Lower than expected cold crank compression
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From: poway
Did you check the ring gaps?
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From: Jacksonville FL
I wouldn't worry about your compression. If you don't like my opinion, fine with me, I don't care.
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From: poway
I didn't see anything about oil. I was talking about compression. I repair car engines, I never did bike engine, but engine is engine, doesn't matter if it is lawn mower or Corvette. They are pretty much the same.
I wouldn't worry about your compression. If you don't like my opinion, fine with me, I don't care.
I wouldn't worry about your compression. If you don't like my opinion, fine with me, I don't care.
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Joined: Jan 2017
Posts: 894
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From: Jacksonville FL
I am a car mechanic (kind of) and I do everything, including transmissions and paint, but my main specialty is engines repair. I never repaired Corvette engine but they are old style pushrod engines, not much changed in last 50 years.
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From: poway
Do you bore cylinders, replace valve seats, do valve jobs, mill heads? Any performance work? Degree cams? CC Heads / pistons other blue printing stuff like balance the crank? Do you tune fuel injection? Tune carbs even? What kind of performance work do you do?
It's not hard to bring a production motor back to spec tho you still may need to cut valve/seats bore cylinders, etc. When you want to squeeze a little extra out you can start changing parts but the process can quickly become more than just buy parts and replace what you want. Clearances need checking, cranking pressures set, intake and exhaust flow set.. Etc. Still you can run into cranks that twist, rings that don't seat, issues with poorly designed after market pistons, improper cylinder finish etc.
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From: poway
A lot of times the rings will need filing.. Especially on the after market stuff..
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From: WA State
Got 70 miles on the new rebuild. Been watching the timing gauges on the PV and it was pulling 5-7 around 5k on some very hard back road wot pulls. Looks like it should hold up on a dyno now.
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From: Jacksonville FL
considering your engine guy didn't find anything wrong with it, you did work for nothing.
It happens, a few months ago I removed/installed Toyota Sequoia V8 engine 3 times.
Compression has to be checked on hot engine. Manuals usually specify not more than 10% compression difference between cylinders. I wouldn't do anything if compression were 20% different. It wouldn't be noticeable.
It happens, a few months ago I removed/installed Toyota Sequoia V8 engine 3 times.
Compression has to be checked on hot engine. Manuals usually specify not more than 10% compression difference between cylinders. I wouldn't do anything if compression were 20% different. It wouldn't be noticeable.
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