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Engine not idling

letterman7

Honorary Admin
Squirt some oil in the low cylinders and crank it over a few times to get your readings. If the pressure comes up, it's rings. If it stays the same, it's valves. A leakdown test would tell you if it's valves as well. I'd throw a borescope down the hole and check the sides of the cylinder(s).
 

vpogv

Active member
Thanks letterman, that's definitely the route I'm going. Oil first then leak down. Updates to come.
 

vpogv

Active member
Dead exhaust valve on #1 was the culprit. After teardown the thrust play was .039 which was a bit far out of the .006 spec so the engine was shot.

Once I go a replacement engine I found that the idle was still fighting me unless I backed out the idle jet 1/4 of a turn. Once I did that it idled great. I believe the issue is the 55 jet is either too small or that it was over tightened at some point causing the flow to suffer. I ordered a new jet and waiting for a few other engine parts to arrive before I test.
 

letterman7

Honorary Admin
Geez.. welp, at least you found the issue. Shame you went and found another engine... cylinder heads with valves already installed are to be had anywhere.. and you could have bumped up the displacement with a jug kit :)
 

vpogv

Active member
Geez.. welp, at least you found the issue. Shame you went and found another engine... cylinder heads with valves already installed are to be had anywhere.. and you could have bumped up the displacement with a jug kit :)

True but even with the heads my block was shot with that much play.
 

letterman7

Honorary Admin
Just the crank.. which would have to be changed anyway. And that thrust play may have been a worn (or wrong) pushrod.. it happens.
 

vpogv

Active member
Just the crank.. which would have to be changed anyway. And that thrust play may have been a worn (or wrong) pushrod.. it happens.
Fair enough but funds weren't there for a bigger engine build and the newest engine just happened to be where I took the heads for a potential rebuild. It all worked out (give or take).
 
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