compression check

[Radiant-Designer]

just while i was at it I decided to do a compression check on my L20B.... plugs 1, 3, and 4 were all 170... plug 2 was 155.... should I have any concern? Its within the 30% my manual says it should be, just seemed off that 3 out of 4 matched, and one was off... it was the one that the spark plug looked brand new in too, the others didnt look bad, just like they were used.

[I'm BLUE]

No ,,, that's good yo !!! :D ,,, that's just under 10% variance ,,, :)

 

I wouldn't hesitate to drive that ,,, 170/155/170/170 !!! :cool:

 

Change oil periodically and filter ,,, Adjust valves ,,, Check Timing Chain Tension ,,,, and go !!!

[metalmonkey47]

sounds pretty typical for a datto motor to me. But like DTP said, do your adjustments and double check! ^^^ An over tight valve will cause a lower compression on that cylinder. Even though, that's probably not related, it never hurts to do it.

[datzenmike]

... plug 2 was 155.... it was the one that the spark plug looked brand new in too, the others didnt look bad, just like they were used.

 

Does the motor over heat or use coolant?

[Radiant-Designer]

doesnt overheat at all. I am loosing a little coolent, not much, but I think that was from it leaking where the thermostat housing and the upper water inlet met, I changed the whole housing and put all new gaskets on and hoping that fixed everything.

 

Ill check the valves this weekend. I tried doing it last weekend but I am used to pushrod motors so I didnt know you checked it at the lobes of the cam, Like I said good thing I knew something was off and put it all back together before adjusting anything ;)

[datzenmike]

The reason I ask is because the low cylinder also has a clean plug. Usually if the gasket leaks coolant into the cylinder it will steam clean it and everything in there like the plug. The leak has to be pretty bad though.