order to replace those you have to disassemble the entire engine and split the engine cases. Also, the larger bearing will last the life of the car with proper oil/filter changes. This whole scenario does not speak well for the shop you are dealing with. In other words, they should already know this.
I hope I'm reading it wrong, but if they used a puller on the bearing in the process of discovering it won't come out, I'd be very concerned about damage to the bearing.
Two curious questions come to mind.
What model and engine is this? (No 996 had this bearing originally)
And, what made you think you need to have an oil-fed IMSB? Any signs of IMSB going bad?
The factory replacements used after 05 (I think) used the 997 bearing, I have one and it's highly recommended to pull the outer grease seal. When I pulled mine the grease seal looked perfect but oil flowed out (not much) when removed.
The oil fed IMS Solution is the best replacement available and has been proven over and over with not one known failure.
It is a '02 996. Only, during this fiasco, we discovered that the engine was replaced. I was relaying on the VIN, and the history received from the previous owner didn't mention that. And, he's is not aware of an engine swap either. Called a couple of dealers, couldn't get much out of them either.
Your mechanic might have business insurance to cover repair costs caused by his negligence. Worth asking. You might also ask your own insurance company if this type of 3rd party damage might somehow be covered. Worth a phone call.
If this is an 02, a simple check of the engine number would have shown AT within the number. At that point, the mechanic should have known this was a possibility. Whatever you do, do mot take this car back if they tell you it is all okay without splitting the engine.
I was rather miffed when that was suggested as an option. Quite glad that I'd asked for a couple of days to mull over this. Perhaps, seems like that's the route.
I think some in this thread might be a little hard on the mechanic. Just because some of us are interested enough in one specific car model and engine doesn't mean every german auto mechanic, who often needs to know a lot about several models and engines, should know.
A 996 with a newer replacement engine is still pretty rare. The 996 is definitely an outlier when it comes to its numerous defects and quirky facts about them.
Anyway, seems like an honest mistake. I''m fully aware of how difficult the auto repair business is. I'm just hoping they have insurance to compensate you!
No need to be hysterical and demand a rebuild. If the bearing checks out ok just push it back in and ask for 10k miles full engine insurance. After 10k miles do an inspection of the bearing and if it doesn't turn butter smooth any more, ask them to fix up their mess. Oil in the bearing is no problem, 5w40 works fine for lubrication. These bearings are not too weak, they died because of other things...mainly debris in the oil and running the engine too hot.
And I second what others have said about that EPS tool, NO WAY.
Oil in the bearing is no problem as long as it is allowed to flow in and out so that fresh, cooler oil gets in. A failing seal that allows very little transfer is a problem.
The friction losses from this bearing is less than 10w(worst case) with correct lubrication (5w40 engine oil or correct grease). It's pressed in to the IMS (which acts like a big heat sink) and it's externally sprayed with oil during operation. 'Yes' it will heat up inside. 'No' not to any significant degree. You can logically understand this by thinking about your wheel bearings. They take at least 10x the load and they hardly heat up when cooled by air.
I wouldn’t worry about the case notch.
If I were installing The IMS Solution, I’d probably notch before removing the IMSB just to make sure no debris gets inside.
The “compromised case” is not an issue.
If you installed The IMS Solution, you’d have a notch anyways.
The bearing now needs to be replaced.
That means the engine needs to come apart.
I suggest installing The IMS Solution.
Thanks for posting!
I’ve been considering advertising locally that I would install The IMS Solution.
Checking the engine number will be one of the first tasks, before any invasive qualification work!!
Yes I would remove the seal, what happens always is that oil gets inside the seal, this happens every time, so if you think you have a bearing with the seals still in place that may still be nicely packed with grease, your wrong!! The bearing will have oil inside and the ims shaft will be full of oil aswel! Now with the seal in place all it does is severely restrict the flow of oil into the bearing , so the small amount of oil inside the bearing slowly turns acidic and attacks the ***** of the bearing causing pitting in them so they don't run true in their bearing race, this is how failure starts and just gets worse! So if you have the car at this stage please remove the seal, then change your oil every 6 months or 5k miles and you will be all good. Once you have stripped one of these engines and removed and inspected the IMS , removed the seals , pulled the bearing seen the oil run out of the shaft you wouldn't doubt this!
Noz1974:
I don't doubt your observations and I totally agree with you on frequent oil changes, for IMSB and other reasons.
For the IMS to fill up with oil it needs to pass thru the bearing(and both seals). This means oil can move between the IMS and rest of the engine, the bearing does not act like a check valve. Maybe not fast but there is still movement of oil.
Oil does not turn acid inside a bearing, it's mainly the blowby from the combustion which causes acid levels to rise in engine oil. So, if non-acid oil gets inside the bearing it will not turn acid inside there(you know this logically from gear box oil). IF acid oil gets inside and cause corrosion, you will see other traces inside the engine other than just a mangled bearing. The surface of other metals parts would show signs of corrosion also. From the pictures I've seen(please post link/picture if you have seen corrosion), the bearings looks to be free from corrosion.
I see only one reason you would like to remove the seals and that is if the bearing already have started to fail and is filling up the lubrication with debris, then you would need to flush(clean) the inside to slow the wear. But, in that case you would feel it when turning it by hand, it would not turn smooth anymore and you would change it instead.
Nick
Have you stripped one of these engines down ever? I promise you in most occasions on removal of the IMS, the shaft behind is full of oil honestly, my point was that don't think your running an ims bearing with the factory grease still inside , not at the mileages we not have with most 996. I think that having a bearing with lots of oil flowing through it to keep it cool and lubricate it is better than a bearing with restricted lubrication due to the seals being in place . The seals have one job to keep the grease inside , so once the grease has gone the seal has no purpose but , everyone makes their own decisions on their own car and this is just my opinion but backed up by a lot of other knowledgeable people , I have read on this forum recommending the same .
I fully believe you(I have no reason not to) when you say that there is oil in the IMS and it's bearing. I'm sorry if my english is not good enough to reflect that.
The problem is that the heavier grease is displaced by lighter viscosity oil that does not circulate freely in and out of the bearing; it can only seep through the seal. The shaft itself is basically a light gauge hollow tube, and I doubt it can absorb much heat from the bearing. You really need the sealed-in grease or circulating oil; semi-sealed oil is not adequate.
Wheel bearings heat up, but the knuckle they live in is heavy cast steel that is a far better heat sync than the IMS. Also, wheel bearing do not turn the kinds of RPM that the IMSB sees.
I've read through the multitude of replies and I must add that the shop already compromised the original bearing by pulling on the center race which loads up the ***** to the outer race. To top that off, pushing on the center race will just make this worse. The forces applied to the baring cause b
rinelling which results in permanent indentations in the races caused by the forced transferred through the *****. Shop messed up royally. Engine disassembly is the only correct course of action.
Maybe my wheel bearing example was not that good. How about
: I'm wiriting this on a macbook pro and it's generating roughly the same heat as the IMS bearing does. We are talking very small amounts of heat, it's a ball bearing, it's supposed to generate minimal friction forces.
If we take my laptop, strap the IMS shaft to the CPU as heat sink and then submerge it all into an oil bath. Then it would be rather overkill cooling. Same as the IMS bearing.
If the bearing is in a mode of failing, then yes, the heat goes up drastically. But, look at pictures of failed bearings, they are still not overheated.
This is a disaster. Shop is responsible. Have them drop the engine and put it on a pallet. Ship it to Flat Six for a rebuild. Take out a second mortgage on your house, you will need it, unless you have a spare 15-20K in your bank account. There really is no other remedy since they attempted to extract the bearing which cannot be extracted. Boy what a screw up! If it were me, I would already have the car out of that shop and would have it shipped directly to Flat Six. Please listen to the experts:
I've read through the multitude of replies and I must add that the shop already compromised the original bearing by pulling on the center race which loads up the ***** to the outer race. To top that off, pushing on the center race will just make this worse. The forces applied to the baring cause b
rinelling which results in permanent indentations in the races caused by the forced transferred through the *****. Shop messed up royally. Engine disassembly is the only correct course of action.
__________________
Charles Navarro
President, LN Engineering and Bilt Racing Service
http://www.LNengineering.com
Home of Nickies Cylinders, IMS Retrofit, and IMS Solution
^^^ Had they known anything about the different bearings they would have known before they even took the flange off... The big bearing has THE BIG NUT!
This from someone that knows what they are talking about. Your motor needs to be torn down and rebuilt!
You had a perfectly fine motor and your mechanic ruined it...So sorry you have to go through this.
An extreme example of a trunk job would be a car that comes into the shop in pieces, with the engine already disassembled in boxes on a pallet, but sometimes in the trunk or in the interior, hence where the name came from. Not something I coined :-)
Comment on the bearing seal. My car also has an 05 replacement engine with the large bearing, discovered the large bearing while replacing the clutch and RMS.
Following the recommendations here, I removed the real seal of the bearing. The way I did this was by very carefully inserting a dentist pick and pulling on the seal. When it came off it sounded like when you open a soda can, so it had pressure, either high or low but its internal pressure was different from the outside. The inside of the bearing was very dry, it had no oil and no grease whatsoever. Engine had around 45k miles at the time.
I worked for a shop back in the 90s that took in a couple of trunk jobs.
They never were warrantied, and they never turned out well.
Literally the parts were unmarked in boxes.
The customers had torn down the engines themselves and dumped the parts in boxes.
These were the same people who didn’t want to buy any new parts.
I would NEVER take on a trunk job.
This one at least is not disassembled yet!
I dont really understand the pitfalls of rebuilding this motor. I get they damaged the bearing but thats it. U could check the flange area for stress cracks if u were worried that they pulled against the case. Otherwise the motor is intact. What am i missing? I get Jakes screening process and how pickey he is but for the rest of the crowd its seems low risk.
also not sure what the shops insurance would cover. My bet would be the r and r for the bearing which would include a tear down to swap the bearing but not a rebuild that most if us would feel is correct. Hell i bet it would be cheaoer the get a porsche short block and swap over the rest.
That's interesting. If it was 100% free from lubrication it's a manufacturing issue. You never seal a bearing without putting some lubrication in it...never. The normal fill is 15% of the void space, which would look like 'very little'. When the bearing is run it will press away some of the 15% so after some time it will be even less, but they don't need much.
Charles, will brinelling occure 100% of the time when you pull one of these bearings?
This is normal. Bearing will have no lube in it but if you pull the bearing, there will be a substantial amount of very dirty oil behind the bearing. Ask most any mechanic that has replaced an IMS bearing and they will confirm this. The grease seal lip gets hard and stops sealing, allowing the engine oil to wash the grease out. At that point, the seal impedes lubricant flow in and out of the bearing.
[QUOTE}Charles, will brinelling occure 100% of the time when you pull one of these bearings?[/QUOTE]
Once you load the inner race to pull the bearings, the force transferred through the ***** to the outer race can dent the races and *****. That's why it's standard operating practice to replace any bearing that has been pulled in this way. This isn't something I came up with on my own.
Of course. I have probably heard this term before. Never thought much about it.
I guess this is more of a frunk job. Still doesn't change my theory on Jake's vetting process. He checks the owner first...
WHEW! Good thing I got in before he starting the vetting process. I would have made it past a close intense scrutiny!
...but I totally understand why it is becoming necessary these days.
Couple of newb questions. So we confirmed that he has the larger non serviceable bearing. What makes it non serviceable? I�ve never seen one up close. But the way it works from what I understand for a normal bearing is that the tools attaches to the stud coming through the inner race. You remove the clip holding the outer race/entire bearing and pull it out. Why would that not work for the larger bearing? It looks like from the larger IMS bearing pic above you can remove the clip and just pull the bearing out? I was under the impression that the hole in the case the IMS comes through is not big enough for the bearing to move out. But then how was he able to pull it out 3-4mm?
Anyone watch Home Built By Jeff? He tried to pull his IMS bearing out with a home made tool. Banged on it for a while and no luck. So he just put it back together and is still driving the car.
and is that sealant in the original pic between the case halves normal?
I'm speculating here but would it be possible to pull the seal and do some sort of visual inspection, it may be the mechanic started the process and realised what was happening before he got any serious load on there , if you could sneak a look at the outer bearing race it may indicate whether it's damaged or not. I presume you would see the indentation in the bearing race with a scope or something similar, also turning the bearing and feeling for any notchiness in the feel maybe ?
You might be able to spot a bad bearing, but you won't be able to confirm that it is OK.
These dents (if there) are probably visibly insignificant...like you might be able to see them if you removed the ***** and examined them under a magnifying glass. And you'll need the feel of a safe cracker to detect anything more than blatantly obvious roughness just by turning the bearing.
Bearings like this have very precise tolerances and turn at very high speed. There really is not way to confirm that damage has not been done.
I didn't mean to imply that this was just about heat. It's a factor, especially when the bearing starts to fail and runs a bit hotter.
It's probably more so about inadequate lubrication.
OK Still trying to work this out. If he put the puller on the stud and the tube catcher thing through the hole that is smaller than the bearing it would be resting on the bearing, then how did he get the bearing to move? Doesn�t pulling on the stud bring the bearing into the tube catcher thing? If the bearing is bigger than the puller it won�t fit.
If I understand how a bearing puller works. Which I think I do since I have used a bunch of them in the past.
If he used a TON of force he could have pulled I guess the inner race in and destroyed the bearing. But the pic looks like the bearing is intact.
Does this make sense to anyone else or am I way off?
Or maybe he tried to pull it with a slide hammer and not the tool.
There is room between the shaft and included bearing and the case (block). Attempting to pull the bearing from the shaft would then place the bearing against the case. The act of pulling the bearing via the stud, the stud which only contacts the bearing on the inner race, will destroy the bearing. So now you have a bearing, not seated fully in the IMShaft, that if pushed back into the shaft is now damaged.
The only way to now correct is to disassemble the case/block/engine to get to the IMS.
-Tom
It doesn't really matter. One advantage is that any debris created won't (shouldn't) contaminate the area of the IMS/ IMSB. On the other hand - if you can't get the bearing out, you've just wasted that time/ effort.
I asked because i thought there was a pre-qualification of some type before installing the Solution and i assumed that would involve inspecting the existing bearing.
Point blank.A mechanic/technician that is well versed in 996 ims bearings would know that large center nut means bearing cannot be changed unless engine is removed from said vehicle and disassembled.Matvrix I am sorry you are going through this unfortunate situation.
That is correct - IF you want the replacement IMS (bearing or solution) to be warranted. You must follow the pre-qual.
If all you want to do is get the car back on the road - skip the pre-qual. (in general - not in the case of this owner/engine...)
-Tom
Sorry chaps, well and truly relied on this garage to carry the torch. Especially, when they were ref here on this forum. After all, the lead is an ex-Porche mechanic and all that. Quite, going to bite my tongue and have them disassemble it without invoicing me an arm and a leg. Right, really invaluable, you are!
Dg
Normally when removing an ims you slot the cylindrical tool through the hole in the case which it's designed to fit, the outer edge of the cylindrical puller sits on the outer edge of the shaft with the inner diameter of the puller big enough to accept the bearing as the pulling part of the tool in the centre attaches to the ims stud and pulls back , all good but.....
Problem with larger bearing is the end of the ims shaft is bigger and the bearing is bigger , the bearing is so big it won't even fit through the ims flange hole in the crankcase , so when you put the tool on its resting on the bearing not the outer lip of the ims , then the stud puller in the middle pulls but the bearing has no where to go as it's trapped by the cylindrical part of the tool but even if you could pull it , you would have to pull it through the crankcase which you can't coz it's too big. This garage has started the procedure but put load on the ims stud to start the pulling process, normally not a problem as once the bearing is out , it's not re used but now they realised they can't get it out but have compromised the bearing by using the puller which could have damaged it inside as it's not designed to take a sideways load of such force, shame as the larger ims has the lowest failure and with the seal removed is usually ok to leave alone , I think the op thought he must have had a gen 2 small single row bearing but must have got the gen 3 large single row bearing without realising !
I'm sorry, but there is no excuse for what the shop did. There is no way to confuse the 06-08 bearing with the earlier one. I don't care what credentials they have from Porsche. They lack situational awareness.
I hate to be the one that has to pop this bubble, but there are lots of shops out there that aren't qualified to work on a lawnmower. Some days we are all completely exhausted with calls from people lacking the wherewithal to work on any car. That is the reason we have pre-qualification and registration requirements. You can't trust that a shop is going to do right by you blindly. Shops are beating themselves over the head for these jobs and consumers are shopping by price, not value. We've seen jobs where they don't even change the oil and filter when changing out the IMS bearing, just for make up oil to top off what is lost when the flange is pulled. The worse we've seen in the last month was a shop that still installed an IMS Solution after they scoped the bores and found two scored cylinders rather than doing what is right and telling the customer they can't do the install.
Where we don't require a Preferred or Certified Installer to do the install, the pre-qualification and registration are required. This page goes over what should be done prior and during an install for those unfamiliar with the process:
https://lnengineering.com/products/i...ification.html
