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? |
euro911 |
Jul 1 2018, 04:29 AM
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#2
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Retired & living the dream. God help me if I wake up! Group: Members Posts: 8,849 Joined: 2-December 06 From: So.Cal. & No.AZ (USA) Member No.: 7,300 Region Association: Southern California |
Deck height at the top of the barrels is one thing, but it sounds like maybe the shop cut the shoulders (where the top of the barrels slip into the head(s) too deep (IMG:style_emoticons/default/unsure.gif)
You may need to install shims between the base of the barrels and the case, or get another pair of heads (IMG:style_emoticons/default/confused24.gif) |
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