Torque addict
Supercharged
This is a continuation of the compression check thread I started here.
I know there are plenty of pictures floating around of people's rebuilds but I thought I'd add a few more. I'll ask most of my questions here instead of in private conversations so more people can benefit and learn. I've never done anything like this so please bear with my ignorance.
The cause of my low compression in cylinder #1 and resulting excessive blow by, which causes tons of oil to spew out the crankcase vent, is clearly seen in the following pics... broken 2nd and 3rd piston lands. All 7 pieces were still perfectly attached to the piston when I pulled it out and there appears to be no damage to the liner. There are burn marks on the liner but they are smooth and no worse than the ones I’m seeing on cylinders 2 and 3 which don’t have any problems. I was surprised to see the compression ring gap on all 3 pistons still well within tolerance.
Cylinder #1 liner
Cylinder #2 & 3 liners
Now I need to decide do I just replace this one piston with a replacement OEM or do I spend the money on a set of new JE pistons with stronger lands? After pulling the first piston I was hoping I’d see something similar on one of the others to help justify going aftermarket on all three.
When doing the valve check I found more than half were out of spec. I couldn't get my .04mm feeler under a couple of the intakes and one of the exhaust valves was at .31mm. Any tips on getting the shims off for measurement and replacement? I'm asking before I've even tried. Hopefully it's rather simple.
The head bolts seemed extremely tight. I will most likely buy the Carpenter ones that don't stretch even though they're kind of spendy. They seemed so tight I started wondering if they were reverse threads. I was just waiting for one to snap but I got them all eventually following the release pattern in the manual. I just want to confirm that I do have the OEM's now. Can someone comment on that based on this head bolt pic? The head did come off once before I bought the bike.
All three connecting rods have the word "distorted" written on them. All I can say to this is WTF? Any ideas on this one guys?
Exhaust valves in the #1 cylinder with the bad piston reveals a rich mixture. So did the plugs. I'm guessing less air is getting pulled in due to the lower compression but since it's a turbo the air is actually getting pushed in. In any regard I'm guessing it didn't look like this before the piston broke and is a result of the lower compression. Any thoughts on that?
My head gasket has a copper film all over it. I'm guessing this is copper anti seize compound? Is this common practice on a head gasket? I was going to buy some nickel anti seize for the exhaust bolts. Don't have any copper anti seize.
The manual mentions using molybdenum disulphide grease in a few places when putting things back together. Would any high temp high pressure grease be just as good or must it say molybdenum disulphide? What are people using for this?
Thanks for any answers or comments.
Also, much thanks to Scott (Warp9.9) for the tip on disconnecting the connecting rod from the crank and pushing the piston out from the top. Why anyone would remove the pistons by the method shown in the service manual is beyond me.
I know there are plenty of pictures floating around of people's rebuilds but I thought I'd add a few more. I'll ask most of my questions here instead of in private conversations so more people can benefit and learn. I've never done anything like this so please bear with my ignorance.
The cause of my low compression in cylinder #1 and resulting excessive blow by, which causes tons of oil to spew out the crankcase vent, is clearly seen in the following pics... broken 2nd and 3rd piston lands. All 7 pieces were still perfectly attached to the piston when I pulled it out and there appears to be no damage to the liner. There are burn marks on the liner but they are smooth and no worse than the ones I’m seeing on cylinders 2 and 3 which don’t have any problems. I was surprised to see the compression ring gap on all 3 pistons still well within tolerance.
Cylinder #1 liner
Cylinder #2 & 3 liners
Now I need to decide do I just replace this one piston with a replacement OEM or do I spend the money on a set of new JE pistons with stronger lands? After pulling the first piston I was hoping I’d see something similar on one of the others to help justify going aftermarket on all three.
When doing the valve check I found more than half were out of spec. I couldn't get my .04mm feeler under a couple of the intakes and one of the exhaust valves was at .31mm. Any tips on getting the shims off for measurement and replacement? I'm asking before I've even tried. Hopefully it's rather simple.
The head bolts seemed extremely tight. I will most likely buy the Carpenter ones that don't stretch even though they're kind of spendy. They seemed so tight I started wondering if they were reverse threads. I was just waiting for one to snap but I got them all eventually following the release pattern in the manual. I just want to confirm that I do have the OEM's now. Can someone comment on that based on this head bolt pic? The head did come off once before I bought the bike.
All three connecting rods have the word "distorted" written on them. All I can say to this is WTF? Any ideas on this one guys?
Exhaust valves in the #1 cylinder with the bad piston reveals a rich mixture. So did the plugs. I'm guessing less air is getting pulled in due to the lower compression but since it's a turbo the air is actually getting pushed in. In any regard I'm guessing it didn't look like this before the piston broke and is a result of the lower compression. Any thoughts on that?
My head gasket has a copper film all over it. I'm guessing this is copper anti seize compound? Is this common practice on a head gasket? I was going to buy some nickel anti seize for the exhaust bolts. Don't have any copper anti seize.
The manual mentions using molybdenum disulphide grease in a few places when putting things back together. Would any high temp high pressure grease be just as good or must it say molybdenum disulphide? What are people using for this?
Thanks for any answers or comments.
Also, much thanks to Scott (Warp9.9) for the tip on disconnecting the connecting rod from the crank and pushing the piston out from the top. Why anyone would remove the pistons by the method shown in the service manual is beyond me.
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