How many of you have seen this before (Bone stock)

YOUNG GUNS15

YOUNG GUNS15

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Finally got the chance to figure out why my new to me 1997 215hp engine has a miss. Pulled the rear valve cover off and found the intake valve had pulled through the retainer. Okay no big deal I have keepers and a retainer so I swapped them on. I decided it would be a good idea I check the rest, and every single one has pulled through! This is a bone stock 150k mile engine.

So how many of you have seen this on a completely stock engine? I know it happens on high rpm applications but this seems out of place to me. Only thing I can figure is someone downshifted way to far.

Edited because I hit the send button too early

-Spence
 
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Had a Samsung Escavator with rougly 1500hrs on its 5.9 where the retainer failed and it dropped the entire valve through the piston and broke through the cyl wall. Im sticking with made on friday parts. May just be the quality of steel used too. Hard to really say.

Get your shaft yet??
 
Ive decided I have some crazy luck in a good way. The first one I changed looked like it was ready to bomb out the cylinder!

Nope should be here tomorrow! Then I get to dig into my transmission... Uhg
 
A neglected truck that has not had the lash adjusted properly can get the lash so loose it beats on the valve stems. I suppose with 150K miles and never being adjusted, the lash could have been loose enough to beat the locks through the retainers.

Not saying that's the case on this truck, just saying it's possible.
 
Big Blue24 said:
A neglected truck that has not had the lash adjusted properly can get the lash so loose it beats on the valve stems. I suppose with 150K miles and never being adjusted, the lash could have been loose enough to beat the locks through the retainers.

Not saying that's the case on this truck, just saying it's possible.
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I have no idea what the previous owner has done to this motor. It has been out of the truck for a while. I'm just fixing it up to sell locally. I think it's odd a completely stock engine would do this. Figured I'd see who else has encountered this. 150k miles is not a lot at all.
 
How far did the valve push through? Did you check the pistons?

Sent from my DROID3 using Tapatalk 2
 
madmikeismad said:
How far did the valve push through? Did you check the pistons?

Sent from my DROID3 using Tapatalk 2
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The pistons will be okay. It's a bent valve I'm worried about. Hopefully it took out a pushrods instead of a valve. Mechanical fuse...

This was by far the worst one. It's next to a repaired valve for comparison.

aee887cc-9333-7b13.jpg
 
It happened on my 98 12v too. 4k rpm's and street driving was hard on the stockers.
 
New/used keepers and retainers swapped in. Stay tuned for engine stand testing videos tomorrow. Let's see if the miss is fixed :)
 
Olee Poole said:
Was the push rod OK in that CLY?
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I looked at them both and they looked straight. Couldn't fix the miss with a valve adjustment, or swapped injector so it's being parted. Most likely a bent valve, the cylinder hasn't seen combustion for a Long time. piston is almost clean of any carbon..

I have video of it running on the stand but I can't get the vid to upload from my phone
 
You still have the head on it? Pull the injector out.. back off on both rockers and put shop air in that cly with a rubber tip blow gun.

You will know if and which valve is bent.
 
Olee Poole said:
You still have the head on it? Pull the injector out.. back off on both rockers and put shop air in that cly with a rubber tip blow gun.

You will know if and which valve is bent.
Click to expand...

Already yanked it apart. The markings FRONT and STD are stamped in the valves and every piston has contact. Sucks lol
 
Is the cylinder head a china version or cummins? Maybe the valves, keepers & retainers were replaced at one time...with aftermarket parts???
 
Valve lash was allowed to get way out of spec. Hammered the valves through the retainers. I see it all the time on neglected gen-sets. The natural gas or propane ones seem more prone to this happening.
 
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