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: 1,544 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? |
thomasotten |
Jul 1 2018, 05:18 PM
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#2
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Senior Member Group: Members Posts: 1,544 Joined: 16-November 03 From: San Antonio, Texas Member No.: 1,349 |
It is hard to make a good photo of this, but looking
down the guide, there are areas that look non uniform. Like the way wood looks when you have lightly run a chisel over it. Again, cause or effect? I’m leaning towards imperfect guide reeming. Attached thumbnail(s) |
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