89 951 engine overhaul

[chris white]

I would toss that one. Very rare to have any scoring. Used ones are pretty cheap

[gruhsy]

Have you considered oil shedding coatings?

Doing it with my engines as it’s cheap and easy to do myself.

I had not really even known it was an option. Do you have any resources? The stuff I found on a cursory search was mostly just services offered.

I'm no expert (at all) on oil pumps. When I built my motor, the pump looked like that so I just bought a new one from Porsche. I think it was like $500 back then, but no idea if they are even available any more. I'd be worried about adding too much clearance by machining it, and having it pump less than it should...??

Yeah, they're about the same price from dealers. Closing in on 2x from other vendors

Here is one good example.

https://techlinecoatings.com/new-intern ... -coatings/

[four0four]

I think I'll keep things (relatively) simple this go-'round. Enough of this is already new ground for me...Maybe the next motor

Lightly contradicting that, I've been somewhat taken by those fancy "cut ring" head gaskets. Seems they've quite a history in BMW motors, and I was able to find at least a bit of evidence of a vendor supplying something similar for 944s like 18 years ago. Looks like SCE p/n CR330137 (102mm bore) is what I'd pick up, though for some reason the 105mm option is more widely available. Figure it'll at least give me some peace of mind about not prepping the block for an MLS option.

Anyway: Final balancing and picking up the motor tomorrow

Going to go over all the clearances and clean everything out, but it'll be great to finally start putting stuff together.

[stitch2k1]

I'm chiming in just cuz I'm selling 404 here an oil pump bc I have two spares with no need.
Any reason these SHOULDN'T work?

944 107 111 1R
944 107 111 3R

I know there's one revision of it that uses a different main seal, but they are otherwise functionally identical yes?
Tyia

[chris white]

I'm chiming in just cuz I'm selling 404 here an oil pump bc I have two spares with no need.
Any reason these SHOULDN'T work?

944 107 111 1R
944 107 111 3R

I know there's one revision of it that uses a different main seal, but they are otherwise functionally identical yes?
Tyia

Very early 944na pumps used a different diameter seal, otherwise they are all the same internally

[four0four]

944 107 111 1R is the late casting, 944 107 111 2R is what I have (and what I've seen on late model S2/Turbos and replacement pumps) and 3R....I'm not sure, but I am curious. Assuming it's not a transcription error!

[stitch2k1]

Very early 944na pumps used a different diameter seal, otherwise they are all the same internally

Yeah Ik that. I sadly don't have one else I'd give 404 one.

Below is stolen from a Rennlist thread.

Older oil pumps have a thicker casting where the timing belt tensioner stud goes through it and requires the proper shouldered nut tightned against the oil pump, then the tensioner goes over the stud against the nut. I believe this pump was pre automatic tensioner.

Later oil pumps (87and later) have a thinner casting where the stud goes through and requires the nut tightned against the oil pump and then a spacer that is approx 1/4 inch thick placed on the stud and then the tensioner placed on the stud.


The 2 pump numbers are
944 107 104 9R
944 107 111 3R

Pump 104 has a thicker casting where the timing belt tensioner stud goes through it and requires the proper nut tightned against the oil pump, then the tensioner goes over the stud against the nut.

Pump 107 111 3R has a thinner casting where the stud goes through and requires the nut tightned against the oil pump and then a spacer that is approx 1/4 inch thick placed on the stud and then the tensioner placed on the stud.

[four0four]

Picked up the motor from Bearing Services yesterday! Everything they touched looks great (so, the deck doesn't look great, probably should've cleaned that up first...will figure that out) & this little nick (outside of ring travel, so whatever):

23-01-28 15-27-44 2047.jpg (2.67 MiB) Viewed 1079 times

I think the bores look awesome


If you'll remember, I asked them to fix up some water pump studs. They cut and fit a custom insert (after digging out someone else's extractor!):

23-01-28 15-28-20 2051.jpg (4.64 MiB) Viewed 1079 times

(I've never seen anyone stake a plug like that)

Also, I think I need a new down pipe:

23-01-28 15-53-22 2052.jpg (2.9 MiB) Viewed 1079 times

Anyhow, this is exciting and all...but I really just need to finish cleaning the garage and prep it for assembly before anything else!

[Thom]

Looking good. That's how fresh Alusil bores should look like.

The water pump area reminds me of a friend who slightly machined down his 100mm bore block like yours to make room for the larger impeller water pump used on 104mm blocks, in order to improve cooling.

[chris white]

staking the plugs is an old school deal, I still do that to all plugs just in case!