996 C2 3.6 53 plate

[Sump]

I'm eying up a Porsche but just can't figure out the IMS / Bore issue sitation with this particulaor engine.

Now my research has gathered the following:

IMS - Single Row , should still be replaced for safety. That's fine with me.

Bore scoring issue doesn't effect this car and is with the earlier 3.4s etc?

The car in question is a Porsche + 1 owner car who has had it for 9 years and covered 65k.

I have looked up the issues like radiations, expansion tanks etc. I am ok with all of that as I have my own 2 post ramp and Im handy with a spanner.

What I need confirming the bore and ims side of things. RMS should as I figure be ok on this car aswell?

Also when looking at one in person, other than the very obvious things, what should I be listening for in particular and looking for extra carefully that is very 3.6 engine specific?

[mollytherocker]

Pretty much all you need to know is on Hartechs website.

[Sump]

My problem with the Hartech bit was that they said not to worry about the IMS bearing yet they rebuild engines. Isn't that a conflict of interest?

[cd1957]

Hi the 3.6 does have bore scoring issues,the ratio of IMS failures is small compared to number of cars sold,and even modified crankseal can still leak,if the crankshaft/crankcase alignment is out,which is also part of the issue.

Chris

[Stokepotter]

I have the very car you are enquiring about all be it a 2002 model with 80K on the clock.
It has full service history and I note from the service invoices that it has already had the RMS replaced due to a "severe leak" back in 2008.
Following a visit to my OPC on Saturday for the complimentary health check a leaking IMS seal was reported. I was informed that it would be sensible to have the clutch replaced at the same time as the seal.
I have made a few enquiries and Sport & Classic in Knutsford will do the clutch, IMS seal & RMS for £900 including VAT. If I want the IMS bearing replaced as well with one of their upgraded bearings the price goes up to a eye watering £1800.
Although this seems a lot, apparently, the price to upgrade the bearing alone is £1300 so with having it all done at the same time it can be a lot more cost effective.
I have decided to go the whole hog and have the lot done regardless of whether it needs it or not.
The whole should I/shouldn't will it/wont it issue will then go away and I can do what the car says on the tin - namely - Enjoy It!

[Sump]

I'm thinking about just dropping the engine and transmission when I get it and replacing the IMS bearing with a new pelican one. Can buy the tool and sell it on ebay when done.

[911p]

I thought the Mk1 was mainly affected by IMS failure, and the Mk2 mainly by bore scoring?

[thegoose]

The IMS is a potential time-bomb - it may never go off and you'll be unlikely to get any notice if it does. Mine (3.4) was caught luckily as it happened to be on a ramp and was spotted as noisy, so it was replaced preventatively and has been fine ever since (2 years, over 15,000 miles).

So, whilst very few fail it might be worth considering changing it so you avoid the gamble - it's always hard weighing up the risk and what's at stake, in this case the risk's very low but the stakes are quite high - up to you which way you go with it, either accept the risk yourself (as I probably would) of a bill for a few grand IF it fails in the future but free if it doesn't compared to definitely spending £1000++ now to virtually guarantee that it won't (for 50,000 miles at least, such is the stated life of the replacement bearing).



However, before buying the car you should get the bores inspected by someone that knows what they're doing to see if there's any evidence of scoring - the low average mileage that car's done may make it more likely to have an issue but it's hard to generalise. If scoring has started then a rebuild WILL be required at some point in the future, so should factor into your purchasing decision.

[Hilux2400]

This is the same year as my car, also a C2 3.6, and with the original engine the number would probably be in the range M96/03 663 2****. The "3" in the 663 denotes the year.

I discovered in my car that the engine number is M96/03 AT 665 66***.
46,630 units later than original.

The "5" in the "665" group denotes an engine from 2005 and the "AT" denotes "Austauschmotor" which means exchange. For some reason my car had an exchange engine in late 2005, which I assume was done under warranty.

Check the engine number to see if it has "AT" in the group. As you look at the car from the back the number is underneath on the passenger side on a slight flat upstand near the joint between the block and sump plate. I think that some of the later M96 engines had a different IMS bearing, but I am not sure on the numbering, but later is better I have been told.

[911p]

Hilux2400 said:

The "5" in the "665" group denotes an engine from 2005 and the "AT" denotes "Austauschmotor" which means exchange. For some reason my car had an exchange engine in late 2005, which I assume was done under warranty.

Doesn't necessarily mean it was exchanged in 2005. Our 996 C2 had a 2005 exchange engine but it was installed in 2008; just means an '05 block has been re-used.

[Hilux2400]

911p said:

Hilux2400 said:

The "5" in the "665" group denotes an engine from 2005 and the "AT" denotes "Austauschmotor" which means exchange. For some reason my car had an exchange engine in late 2005, which I assume was done under warranty.

Doesn't necessarily mean it was exchanged in 2005. Our 996 C2 had a 2005 exchange engine but it was installed in 2008; just means an '05 block has been re-used.

I follow your reasoning on dates. Does your 2005 engine, installed in 2008, have an "AT" incorporated in the engine number? I think I have picked up from somewhere that "AT" engines came complete with heads, manifolds and alternator. was your engine like that or just a block? Also where was it in the 500 to 65000 numbering sequence? I have been trying to get more info on this and every bit helps.