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Posted by: Optimusglen Jul 17 2017, 07:23 AM

First, read this carefully. I'm not going to re-use the bearings. Never planned on it. I am just looking for input on condition and wear patterns.

This past weekend I was able to split the case on a 2.2T engine I am rebuilding for my 914. So far the tear down has been great, nothing broken, no chunks of metal or debris, everything came apart without much fuss, and the case has time-serts.

Case is apart now, most of the bearings looks really good, a few have some wear. I've had a few engines apart but not many, and those were special circumstances so I don't have a lot of personal experience reading wear on bearings.

One case half


From one end to the other, close up's on each of them


This one seems to have much more wear than all of the others for the crank.


The dark spot here is oil.




Wear on the far edge of this one.





For the intermediate shaft bearings:


More wear here too.



Any thoughts or input from you guys and gals? The engine was a core, unknown history. Buying it was a roll of the dice.

Posted by: flyer86d Jul 17 2017, 07:36 AM

That is about what my 914-6 engine looked like when I disassembled it. I guess the intermediate shaft bearing at the chain and gear end is subjected to a higher load than the pump end. Mine was worn to the copper as yours is and as evenly as yours too.

Charlie

Posted by: mb911 Jul 17 2017, 08:57 AM

I think you will be good to go with a measure and new bearings. My engine every single bearing was down to the "copper" and grooved so had to machine the case and the crank.. $$$$

Posted by: Optimusglen Jul 17 2017, 10:13 AM

Yes, I was firmly on the new bearings route, then someone on another forum mentioned that several have had issues with new bearings and quality control. That a lot of people have been getting their existing bearings coated (I assume like what Mark Henry does) instead. I understand that everything would need to be in spec for that to be viable though.

Hoping he can chime in, I'd love his recommendation.

Posted by: Luke M Jul 17 2017, 11:36 AM

I've had several 911 engines apart. from 2.0 to 3.2.. Some engines had bearings that looked like yours and some worse. You should be good to go with new bearings for most part. There was an issue with the bearings (mains and rods) being made in Brazil. If you can find the ones " made in Germany " you'll be better off. I searched for a while and found a dealer in the NE which provided me with the bearings for my brothers 3.0 .
I do not have the info handy but once I find it I can post it here or pm it to you.

The case through stud on the lay shaft should have a case saver installed if not already done. You will want to do that prior to having the case cleaned.

Posted by: gereed75 Jul 17 2017, 02:28 PM

i recently rebuilt the 2.4 T motor that was in my six. the old bearings looked pretty good, about like yours with the pump shaft showing the most wear. Sent the cases out for case savers and oil bypass mod. Thought I would take a chance and reassemble with new bearings. On final torque up of the halves, the crank would not turn. Back apart, off to Ollies who cleaned up the part line, re-sized the main bearing journals and reset the deck heights and provided barrel shims to set the deck back to factory zero.

Moral of the story - you are taking a chance on reassembly that the main journals are still round. They tend to ovalize in use. I had measured them before going to Ollies and they were about .004" - .006" out of round. Enough to bind the crank on re-assembly.

I also suggest that you have plenty of inserts handy (6 and 8mm) when you do the reassembly. The magnesium gets like dried cheese and if you are snugging up a case stud and it pulls and you have no way of fixing it the whole project goes on hold. Ones you think are good now may not be when you torque them on reassembly.

Look very critically at the studs on the tranny mount and the front engine mount. These pull too.

Not sure if that answered your question, just my experience after building several of these.

Posted by: Optimusglen Jul 17 2017, 06:28 PM

Lol, what? I was just looking for input on the bearings. It should be obvious that the case is getting inspected and line bored.

Inserts already installed all around including trans bolts, but this thread isn't about inserts.

Posted by: porschetub Jul 17 2017, 07:23 PM

There was bad batch's of rod bearings from Glyco for many years and from what I read they were rather poorly made.
Some of the key players in the engine business went to Clevite (Mahle) bearing for this reason,however many said the genuine Porsche (Glyco) were better than standard off the shelf ones....but more spendy for a reason perhaps ?.
Its seems folks check rod bearing install after being fitted to the rods,if the don't look right or don't measure for ovality send then back.
Talk to Henry @ supertec or John Walker or maybe the engine builder your got the core from,they should point you down the right track.
Yes you need a line bore as your bearing saddles are off square to the centre bore ,hope your countershaft journal checks ok as copper makes a crappy running surface...good luck ,looks like you bought a good core

Posted by: mepstein Jul 17 2017, 07:29 PM

QUOTE(porschetub @ Jul 17 2017, 09:23 PM)

There was bad batch's of rod bearings from Glyco for many years and from what I read they were rather poorly made.
Some of the key players in the engine business went to Clevite (Mahle) bearing for this reason,however many said the genuine Porsche (Glyco) were better than standard off the shelf ones....but more spendy for a reason perhaps ?.
Its seems folks check rod bearing install after being fitted to the rods,if the don't look right or don't measure for ovality send then back.
Talk to Henry @ supertec or John Walker or maybe the engine builder your got the core from,they should point you down the right track.
Yes you need a line bore as your bearing saddles are off square to the centre bore ,hope your countershaft journal checks ok as copper makes a crappy running surface...good luck ,looks like you bought a good core

Posted by: Mark Henry Jul 17 2017, 07:49 PM

To re-process used bearings with DFL first thing is they have to be in spec to start with.
Copper isn't always bad, OE mains you can see the copper on the thrust surface right out of the box new, but copper on the main surface they're done. With some of the intermediate thrust shells, even the surface is copper.

DFL won't replace lost material, fix scratches or wear, as it's only .0002-0004 thick and I think the .0004 is optimistic.
Also once you say "case line bore" I say "new bearings".

I haven't seen a full set of mains worth saving on a mag case yet, but I have done a few sets from aluminum cases with good results. I believe it's a combo of the AL case not shifting like mag and the later 9 bolt cranks don't bend as much.

DFL coatings are perfect for new as it helps protect your bearings upon break in first start and every time you start the engine when you have no oil pressure, especially after storage.

Posted by: Mark Henry Jul 17 2017, 07:59 PM

BTW keep your #8 if it's in spec, get it coated.
Some of the new #8 I've seen are whacked. One engine I returned the new #8 bearing twice before going with a used DFL coated bearing.

I got one new R&S german #8 standard bearing and it was something like .5mm out of spec. Total garbage, a real WTF moment.

Posted by: porschetub Jul 17 2017, 10:48 PM

QUOTE(mepstein @ Jul 18 2017, 01:29 PM)

QUOTE(porschetub @ Jul 17 2017, 09:23 PM)

There was bad batch's of rod bearings from Glyco for many years and from what I read they were rather poorly made.
Some of the key players in the engine business went to Clevite (Mahle) bearing for this reason,however many said the genuine Porsche (Glyco) were better than standard off the shelf ones....but more spendy for a reason perhaps ?.
Its seems folks check rod bearing install after being fitted to the rods,if the don't look right or don't measure for ovality send then back.
Talk to Henry @ supertec or John Walker or maybe the engine builder your got the core from,they should point you down the right track.
Yes you need a line bore as your bearing saddles are off square to the centre bore ,hope your countershaft journal checks ok as copper makes a crappy running surface...good luck ,looks like you bought a good core

I believe Porsche actually checks their bearings before sale and puts a small stamp on them.

Posted by: Optimusglen Jul 18 2017, 06:41 AM

Thanks for the replies guys, yes definitely back on the path of new bearings with all of the case work. Mark Henry thank you for the explanation, makes perfect sense.

Going to start taking some initial measurements tonight.