Engine compression !?

[mxguy132]

What should be a good compression on a 4.3 omc cobra that has little over 3 hundred hours on it??
Thx for any input

 

[Don S]

Re: Engine compression !?

To put 300 hours into perspective, if you drove your car 300 hours and averaged 35 mph, you would go 10,500 miles.

You need to do a proper compression test to find out the condition of your engine. Cylinders being close in value to each other is more important that "Book" value.
Here is how to do a compression test that means something.

 

[jerryjerry05]

Re: Engine compression !?

Your guage might read differntly than mine.So 100# on yours could be 130# on mine.
Like Don says they need to all be close to each other.Within 10-15# of each other.

 

[Bondo]

Re: Engine compression !?

What should be a good compression on a 4.3 omc cobra that has little over 3 hundred hours on it??
Thx for any input

Ayuh,.... I'd think you oughta be seein' 150psi. or higher...
But, as noted, Close numbers are more important than high numbers...