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Flat tapet lifter spinning rapidly

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I have a '65 Chrysler 300 with a 383. Yesterday I changed out the valve seals with the heads still on the engine. When I started the engine up with the valve covers off I noticed three of the pushrods/lifters rotating at a fast pace. I pulled these lifters and didn't see any unusual wear pattern on the bottom of the lifter or the cam lobe.
Has anyone seen this before or any ideas as to what would cause this?
My guess is weak valve springs.
 
I don't know how fast their supposed to spin? I'd be more worried if they weren't spinnin.
 
I have a '65 Chrysler 300 with a 383. Yesterday I changed out the valve seals with the heads still on the engine. When I started the engine up with the valve covers off I noticed three of the pushrods/lifters rotating at a fast pace. I pulled these lifters and didn't see any unusual wear pattern on the bottom of the lifter or the cam lobe.
Has anyone seen this before or any ideas as to what would cause this?
My guess is weak valve springs.
I have had my covers off with the engine running and have seen the push rods spinning. It is normal and they will spin at different speeds based on how fast the lifter is spinning on the cam lobe and the harmonic frequencies of the engine. I bet the other ones are spinning as well, just much slower.
 
Well they should all spin at the same speed. And I would think that should be as fast as the fast one(s).
 
I noticed this when building my motor, some do spin faster. As long as they all spin, that is what matters.
 
Ur valve spring idea could very well be right after that many yrs/ miles. If they all rotate I wouldn't worry too much.
 
The three in question are spinning at about 450rpm at idle. Never saw them turn that fast before.
 
RPM gun! As a kid my dad owned a hydraulic shop and had an RPM gun in the tool kit. My favorite thing to do was take that gun, put the reflective tape on stuff and then spin it or see what RPM it was going.
 
I'm really curious as to how you were able to measure the rotational speed of the lifters that accurately?

Thinking more about this, you say the lifters are rotating at 450 RPM at idle. Engine idle speed should be around 800 RPM (Crankshaft). That means your camshaft rpm is 1/2 that speed, or 400 RPM at idle. So, that now means that you have 3 lifters that are making more than 1 FULL revolution for every bump of the camshaft lobe.

As Artie Johnson of Laugh In fame would say, "VERY Interesting".
 
If you wanted to get real technical. We would have to measure the diameter of the lifter (wear patern)that rides on the the edge of the cam lobe and would also have to factor in the cicumferance of the cam lobe to calculate the ratio. Which I hardly think that would be the same speed of the cam.
Now I'm even more confused!
 
Maybe individual cam lobe wear ? Not seen by eye ?
 
Thinking more about this, you say the lifters are rotating at 450 RPM at idle. Engine idle speed should be around 800 RPM (Crankshaft). That means your camshaft rpm is 1/2 that speed, or 400 RPM at idle. So, that now means that you have 3 lifters that are making more than 1 FULL revolution for every bump of the camshaft lobe.

As Artie Johnson of Laugh In fame would say, "VERY Interesting".
Very interesting is right. The more I think about it, it almost doesn't even sound possible.
 
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