motor part # location

[davea1954]

Where can the motor part number be found on a 2007 rebuilt 3.6 liter motor?
Also used 2002 911 I am looking at purchasing had rebuilt motor installed in Dec 2007 and since then has only been driven 12,000 miles, or 2000 miles per year on average. Is there a potentially greater chance of an IMS disaster because this low mileage/use on this rebuilt motor? Seem to remember an article 5 -6 years a go that said to be safer best to look for used Boxster/911 with at least 5000 - 6000 miles per year of use. Thanks.

[tonythetarga]

What you want is the engine model # and serial # not part number. It is located next to the engine oil sump as shown in the attached picture.
There is a difference between a rebuilt and a replacement engine from the factory. factory engines will have 'AT' as part of the engine number like the one pictured below.

The M96 is the engine type and the AT designates it as a factory replacement engine.
All factory issued 'AT' engines have a non-serviceable single row IMS bearing like the 997's from late 2005 to early 2009.

If it is a rebuilt motor, then you want to know if it has had an IMS upgrade to the LN Engineering bearing (ceramic single or double) or another type of bearing. LN issues a bar coded sticker with each bearing. Ask for work order records to see what you are buying. Post the engine number if you're not sure about what you have.

[davea1954]

Hi Tony, thanks for the info. The motor is a replacement from Porsche done under a CPO extended warranty, so now know it has beefier, yet non-serviceable IMS.

My second question is really the one I am more interested in having answered thought. Anyone have an opinion/thought on if the extremely low miles on this replacement motor (w/Porsche IMS Bearing, circa 2007), 12,000 miles, average 2000 miles per year, will increase chances of an IMS failure vs a car driven on average 5000 to 6000 miles per year at minimum, AND if there is an increase in this chance is it really significant? Thanks.

[tonythetarga]

It is hard to say since we don't know how it was driven for those miles. I think that with the fewer miles it should be OK as long as oil changes were done about once a year regardless of the low miles per year. If you buy it, consider the direct oil feed system for the non-serviceable bearing. It involves a new door to the IMS with an oil line and spray feature to the ball bearings. You do have to remove the outer seal of the bearing so oil gets in there. I'd negotiate in the 2k you'll need for parts and service (provided it doesn't need a clutch too). In any event, put in a new throw out bearing while you're there as they are plastic, inexpensive and do wear out before the clutch does.
Look at it this way, if the car only had 12,000 miles from new would you consider buying it? Probably yes, hell yes!
These bearings aren't that delicate, so with only 12k on it, it should be good as long as it hasn't sat in dirty oil with contaminants built up in it. 12K miles and no oil change for 6 years isn't good but if the changes were done frequently, then I wouldn't worry about it.

[davea1954]

Thanks again Tony, especially for your quick replies. It doesn't hurt either that I like your opinion!

[davea1954]

Hi Tony, just talked to current owner and he said car was driven about twice a week, more in the summer less in the winter, mostly trips around town but an occasional trip or two out of town too. Oil was changed once a year. So, at least the car didn't sit in the garage for weeks/months on end. Does this info add anything to the issue of the IMS reliability for this motor?

[tonythetarga]

If the price is right and the car otherwise looks good I wouldn't let the IMS worry me. I would however consider doing the oil feed conversion to put any concern to rest.

[davea1954]

Thanks Tony, looking more and more like there's going to be another Porsche in the garage.