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YOUR RESEARCHAsking for info
Leading reported evidence
Replace with uaos and track drain
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Leading evidence: 'Replace with uaos and track drain' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Repair /upgrades post purchase' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Performed · outcome unconfirmed
IIRR the shaft is used for 1 of the bearing races(or something like that).
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Suggestion
It's why other responses have said to budget $5k-$10K for repair/upgrades post purchase.
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Suggestion
You can tune them more aggressively, but you�ll have more �moving parts� to diagnose and repair when issues arise.
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Suggestion
To upgrade the IMS bearing and replace the RMS, you have to remove the transmission and while you have them apart you may as well replace the clutch and flywheel and it will be easier to replace the AOS at that time so you are looking at $3k-$4k in parts and something less than that in labour.
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Suggestion
To upgrade the IMS bearing and replace the RMS, you have to remove the transmission and while you have them apart you may as well replace the clutch and flywheel and it will be easier to replace the AOS at that time so you are looking at $3k-$4k in parts and something less than that in labour.
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Suggestion
To upgrade the IMS bearing and replace the RMS, you have to remove the transmission and while you have them apart you may as well replace the clutch and flywheel and it will be easier to replace the AOS at that time so you are looking at $3k-$4k in parts and something less than that in labour.
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Suggestion
To upgrade the IMS bearing and replace the RMS, you have to remove the transmission and while you have them apart you may as well replace the clutch and flywheel and it will be easier to replace the AOS at that time so you are looking at $3k-$4k in parts and something less than that in labour.
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Suggestion
And to put some real pain to the problem, the impeller blades are plastic composite so as too not damage the block when it lets go because it doesn't have a pump backing plate but uses the block as part of the pump cavity.
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18 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
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Not sure if this is the right forum or if I should be on the general forum but I have been looking at buying a 996 or a cayman(s) for a while now and I have done a lot of reading forum posts about the m96 engine and well its kind of confusing me.
So these engines have their issues and from what I have gathered these are the following:
IMS bearing (failure rate depending on if its a dual row, single row or a revised single row)
RMS leaks
Something with the piston rod?
Low oil during high lateral G's
Bore scoring(heard that it gets worse the bigger the engine is)
So I was wondering if I missed something or if I could get added info?
Because I do like balance from the cayman seeing as I came from an 944 cup. But the 996 seems easier to maintain and I also prefer the exterior but I do prefer the 987 interior.
Also if anyone can tell me what they would recommend or how their experience has been with their car I would definitely appreciate it.
Another issue..AOS failure which can lead to a destroyed engine due to hydrolock. Easily fixed by the UAOS (search the forum...)
I have a 2003 C2, love it. I have installed the IMS solution (first project upon getting it home), UAOS and replacement RMS (second project while trans was down for IMS) also the UIDS (oil control fix for high g oil control issues).
Be prepared for perhaps $5-10K in maintenance once you bring it home.
-Tom
Is this for a track car? Theoretically the MR layout is superior for handing than the RR.
I also think the Cayman will be easier to work on because you have direct access to the top of the engine.
Former Ducati jockey here. I love my '02 Cab. it's been bullet proofed. I wouldn't hesitate to drive it across country.
I look at the issues of the 996 differently. Because whole forests of trees have been cut down to make the paper to document the problems with the 996, it is in my opinion the ONLY used car you can buy today where nothing will go wrong with it that will come as a surprise. Think about it. Not a single thing can surprise you with this car because it's all been documented. There's nothing like it. It sold me on the car.
1) IMS Bearing, which will be done with a new clutch and flywheel
2) RMS replacement
3) AOS replaced with UAOS and track drain
4) Oil fill tube flex connector
5) Water pump
6) Coolant expansion tank
7) Coolant expansion tank cap
8) Aged cracked coils
9) Innumerable coolant hoses that age out
10) Aged out plastic parts
The problem you have is finding one that has been cared for well enough that all the known issues have been solved, or one that has been cared for well enough that it won't blow up before you fix all the known issues that have yet to be fixed. Unless you are willing to spend $50K for a completely sorted one, you need the latter and here is where that becomes a problem. The problem is that of all the generations of used 911s, the 996 was treated like the game of hot potato. You can find a good sample of gen 1, 2, 3, 4 911s that were loved so much by their owners that there are a good assortment of them with no more than three previous owners with an average ownership of 15-20 years each. This isn't the case with the 996. The number of 996s looking for its 5th, 6th, 7th, 8th, 9th and even 10th owners may be over 50%. For a 20+ year old car, that is a red flag.
I would look for one with plenty of service documentation and no more than two previous owners. It won't be easy, but worth the effort.
So what about the spun rod bearing. I also heard their was something with the connecting rod stretching and letting lose?
Also I saw a 996 a few days ago for 25k with an fully revised and rebuild motor and all the maintance documented. However it does have 233751 km on the dash. (engine was rebuild in 2019 with VIN muber WP0ZZZ99ZWS640799) It also has 8 previous owners.
Idk if I should buy it but it does also have the leather trim and the pccm+ installed and a few other options.
Okay so I did just find a Cayman S with the PDK and sport chrono from 2010 so the more sturdy engine but it does have 182000 km on the dash should I be worried about it?
To upgrade the IMS bearing and replace the RMS, you have to remove the transmission and while you have them apart you may as well replace the clutch and flywheel and it will be easier to replace the AOS at that time so you are looking at $3k-$4k in parts and something less than that in labour. It's why other responses have said to budget $5k-$10K for repair/upgrades post purchase.
Exactly. When I got my 996.2 home from the purchase (drove it home from Dallas TX to suburb of Atlanta GA) - that was my list. IMS solution, RMS, UAOS, flywheel, pinion shaft bearing, clutch and throw out bearing. So all of that was actually the "first project", but pretty much in that order. All with transmission down ONCE.
-Tom
I�m not too familiar with PDK, but from a brief observation of the different Cayman generations, the 987�s PDK is a bit primitive and problematic compared to the newer ones. I think you need to upgrade the cooling for it to reliably handle trackwork.
The new engine is great: it removes the IMS bearing, fixes some oil pressure issues and I think it doesn�t have a problematic AOS like the M96/M97. However, I think the possibility of bore-scoring is still present. I�ve also heard some whispers about piston cold-seizure in those engines too.
The MA1 engine uses direct fuel injection, which has its pros and cons. You can tune them more aggressively, but you�ll have more �moving parts� to diagnose and repair when issues arise. But you�ll also need to be picky about your motor oil selection to ensure that it works well in your application.
The 987.2 also allows for a straightforward motor swap, upgrading to a 997.2 Carrera S� motor, if you start getting hungry for more horsepower.
Regardless whether you opt for a 996 or a 987, a pre-purchase inspection is highly recommended. I wouldn�t avoid a high-mileage vehicle if it has been serviced well throughout its lifetime. With all cars, you�re �buying the seller� as much as you�re buying the car.
You don�t really have to worry about connecting rods with this engine. Spun bearings, yes, but that�s mostly if you have oil starvation, most typically due to track driving with stock oil systems (high G turns). If you want to avoid that, UAOS and UIDS will mitigate against that, along with a close monitor of engine temps and use a 5w-50 engine oil.
The biggest issue with the 996 and even other models (997, Cayenne, others), is bore scoring. Use top tier gas, change the oil frequently, avoid short trips, drive the car regularly).
The IMSB is also an issue, but frankly, changing that out does mitigate that as well.
Water pumps fail on these cars, so most change them every 4-7 years. You don�t want a cracked heat if the water pump fails.
A water pump failure in a regular car doesn't have to be a big deal, but in this engine, it can be which is why we replace it every 5+- years. The vanes of the pump that move the water are made or either metal or composite material. You can specify which when you buy one. If the vanes break off, they can get stuck in the narrow passages inside the engine and create a hot spot which leads to engine failure. The metal impeller vanes pose an additional risk in that the tolerances inside the pump housing are very tight and if the pump bearing fails, the metal vanes could touch the inside of the housing and damage the engine block. We all generally agree that replacing this with the composite impeller blades is a good idea, if you don't know what the pump blades are made of, and you don't know when it was last replaced.
Problem with the m96 water pumps is their bearing design is not the usual with 2 hardened races. IIRR the shaft is used for 1 of the bearing races(or something like that). This causes very fast bearing failure from start to finish.
M96 is Unlike other cars that show signs way before a catastrophic total failure. And worse case scenario is a overheated engine, but...you get a warning with most other cars. You get that sweet hint of hot coolant smell when car is hot. Maybe get a drip from the weep hole for weeks or longer. All events that happen to 'normal car water pumps, maybe for weeks/months before total failure. Unfortunately these events
can/might
happen in 1 ride on a m96. you can leave with a seemingly fine water pump, go a hundred miles and have a failure with no warnings.
And to put some real pain to the problem, the impeller blades are plastic composite so as too not damage the block when it lets go because it doesn't have a pump backing plate but uses the block as part of the pump cavity.
So,,, too really insult all m96 owners, these impeller blades break off and clog up the heads coolant passage ways causing hot spots that cause the head to crack and cause oil/coolant intermix...
Heed the advice of others here on changing out the WP regularly to avoid possible BIG problems. This isn't your mom's BMW....
jmnsho
This is the broken impeller that came out of my 996.2. Went from being tight and quite, to leaking badly and sounding like a bag of rocks in a matter of 1 day, maybe less than 50 miles. . Was on my list of maintenance to do list, just didn't get to it soon enough...
Back flushed cooling system numerous times in numerous ways and never did get out the broken impeller pieces....
