Leakdown test - Exhaust valves leaking

[clinebarger]

I thought 10% leakdown was really good? Is this 10% purely from the valves, or total - ie you did a wet leak down.

Unless there was some other compelling reason to take the head off, I wouldn't personally.

FWIW - the instructions always say to do a leak down with the engine warm, but no one ever does.

I install many used engines, No choice than to do it cold....A good engine will return low leak-down rates.

 

[Spetz]

I thought 10% leakdown was really good? Is this 10% purely from the valves, or total - ie you did a wet leak down.

Unless there was some other compelling reason to take the head off, I wouldn't personally.

FWIW - the instructions always say to do a leak down with the engine warm, but no one ever does.

That's ~10% total leakdown on a cold engine.
That's why I was asking, the results are good, but part of that leak is from the exhaust valves. On all but 1 it is imperceptible. On one I can hear it.

The engine is not in the car so no choice but to do a cold leakdown. In any case, I was only using a leakdown tester to keep the valve springs up while I took the springs out to change valve stem seals. It was due to this that I found the leak issue(?)

 

[SC Maintenance]

I install many used engines, No choice than to do it cold....A good engine will return low leak-down rates.

What do you consider "low" leak down - just for future reference? I was taught 20% is still decent?

 

[PontiacHO]

Valve guides worn can also cause valves to not seat squarely. If it was running ok with exception of oil usage (stem seals) button it up and drive.