LPO Issue?

psduser1 · Aug 7, 2017

ToMang07 said:
Oil (pressure) comes up through the pushrods doesn't it?

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The rocker is damaged from lack of oil, mostly.
Lack of oil (pressure) is caused by loose bearings, and possibly, poor pump performance.
Lifters have zero to do with oil pressure, under normal operating conditions. All the oil in the top end-hpop aside-is basically splash lubrication. Assuming you don't have a collapsed lifter of course.
If you had a pump failure, this could just be the delayed end results.

opcorn:

ToMang07 · Aug 7, 2017

You don't think a little bleed off from the lifters could cause it? I mean it makes sense to me.

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ToMang07 · Aug 7, 2017

Really I'm more worried about what happened to the cylinder from the engine running with no intake or exhaust opening.

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Magnum PD · Aug 7, 2017

You could check compression or put a bore scope in it

psduser1 · Aug 8, 2017

ToMang07 said:
You don't think a little bleed off from the lifters could cause it? I mean it makes sense to me.

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Define a little. The lifter should bleed some oil,that is how the rocker is lubricated.

ToMang07 said:
Really I'm more worried about what happened to the cylinder from the engine running with no intake or exhaust opening.

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As magnum suggested. How long did the engine run with a dead cylinder?

ToMang07 · Aug 8, 2017

Magnum PD said:
You could check compression or put a bore scope in it

I'll have to buy or rent one today.

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ToMang07 · Aug 8, 2017

psduser1 said:
Define a little. The lifter should bleed some oil,that is how the rocker is lubricated.

As magnum suggested. How long did the engine run with a dead cylinder?

Well, it's only 1-2 psi below spec LPO.

It ran roughly 60 miles, maybe a little more. I thought it was a dead injector/harness, so like a dumb ***k I wasn't as worried about it and it basically has been sitting since March.

I have a compression tester, but I can't get the damn thing on the adapter. It won't fit and the local auto parts stores basically just have the same kit/style I have.

It has some compression.

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ToMang07 · Aug 8, 2017

Looking around, I can't find a reasonably priced borescope with a tip small enough to work.

psduser1 · Aug 8, 2017

If you can't get a borescope, a compression test on that bank-the other three for a reference-should give you a pretty good idea of the cylinder condition.
If nothing else, put it together and run it for a bit, see how it runs. Not ideal, but without fire in that cylinder, you might be surprise at the level of damage done (or not done).
The other option is to pull the head, but that would be the last resort, imo.

ToMang07 · Aug 8, 2017

psduser1 said:
If you can't get a borescope, a compression test on that bank-the other three for a reference-should give you a pretty good idea of the cylinder condition.
If nothing else, put it together and run it for a bit, see how it runs. Not ideal, but without fire in that cylinder, you might be surprise at the level of damage done (or not done).
The other option is to pull the head, but that would be the last resort, imo.

Yeah, if it's that bad I'll find another runner and replace it. Right now I'm debating pulling the injector to scope it. I'd rather not tho. Waiting on the rockers from Riffraff and a different compression tester to come in.

How much difference is there testing compression cold vs hot?

I will say there wasn't much blow-by last time I ran it, however it has an atmosphere vent.

ToMang07 · Aug 8, 2017

I'm trying to guess/figure out what could have caused both rockers to snap. All evidence I have found indicates valve float. Problem is I have shimmed 910s and with a stock injectors/turbo that is very unlikely. The fact that the pushrods are straight just compounds this issue for me, I'd thing they would bend BEFORE the rockers snapped.

I appreciate all advice, feedback. Thanks as always, fellas.

psduser1 · Aug 8, 2017

I can't answer that question,lol. Some guys-lincolnlocker- will flat tell you they over-revved a few times, with very few issues.
Other guys will never admit to over-revving the engine, and break all sort of stuff.:wtf:
910s, even shimmer, aren't the answer for a rowdy street setup, really, but they should be enough for a dd.
I assume most compression tests are run on a cold engine, just cause no wrench I've met likes working on hot engines, lol.

Magnum PD · Aug 8, 2017

I got a bore scope I can ship ya.

Let me try it on my rig and see if goes in the glowplug hole.

Magnum PD · Aug 8, 2017

It doesn't go through glowplug hole but, it'll go through the injector hole. It's not a high resolution one but if you could shine a light down the glowplug hole that'll help you see better. It has lights on the end of it but not a real bright one.

ToMang07 · Aug 9, 2017

Magnum PD said:
I got a bore scope I can ship ya.

Let me try it on my rig and see if goes in the glowplug hole.

Magnum PD said:
It doesn't go through glowplug hole but, it'll go through the injector hole. It's not a high resolution one but if you could shine a light down the glowplug hole that'll help you see better. It has lights on the end of it but not a real bright one.

I might take you up on that, the soon as I get a compression reading that's my next step depending on compression. Honestly if it's above 300psi I'll be amazed.....but happy. Not getting my hopes up tho.

Magnum PD · Aug 9, 2017

"I" don't think it caused that much damage but you can look for valve contact.

ToMang07 · Aug 10, 2017

Well, I think the cam is gone, seeing as there is NO lift on the outtermost rocker.

http://www.youtube.com/watch?v=RD3Kdhj-IWU

http://www.youtube.com/watch?v=6h-Ixfz15fE

Magnum PD · Aug 10, 2017

Damnit. Maybe it's a bad lifter?

That was from the broken rockers right?

ToMang07 · Aug 10, 2017

Magnum PD said:
Damnit. Maybe it's a bad lifter?

That was from the broken rockers right?

I still can't figure out how both broke. The other one works fine, but the (intake?) front-most rocker wont budge. Dropped some fresh oil down the hole too and started the motor, nothing, you can almost feel the cam hitting the lifter tho when you touch it.

Also, I noticed it feels like I'm not getting any compression now, either. Not sure if that's because the other valve is opening or not, but I felt no air through the compression fitting next to the dead rocker.