Engine Valve train noise after cam swap

marcelo

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Feb 25, 2018
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cant see why the longer pushrods ?? orig are 6.248 and you go to 6.400 ..stock heads stock pedestal does not need longer pushrods..?? i did mine 20-22ft lbs but with half turn, TFS Cam, stock length pushrods....
 
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John Dirks Jr

there is enough sticking out to grab on to
Jun 28, 2013
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I question if shims will solve anything. When shims are used on these pedestal type rockers, they reduce lifter preload. If you have a noisy valve train, that suggests not enough lifter preload, usually.

Also, I think if the pushrods were too long, it might not allow the valves to close fully. That would make it difficult to even keep the engine running at all, ot if it did run it would be running very poorly.

Check the rocker arm to spring retainer clearance closely. It's possible for there to be a mismatch in parts compatibility going on.
 

BeesDad

New Member
Apr 29, 2020
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Edmonton
cant see why the longer pushrods ?? orig are 6.248 and you go to 6.400 ..stock heads stock pedestal does not need longer pushrods..?? i did mine 20-22ft lbs but with half turn, TFS Cam, stock length pushrods....

Stock pushrods are definately too short, I tried a couple last night & had a bunch of movement with the rocker bolted down.
 

BeesDad

New Member
Apr 29, 2020
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Edmonton
I question if shims will solve anything. When shims are used on these pedestal type rockers, they reduce lifter preload. If you have a noisy valve train, that suggests not enough lifter preload, usually.

Also, I think if the pushrods were too long, it might not allow the valves to close fully. That would make it difficult to even keep the engine running at all, ot if it did run it would be running very poorly.

Check the rocker arm to spring retainer clearance closely. It's possible for there to be a mismatch in parts compatibility going on.

So I went to try a slightly different procedure last night, turn the rocker bolt until you feel the slightest drag on the pushrod, tighten the bolt until the rocker is seated on the head counting the turn(s) & torque to 20 ft lbs. Cylinder 1 took 3/4 of a turn to seat but when I went to torque it it was already past 20. Cylinder 2 I could barely get it to 1/2 a turn & the bolt was quite tight, past 20 ft lbs I'd say.
 

John Dirks Jr

there is enough sticking out to grab on to
Jun 28, 2013
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So I went to try a slightly different procedure last night, turn the rocker bolt until you feel the slightest drag on the pushrod, tighten the bolt until the rocker is seated on the head counting the turn(s) & torque to 20 ft lbs. Cylinder 1 took 3/4 of a turn to seat but when I went to torque it it was already past 20. Cylinder 2 I could barely get it to 1/2 a turn & the bolt was quite tight, past 20 ft lbs I'd say.

Based on this description you wrote here, it sounds like the pushrod length is in the proper range.

Are you sure once the engine is running that all of the lifters are actually pumping up with oil pressure?

You could check by running the engine with the valve covers removed. Then verify oil dribbling up through the pushrods and across the top of the roc
 

BeesDad

New Member
Apr 29, 2020
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Edmonton
Based on this description you wrote here, it sounds like the pushrod length is in the proper range.

Are you sure once the engine is running that all of the lifters are actually pumping up with oil pressure?

You could check by running the engine with the valve covers removed. Then verify oil dribbling up through the pushrods and across the top of the roc

I haven’t tried that yet but I will tonight. Thank you for the suggestion
 

BeesDad

New Member
Apr 29, 2020
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Edmonton
Based on this description you wrote here, it sounds like the pushrod length is in the proper range.

Are you sure once the engine is running that all of the lifters are actually pumping up with oil pressure?

You could check by running the engine with the valve covers removed. Then verify oil dribbling up through the pushrods and across the top of the roc

Well shims did nothing. I started questioning the lifters & decided to pull off the lower intake & check them out. They all look ok but I noticed that I had roughly 10 out of 16 wrong in the block, the oil holes facing down or towards heads not lifter valley. I have them soaking in oil & will re-install them the correct way & hope for the best. If that doesn’t work I’ll try a match & gasoline as I’m running out of hair to pull out Lol
 

Cheapskate207

The left one hangs a little lower
Jan 12, 2020
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I'm not sure I follow the procedure you did... are you saying that you hit zero lash BEFORE the rocker even touched the head, tightened until the rocker seated, then torqued to 20ft/lbs? The correct procedure is find zero lash then torque to 18-20 ft/lb's, making sure to do so in 1/4 to 1 turn. There is no "seating" the rocker.. unless you do so in the 1/4-1 turn it takes to hit 18-20ft/lbs.
 

BeesDad

New Member
Apr 29, 2020
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Edmonton
I'm not sure I follow the procedure you did... are you saying that you hit zero lash BEFORE the rocker even touched the head, tightened until the rocker seated, then torqued to 20ft/lbs? The correct procedure is find zero lash then torque to 18-20 ft/lb's, making sure to do so in 1/4 to 1 turn. There is no "seating" the rocker.. unless you do so in the 1/4-1 turn it takes to hit 18-20ft/lbs.

Once I get the lifters back in I will use my original method which was get to zero lash & torque them to 20 ft lbs (which I get to in 3/4 of a turn)
 

John Dirks Jr

there is enough sticking out to grab on to
Jun 28, 2013
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cant see why the longer pushrods ?? orig are 6.248 and you go to 6.400 ..stock heads stock pedestal does not need longer pushrods..?? i did mine 20-22ft lbs but with half turn, TFS Cam, stock length pushrods....

I'm not sure the brand of cam that was used but some camshafts have a smaller base circle. Regardless of the valve lift, a cam with a smaller base circle would need longer pushrods, especially if using non adjustable pedestal rockers
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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Mar 2, 2015
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If you installed the lifters upside down you've got bigger problems. Are these roller lifters ?
 

John Dirks Jr

there is enough sticking out to grab on to
Jun 28, 2013
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Doesnt the lifter body have a channel all the way around the circumference where the oil hole is? Thus, don’t they work either way?
 
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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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I guess I've been lucky, never heard about lifter orientation. Never paid it any attention, always put it roller end down, I did keep the lifter, cam lobe matched but I think that may not matter.
 
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