Valve collision problem |
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Valve collision problem |
thomasotten |
Jun 30 2018, 08:03 PM
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#1
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Senior Member Group: Members Posts: 1,545 Joined: 16-November 03 From: San Antonio, Texas Member No.: 1,349 |
I am having a bit of a problem with my latest 2 liter build. Basically, valves are colliding with pistons after warm up during break in. A valve got stuck and the pushrod actually fell off the rocker.
The heads were redon by RIMCO. After the problem happened, I pulled the heads, and there was clear indication of valve collision, and I had a valve stuck open. The head with a problem was sent back to RIMCO. Reinstalled. What happened this time is the engine start up from cold, runs fine. But then I can hear the taping of collision again. The taping is accompanied by a chirping sound that sounds like something is dragging. I think it must be the valves dragging and closing too slow. I have a deck height of .065. This is essentially a stock build, stock camshaft, etc. Any ideas? Is this perhaps a valve stem lubrication issue? |
Mark Henry |
Jul 1 2018, 02:33 PM
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#2
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
I'd check the clearance of the guides, most shops use a Go-No Go gauge, but it as simple as feel for an experienced machinist, if it catches before the spring goes on it will seize when hot.
Another cause for this is bad gas, varnish, new engine always use brand new gas. This could just be caused by your issue, but that is lean city, brown exhaust valve, bright white electrode. |
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