Quote:
Originally Posted by Bill Douglas
My car being your car's twin brother separated at birth, I'm dying to know what was done in the rebuild?
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Long story short.. I have had the car for 7 years, drove it 60000km, and it has 261000km (163000 miles) in odometer. I have known that there will be need for at least top-end rebuild. I don't know the full history of the car, but I have heard uncertain rumors from the friend of the guy how imported the car to Finland in ~1990 that there has been "money shift" accident and (some of the) valves were replaced back then. Otherwise the engine has not been opened, not that I know.
In september, I was driving on highway and after some harder acceleration my friend called me (he was driving behind) that my car smokes. I could not see that from mirrors, and there was not any weird noises, oil pressure amount and temperature were good so I drove it home. There I realized that left side has major oil leak. There have always been some minor leaking (drops in valve cover lower corners), but this was now something more serious. I did compression leak down test and it was clear: cylinder #2 was not holding pressure. So.. time to rebuild.
Engine was dropped and disassembled and it turned out that the piston #2 was broken. There were pieces of metal missing from grooves that hold the piston rings and rings were broken as well. Luckily, that didn't cause any other damage: all pieces were found from the bottom of the case and the cylinder was in perfect condition. The root cause was not found, there were no evidence of lean mixture, bad injector, or anything like that. Maybe it was just because stuck rings due to all the deposits?
Anyway, while already in there, it was clear that the engine must be fully overhauled now. In addition to the broken piston, the only real fault was broken intake valve spring in cylinder #4 (not the same as the failed piston). Otherwise everything was in good shape, but naturally a lot of burnt deposits in pistons, heads and valves. Most of the valves were worn under size, so they were all replaced with new guides and seals. Heads were blown clean and machined. Crank, connecting rod, and ims bearings were all replaced even though the original 38yo bearings were so good that the engine could have been assembled with them! The engine was assembled with a set of new Wössner 10.5:1 CR forged pistons. Original cams, original bosch K-Jet injection and ignition. The Dansk dual-in-single-out stainless steel pre-74 style exhaust was there already when I bought the car.
And how it runs now.. Check the video here (sounds on!):
https://www.youtube.com/watch?v=Z2t9Nyinj04
Some pictures:
Failed piston:
https://imgur.com/a/YuXAhrh
New pistons:
https://imgur.com/a/jva4r0C
Disassembled parts, machined heads:
https://imgur.com/a/aDhpqjQ
Rebuild in progress (RIP):
https://imgur.com/a/iOSHeob
Rebuilt engine:
https://imgur.com/a/9sgLNTd
On lift 350km later:
https://imgur.com/a/nYLFYqS
Bonus:
Couple of hours before the disaster:
https://imgur.com/a/GFLgIlK