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Tapping and rough Idle

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Old 11-27-2010, 01:31 PM
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Default Tapping and rough Idle

I had a slight tapping sound and a rough idle. I figured I had a bad lifter. I took the top of the motor apart getting to the lifters and when I got to the push rods I pulled all the push rods out, 1 was bent and another was bent and broke.

Any idels of what would cause this?

Thanks Guys!!!
Old 11-27-2010, 02:28 PM
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If the pushrods are OEM any over-rev event (late upshift or premature downshift) can cause bent pushrods. It is not a bad idea to replace OEM with hardened pushrods even if you not doing any other modiciations.
Old 11-27-2010, 02:38 PM
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Originally Posted by Darkman
If the pushrods are OEM any over-rev event (late upshift or premature downshift) can cause bent pushrods. It is not a bad idea to replace OEM with hardened pushrods even if you not doing any other modiciations.
Sorry to threadjack,
But would bent pushrods cause a sewing machine type sound on the bottom end? I cant really tell it may be my exhaust as I only stuck my head under there for just a minute or so.
I may have to do my valve seals soon and was just wondering if I should go ahead and do this. Not to mention my car is a stick and has high mileage.
Links to a good product?
Old 11-27-2010, 03:46 PM
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Noise from bent pushrods would be from the upper part of the engine, but the associated conditions could cause other sounds. A number sponsors here sell good push rods, e.g. Texas Speed, Thunder Racing, etc.
Old 11-28-2010, 03:02 PM
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Thx for the info. It has 215,000 miles so dont quess new pushrods could hurt.
Old 11-29-2010, 10:28 PM
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I think nimrod meant noisy in the lower rpms, the answer is yes to a degree. Slightly bent pushrods means that there is going to be a little more lash at the rocker arms which is where you get the tick. The reason you hear it at lower rpm however is probably just because the exhaust isnt as loud there and also with the engine at slower speed theres more time between ticks which makes them more defined. when in doubt grab some though. I think tsp has them for 109$
Old 11-29-2010, 10:35 PM
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remove your push rods out.roll your push rods on a flat surface,kitchen table or counter top.if you push rods are straight your lifters mite be bad at that high of mileage.look for broken valve springs or bad rocker arm trunnion bearing.ls1howto.com for instructions on removal of said pieces.



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