crossflow compression numbers...

[nadornati]

hey guys.. checked the compression on my 1987 evinrude 175 today... its a crossflow motor.. i got 86 straight across the board... ive read that its supposed to be between 80-90, 110-120??? idk whats right.. help

 

[emdsapmgr]

Re: crossflow compression numbers...

Your compression sounds normal. You have a big bore (160 cubic inch) engine with the bathtub heads. The 110 figure is typical in the earlier small bore (149 cubic inch) 150/175 crossflow flatbacks with factory high compression heads. They look the same, but have different internals and are hp rated differently.

 

[talley2191]

Re: crossflow compression numbers...

How long did you let it warm up before getting those numbers?

 

[nadornati]

Re: crossflow compression numbers...

no spark to starboard side, im guessing its the power pack if the port side has spark to all cylinders and i just put a new stator on it...
so i didn't run it at all prior to compression test...