PorscheFanatic202

What essentially started from just a simple overall clean and reseal has transformed to my head needs replaced and then finally to complete rebuild.

see old thread....
https://rennlist.com/forums/944-turb...h-my-head.html

At first the engine was leaking oil like a water fountain, it needed an oil cooler (old one was chopped off and lines were connected together), and the exhaust was leaky. Now that the engine is off and disassembled completely it shows how much was actually needed.

One of the cylinders is slightly gouged. Right side of the pic, looks small but it is about 0.003" deep.


I knew something was funky with the oil pan, but you can see what was done. Complete hole in the pickup tube mesh.


There was some sort of sand material in the oil cooler attach point. Coolant side.


That ****.....


Ceramics toasted on cylinder head.


One of the reference sensors was held on by wood putty.


Here is the new.....

This piston is pretty gouged. I think it should be useable since that part doesn't touch anything. What do you think?


Here is a worn rod bearing with a gouge in it. The crank magically looks ok.


See the attached images for the rest of the bearings. So far this has been pretty fun. I'm sure the installation will be a bit tougher, but i'm looking forward to get this back together.

I'm looking to get the block sent away to be repaired, but that is where I stand now. Hopefully i'll get it sent away before I head off to Survival school in Spokane in May. Good times.

Dutch944

Wauw.. That you're even doing a rebuild with sand in there! Assume you're going to have it washed very thoroughly!

What is the plan?

Rob in Oz

I'm reminded of the story about the lost tourist and the farmer: "if I was going there, I wouldn't start from here..."

That engine doesn't look like a good starting place, unless you want a boat anchor.

Rob

Paulyy

IMO.

I'd get that engine. Strip everything off it. and start scrubbing and cleaning. Replace everything that you can.
I'd be replacing those pistons too.

PorscheFanatic202

The sand is out, I plan to send this block out to the cylinders redone and the block overall checked. I will see what the pistons look like after they are cleaned. I would really like to save that expense. I'm not making a track motor, but I would like it to last a long time obviously.

PorscheFanatic202

I would like to have the cylinders nikasil plate plated and honed. That is my starting place.

What would one recommend for pistons? I would have to make that decision before I send the block out.

944meister

You could send the block off to 928motorsports and order pistons through them. They have a piston and a total seal piston ring combo that apparently works well with Nikasil bores, plus you'll be given their break-in procedure. There is also a thread here on Rennlist of a documented S2 build that went this route. Another option would be to get custom Wössner pistons through Racers Edge, which might be less expensive if I recall.

eman930

It's amazing what a parts washer will do

PorscheFanatic202

What solvent do you use in yours and what parts washer do you have? I don't want to eff up my aluminum block with a basic solution.

eman930

Honestly, it was just powder soap, in a hot parts washer that would hold the entire block.... Kept it in there for about 30min.... Then when it came out, I hit it with a gel engine degreaser and power washed it.. Super clean

eman930

This stuff works wonders... Get a couple cans, coat entire engine, let it sit for a day, power wash off... Works great!

http://www.acehardware.com/product/i...la=pla_4662678

Dutch944

Nikasil is very expensive.. I just went the normal sleeve route with mine and got a set of custom pistons, but that was because of the high hp output that mine will have to do.

Just sleeving and a set of standard pistons from Wossner or something similar will cost you the same as getting your block nikasil sleeved..


And indeed, just washing your engine block saves a lot! I did the same to mine and it looks the same as yours now! If you're not completely happy with the result you can saltblast it and than wash it again to get the most perfect result!

PorscheFanatic202

Was talking to Chris. For what I'm doing, he thinks my cylinders are fine, but one of my pistons is gouged. Are these pistons a standard size or are they stamped with a specific code? I would then just have to balance the set....just weigh each piston then make them weigh the same? Or is it necessarily more complicated like figuring out the bob weight?

cruise98

You can find the tolerance group etched on the top of the piston, and a corresponding number stamped on the block. The cylinder bore looks OK for a street engine to me, but the piston is toast. Before you remove the pistons, remove the carbon from the top of the bore, or the rings will be ruined when you remove them. This will be controversial, but if the rings are within tolerance, I would reuse them. I have re-ringed two engines without polishing the bores, one was successful and the rings never seated in the other one. Plenty of others have had no trouble, but I am never lucky with this kind of thing. The nikasil coating is very nice, but it is sort of expensive if done correctly.

You will get many different opinions on what to do next. If the bores are within spec. I would have them polished with the special paste and install fresh rings. If the bores are out of spec. you have some decisions to make. The piston pin bushings are probably worn and need replacing as well.

The sediment in the oil cooler cavity looks like the coolant was not changed regularly. Not too surprising considering some of the other "repairs" the PO made.

If you can find a used engine known to be in good condition, that is probably the quickest and least expensive route to take. If you can find one with good compression and leak down numbers...

doabarrelroll

Steel sleeves are easy if you want to stick with your current block. Figure it will run you $2-2.5k when it's all said and done. Mine turned out really nicely. I'm using the original pistons and stock piston rings.