two questions about the compression test

[sarantis]

Hello everybody.Prior to a compression test that i should have done many months ago searching for the problem "not running at WOT" at a GM 305 1978 i 'd like two ask two things :
a)the updated service bulletin says to carry out it at room temperature.The temp in my country now is 8-10 Celcious degrees.I think room temp is 26 degrees.Is there any problem ? Does this make the minimum 100psi a little higher?
b)Supossing i find at a cylinder low compression due to an exhaust valve that doesn't close properly,so i loosen it and i verify that compression goes high.May i run the boat to check the WOT?
Thanks in advance

 

[sarantis]

Re: two questions about the compression test

room temperature in Celcious degrees=22

 

[Bondo]

Re: two questions about the compression test

Is there any problem ? Does this make the minimum 100psi a little higher?

Ayuh,.... Not really a problem....

Run the Test,+ Come on back,+ post the #s....

If you get cylinders at or near 100psi,.... Your motor is Very Tired.....
But,......
What you Want to find is #s that are reasonably Close to each other.....

I wouldn't be messing with the Valves just yet either......
Just do a Wet Test if you've got a Low cylinder,....


Btw,..... That's 3 questions not 2...........

 

[sarantis]

Re: two questions about the compression test

Thanks for replying.I suppose wet test means 3 squirts of oil ?

 

[Haut Medoc]

Re: two questions about the compression test

Yes....​

 

[Robj]

Re: two questions about the compression test

That difference in temperature will make no difference in the compression you read on your gauge. Just do as Bond-o suggested and post the numbers.

Have a great day,

Rob.