well.. the last thread ended up not being about its compression...
manual says 85-90 lbs of compression at 400 rpm... i am assuming that 400 rpm is just turing over.. right..?
it also says it may vary due to decompression... so how do i know what it really has for compression?
and while i am at it.. how many lbs. can i go before i run race fuel?

 

The compression will vary with the RPMs do to the decompression mechanism. It must turn off at 400rpm thats when you will have full compression and you will get an accurate reading... 85-90 thats it!?![img]i/expressions/face-icon-small-shocked.gif[/img]

basically you just have to turn the engine over faster then 400rpm and you will then know your compression psi...

 

thanks guys....
and would a bend vavle lower compression?

 

Absolutely! If you have any kind of lack in seal that is allowing pressure to leak it will most definately lower your compression. Remember all four of your valves are supposed to be closed on a compression stroke. If one is not completely sealed thats definatley a way for the pressure to leak out.

 

The motor should be at 130PSI but it is becuase of the decompression valve that 90PSI @ 400RPM (+/- 5LBS). The valve dosen't shut off at 400 RPM, 90PSI is the estemated compression at that RPM. There also is some warning about attempting to bypass the valve and disloging something LOL, kinda skipped over the safty note. if your really interested I can post it.

 

lol.. na i read that BS too... so to check my compression i just put the tester in the hole and turn it over right...? very simple... but does it go passed the decompression stage so i can see what i have for compression? i need to check.

 

Yeah you just remove the plug screw in the tester, The thing is you have to turn the engine over fast enough so that its out of the decompression stage...

 

ya.. i know...
so will the starter turn it over fast enough?

 

It should, make sure your batt is fully charged... You can tell just by looking at the tester if its not going fast enough and its still in the decompression stage..

Does the pred have a back up start? like a pull start?

 

the only type of back up it has is push and drop the clutch