Losing coolant mysteriously

[thedoctor]

About 1000 miles ago, I replaced head gaskets and had a valve job on my 1983 dl, ea81. Engine is running great but I have a persistent front oil leak, and a more worrisome coolant disappearance of about 1 qt / 100 miles. No visible external leaks.

 

Compression pre-repair: 1:90, 2:102, 3:38, 4:118 I did find evidence of HG failure on cyl 3.

 

Compression post-repair: 1:165, 2:157, 3:167, 4:160. Something is going on over there on the left side. Plugs 2 and 4 show darker than 1 and 3. See attached photos. Sorry for out of focus, but you can still see the difference when I hold them side-by-side.

 

I did go back and redo the intake manifold gaskets, which made no difference. I would appreciate any suggestions as to my next move.

[thedoctor]

Eureka. I found the problem... and it's me! But seriously, I decided to have another thorough look see at the entire situation. I just let the engine run and I stood there... and lay there gawking and searching for even one drop of coolant coming from anywhere. Nothing.

 

And then for some unknown reason I reached in and grabbed the accelerator cable and pulled. And bless me soul there was a wee leprechaun peeing out from under me carburetor. I let off the accelerator and the green stream stopped! The coolant bypass hose had a slit in it that would only open up under higher pressure!

 

Now I know y'all knew very well my compression numbers did not tell a tale and my spark plug differences were nil. Y'all were just being polite. I guess we see what we're afraid to see. But I am one happy guy right now.

Edited July 13, 2012 by thedoctor

[rdweninger]

So what about the persistent front oil leak? Did you replace the front main seal, cam seals / o-rings, oil pump, when you did the HG's?