bent push rod confirmed
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Joined: Jul 2007
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bent push rod confirmed
In my last post i was concerned about possible bent push rods in my 87- although it turned out the ones that I suspected were probably ok. When I got to #2 exhaust it was clearly bent. I think the car was over-revved.
I checked all push rods and no others were bent. 3 did bind when spinning them. I replaced all 4 push rods and rocker arms with oem replacements.
Since all push rods were out I reset "valve lash" on all using the Chev shop manual. I used recommendations from the forum about how many turns after the push rod began to spin less freely (1/2 turn extra for new and 1/3 turn for existing).
Started car and it idles fine and accelerates normally but sounds ****** under hard acceleration. No smoke. Plugs look fine. No vacuum lines left open.
Did I miss something in setting lash? I did notice the directions seem to only talk about new push rods.
Tested compression this morning and all cylinders match what they read last fall. That should rule out a bent valve (shouldn't it?).
Anything else that I should check for while I have the valve covers off?
Thanks!
I checked all push rods and no others were bent. 3 did bind when spinning them. I replaced all 4 push rods and rocker arms with oem replacements.
Since all push rods were out I reset "valve lash" on all using the Chev shop manual. I used recommendations from the forum about how many turns after the push rod began to spin less freely (1/2 turn extra for new and 1/3 turn for existing).
Started car and it idles fine and accelerates normally but sounds ****** under hard acceleration. No smoke. Plugs look fine. No vacuum lines left open.
Did I miss something in setting lash? I did notice the directions seem to only talk about new push rods.
Tested compression this morning and all cylinders match what they read last fall. That should rule out a bent valve (shouldn't it?).
Anything else that I should check for while I have the valve covers off?
Thanks!
Instructor
Joined: Jun 2011
Posts: 182
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From: Bowling Green Ky
we assume the valves floated, no way to know, probably not tight valve guides.
the number of turns recommended in fsm is what I would use. In my days of building it was one full turn, and what I used. same now in my 91 fsm. not sure where the other methods came from. people who were smarter than the engineers, I reckon.
lifters should stay with the cam lobes, of course. don't know what the noise is without more info, was it being driven? what?
Last edited by stoydido; Jul 30, 2011 at 05:51 PM. Reason: spell
Race Director
Joined: Apr 2003
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From: moraga ca
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