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comp lifters

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matty 401 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote matty 401 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/13/2017 at 8:19am
no answer from Comp  so looks like i am on my own 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Slate Quote  Post ReplyReply Direct Link To This Post Posted: Dec/13/2017 at 9:36am
It would benefit you to follow-up on the advice of an experienced engine builder - sure you could have gotten a bad set of lifters but the failures you describe are an extreme form of failure.

Steve
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SC397 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SC397 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/13/2017 at 2:06pm
Originally posted by 6PakBee 6PakBee wrote:

Looks something like this?






I have had a failure like that with Comp lifters but it wasn't the lifter's fault. The failure was a fuel pump arm breaking off and jambing in to the timing set breaking the timing chain... while running at 2500 rpm. The shock load of the valves hitting various pistons etc was too much for the lifters. I had several that cracked and a few with the bottoms broke off. I will see if i can find the pictures.
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matty 401 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote matty 401 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/13/2017 at 3:07pm
i did have the timing off  and was bumping it over with the starter and bent all 8 exhaust valves  but never did it fire and run  just turned over with starter  no pushrods bent either 
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SC397 View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote SC397 Quote  Post ReplyReply Direct Link To This Post Posted: Dec/14/2017 at 6:47am
I didn't bend any push rods either.
I wouldn't have even considered going to Comp for reinbursement after a issue like that. If you bent valves, all bets are off.

Edited by SC397 - Dec/14/2017 at 6:54am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote sweatlock Quote  Post ReplyReply Direct Link To This Post Posted: Dec/14/2017 at 5:03pm
Originally posted by matty 401 matty 401 wrote:

i did have the timing off  and was bumping it over with the starter and bent all 8 exhaust valves  but never did it fire and run  just turned over with starter  no pushrods bent either 


A crucial piece of information
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billd View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote billd Quote  Post ReplyReply Direct Link To This Post Posted: Dec/14/2017 at 5:24pm
Doesn't matter if it fired or not - I've seen slipped timing chains bend and break things just during cranking, and I've seen things bent to heck just during cranking. My old tractor was an example - simple CRANKING it after it sat a few years and the valves stuck bent and twisted rocker arms! (oddly, only one or two push rods were bent)
Push rods are strong steel tubes with the force ideally pushed directly end-to-end......... they won't always bend even if you break other things. 
There's a whole lot of torque involved just with a starter.
My best guess is that there's not a problem with defective lifters - for one thing, what sort of a defect would BREAK them?
This sounds more and more like a physical engine issue rather than defective parts. 

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Post Options Post Options   Thanks (0) Thanks(0)   Quote billd Quote  Post ReplyReply Direct Link To This Post Posted: Dec/14/2017 at 5:26pm
Originally posted by SC397 SC397 wrote:

I didn't bend any push rods either.
I wouldn't have even considered going to Comp for reinbursement after a issue like that. If you bent valves, all bets are off.

Yup - this isn't a defective part so much as a physical issue with the re-assembled engine. Knowing the forces, etc. - I never really considered this a defect in parts so much as "ok, what went wrong" situation.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote amcglass Quote  Post ReplyReply Direct Link To This Post Posted: Dec/14/2017 at 6:09pm
just this past summer I had a set of Comp lifters fail me after 20 minutes of run time on a Brand new motor   
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Post Options Post Options   Thanks (0) Thanks(0)   Quote purple72Gremlin Quote  Post ReplyReply Direct Link To This Post Posted: Dec/14/2017 at 7:38pm
If I wasn't sure...I'd use a breaker bar and turn the engine by hand.....if it stops... check it...
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