compression question

[rob willison]

with out doing a a compression test are their any sins of a compression issue? reduce rpms? smoke? any tale tell sings?

 

[Bt Doctur]

poor performance, excessive blow-by from the valve covers, ratttling sounds from loose pistons

 

[rob willison]

where would the blow by be seen?

 

[niterider64]

I have gotten a lot of help recently so here is my chance to give back. When compression gas blows by the rings they fill the crankcase where the oil is. If it is a v6 or 8 plug one of the breathers from the valve cover and put a piece of paper towel over the other breather hole while you rev the eng to about 3000 rmps. the towel will blow off and you should see blueish smoke coming from the breather if the rings are bad. You can still have low compression if the valves are not seating properly. Buying a cheap compression gauge and pulling the spark plugs is really the way to check for sure.

 

[bondo]

Buying a cheap compression gauge and pulling the spark plugs is really the way to check for sure.

Ayuh,..... I agree, Completely,.....

Blow-by will be seen in the tubes from the valve covers, to the carb's flame arrester,....
There'll be a heavy oil film on everything, 'n plenty of wind through the tube,....