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compression low on new engine


braden

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Sorry to sound harsh but how does one obtain a "fresh" rebuild with bent valves? If its truely a new build surely a visual examination of the head before assembly would point this out. If it was really rebuild logic says drop out valves replace stem seals etc examine valves cut them back into seats check seal etc.

Only thing I could forsee is if the cam belt was incorrectly installed motor not tuned over by hand to check for binding etc and just cranked straight away.

If this is the case you may well have ruined the pistions in the process more than likely broken valve guides and possibly ruined the seats by bashing the valves into them.

Dont take it to heart but this dosent make sense to me. If one is competent enough to rebuild a motor measuring and following close tolerances then one should also know how to time up motor to avoid such catastrophe for occuring to begin with

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Sorry to sound harsh but how does one obtain a "fresh" rebuild with bent valves? If its truely a new build surely a visual examination of the head before assembly would point this out. If it was really rebuild logic says drop out valves replace stem seals etc examine valves cut them back into seats check seal etc.

Only thing I could forsee is if the cam belt was incorrectly installed motor not tuned over by hand to check for binding etc and just cranked straight away.

If this is the case you may well have ruined the pistions in the process more than likely broken valve guides and possibly ruined the seats by bashing the valves into them.

Dont take it to heart but this dosent make sense to me. If one is competent enough to rebuild a motor measuring and following close tolerances then one should also know how to time up motor to avoid such catastrophe for occuring to begin with

Ohh harsh!

Just curious to know if the compression tester you used was home made also? Or have you checked it on a known good engine?

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It would need to be a highly modified engine to bend valves or a combination of 2.4 and 2.0 parts.

Or more simply, valves have not hit pistons. Jet valves (which I completely forgot about) are usually left alone but if removed are always blanked off.

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nah and not very likely to bend all valves and there a no contact engine so if cambelt breaks don't usually bend valves on them.think iv found the problem guys had bottom end rebuilt by the motor builder.then hes put the head on and the head bolts were hardly even tight when should be tight as fuck to a torque setting

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