GordnadoCRD wrote:
Curiosity piqued!
I wonder, amongst all the dropped valves we've had, how many could have started this way?
Yup I really wonder this too, lose one keeper and then its just a matter of time before it drops and BAM. Out of curiosity last night I looked at the head I have with a dropped valve, turns out only one keeper was in it......hard to say when it was lost though.
Mountainman wrote:
You should buy a lottery ticket! Well, hopefully the other end is intact. I've seen them bend the stem and jam it in that position.
I opened one that the valve was completely free, and it hurt nothing! Only thing I could figure was that it dropped in after the engine was shut down. Didn't even bend the valve.
I did a leak down test which shows 99psi out of 100psi, so I think the valve to seat is good as well as rings. I then "popped" each valve with a smaller rubber hammer to verify they opened and vented good. I'd say at this point I'm confident its not bent and is useable on the seat side, I just need to check the keeper rings in the end of the valve, if they rings were not damaged and will hold a keeper correct I think I'm good to go.
WWDiesel wrote:
To add; I have seen a lot of destroyed engines over some 40+ years and I don't ever remember seeing one that half a keeper was missing.
Sam did not say he found the other half did he?
Wonder if someone actually assembled the head in this manner?
In the machine shop, we always would strike the valve head with a hammer a couple of times to make sure the keepers were fully set and tight.
I have seen 100's of broke valves where the stem broke over the years, but the spring and keepers always remained in intact.
We floated valves all the time in drag race engines and never had valve keepers come out! Usually a rod or piston always gave up first.
I suppose that possible, I can tell the wiring harness was removed at some point over the engine, the fuel return lines at the top of the injectors have a JB welded nipple where it connects to that fuel return junction, and the injectors were super clean looking of gunk.
That said I don't see any evidence the intake had been off before, and I do see evidence the EGR was worked on or replaced, maybe someone pulled all that crap just to work on EGR?
I also cannot image it was installed bad, and lasted long enough for these rockers to fail so badly, this is 100k+ miles of rocker bearing wear, its hard to imagine the keeper held on that long.
I think its more likely just a weird way the rocker failure let a keeper pop out.
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