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How much does the engine move?

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drooartz

drooartz

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I'm still trying to track down an odd noise, and have a question.

How much should the engine move (shake, vibrate) under load. Say, measured at the valve cover?

I'm trying to figure out what *might* be vibrating and hitting something to make the noise. I'm not convinced that it is an intake/exhaust problem -- though it still could be.

I'm wondering if the header might be knocking against the frame, but it's hard to see so I'm wondering how much clearance there needs to be where the header goes through the frame.
 
I have never seen an engine move more than 1/4" total.
1/8 each way and that is when it's running rough.
If your engine moves 1/2 inch total from side to side, I would check the flywheel not being tight or somehow out of balance.
As for what could be knocking, check the clearance hole where the header passes
through the frame hole, that hole needs to be enlarged for LBC headers.
Sometimes they knock on the frame pleat, cut it or bend it out of the way.
 
My hood makes a knocking noise from vibration, so does dad's Willys jeep (drove him NUTS for years. Does the bonnet rattle?
 
bonnet buffers

I had the same thing, found I was missing some rubber bonnet buffers.
 
Drew, it could be the header is touching the frame under rpm, you should be able to mock in the garage in neutral while reving. We put steady rods on the race engines for this sort of thing.
 
I haven't checked how much it is moving, just wanted to know what the normal range should be.

I'll check where the header passes through the frame again. I did open that up, but maybe it needs a bit more clearance.
 
This is apples to oranges, but my new 1500 mounts from Moss don't budge hardly at all. If I get a 1/4" that's allot. I will say this, I find better quality b/w Moss and VB on mounts.



Hap Waldrop said:
Drew, it could be the header is touching the frame under rpm, you should be able to mock in the garage in neutral while reving. We put steady rods on the race engines for this sort of thing.
Click to expand...


You should also be able to see a tell tale wear mark where it's rubbing.
 
Drew, a peice of masking tape around edge of the hole where the pipe goes through the body. Take and run it then see if messed up the tape.
 
jlaird said:
Drew, a peice of masking tape around edge of the hole where the pipe goes through the body. Take and run it then see if messed up the tape.
Click to expand...
Good idea, Jack. I'll do that.
 
Use the blue stuff. I can't seem to get the new cheap Chinese masking tape glue off if it gets a little warm.
 
I'm with Hap - my header was touching the frame under load, so I installed an engine steady bar. That effectively limited the engine's movement.

Phil
 
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