#4 Cylinder intake valve stuck open |
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#4 Cylinder intake valve stuck open |
gnomefabtech |
Mar 19 2023, 09:20 PM
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#1
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Member Group: Members Posts: 97 Joined: 27-December 22 From: Los Angeles Member No.: 27,063 Region Association: None |
So I'm trying to resurrect this 76 (or is it a 75?) that I just bought and it doesn't have compression on the #4 (rear right) cylinder. After some tests with compressed air it's clear that the intake valve isn't closing. I pulled the valve cover and the rockers move OK but that valve does not close all the way. Everything else looks good.
I have a lift but was wondering if I could pull that head without dropping the engine. It looks like there is room but I'm not sure about the engine tin etc. Seems like either the valve is bent or somehow stuck and maybe I can just fix the one thing there. Anyone pull heads while the engine is still in the car? |
gnomefabtech |
Mar 19 2023, 09:37 PM
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#2
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Member Group: Members Posts: 97 Joined: 27-December 22 From: Los Angeles Member No.: 27,063 Region Association: None |
Thanks for the reply. I'll pull off the intake and maybe be able to see if the seat is dropped. No idea if it ever ran in this condition. I never ran it.
Are dropped seats a common thing on these? The motor looks like it's never been opened and is totally stock. |
930cabman |
Mar 20 2023, 05:45 AM
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#3
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Advanced Member Group: Members Posts: 3,038 Joined: 12-November 20 From: Buffalo Member No.: 24,877 Region Association: North East States |
Thanks for the reply. I'll pull off the intake and maybe be able to see if the seat is dropped. No idea if it ever ran in this condition. I never ran it. Are dropped seats a common thing on these? The motor looks like it's never been opened and is totally stock. Yes, the valve seats do fall out of their recesses with these aluminum heads. Being 1/2 century old, chances are the motor has been opened at some point. Drop the engine and remove the heads as a start. |
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