oil pump failed

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like_A_pike

like_A_pike

that's not factory
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long blocked and sleeved 340. Everything new but the valve train. Primed the new pump and got oil up top before buttoning it up and installing the motor. Started right up and sounded good. While working on getting up to temperature, I noticed the top end was kinda loud and then noticed zero oil pressure on the gauge. Shut it off and changed the gauge and started it again, still nothing but it would go to 10psi at 2000 rpm. Shut it down and checked that all the gallery plugs had been replaced and then put heavier oil in it. noticed some very fine metallic looking crud stuck to the oil pan plug. No chunks in the filter though. Still no pressure. Took the intermediate shaft out and tried to prime it again. When I noticed the bit wouldn't engage anything down there. So something is buggered up in there and the motor is coming back out.

My question to you all is; what can I do, shy of a tear down, to see if I've damaged anything else in the motor? The sum of run time was nearly ten minutes.

thanks
 
You have to pull the pan to replace the pump so what is the problem inspecting? Pull a couple of main caps and see what you see

I would not be so quick to blame the pump. Maybe it's the intermediate shaft..........................
 
Oil pumps VERY and I mean VERY rarely fail "all by their self". I would be looking for a piece of "something" in the pump that locked it up. Trash that's gotten wedged into a main oil galley, or something "like that". Did you ever see GOOD oil pressure on the gauge? If not, remove the distributor and check to make sure the pipe plug is installed in the block in the main oil galley on the driver's side. If that's left out, you'll get very little to no oil pressure.
 
What does the hex end of the intermediate shaft look like? I'm assuming it didn't break off, or, you wouldn't have had 10 PSI at 2000 RPM. If it truly ran 10 minutes without oil pressure better than that, I'd be pulling the pan and bearing caps......all of them. Disassemble the pump also and checked pressure relief valve to see if it's stuck wide open.
 
RustyRatRod said:
Oil pumps VERY and I mean VERY rarely fail "all by their self". I would be looking for a piece of "something" in the pump that locked it up. Trash that's gotten wedged into a main oil galley, or something "like that". Did you ever see GOOD oil pressure on the gauge? If not, remove the distributor and check to make sure the pipe plug is installed in the block in the main oil galley on the driver's side. If that's left out, you'll get very little to no oil pressure.
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I'm thinking the end of the hex did not line up when they put the gear in the oil pump and it jammed and broke...
 
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like_A_pike said:
long blocked and sleeved 340. Everything new but the valve train. Primed the new pump and got oil up top before buttoning it up and installing the motor. Started right up and sounded good. While working on getting up to temperature, I noticed the top end was kinda loud and then noticed zero oil pressure on the gauge. Shut it off and changed the gauge and started it again, still nothing but it would go to 10psi at 2000 rpm. Shut it down and checked that all the gallery plugs had been replaced and then put heavier oil in it. noticed some very fine metallic looking crud stuck to the oil pan plug. No chunks in the filter though. Still no pressure. Took the intermediate shaft out and tried to prime it again. When I noticed the bit wouldn't engage anything down there. So something is buggered up in there and the motor is coming back out.

My question to you all is; what can I do, shy of a tear down, to see if I've damaged anything else in the motor? The sum of run time was nearly ten minutes.

thanks
Click to expand...


You're gonna have to drop the oil pan to get to the oil pump anyway... Check for debris in the pan and see what it looks like...

Clean any debris out of the engine and then maybe pull a rod cap or two and see what they look like... Then do a main cap or two...

Then make sure all debris is cleaned up and fix the oil pump and put it together...
 
I tried to reinsert the hex bit on my drill and it doesn't engage anything down there. there is no wear on the intermediate shaft. It seems like it was just riding over the destroyed receiver in the pump. I'll definitely be inspecting anything on the bottom but I am assuming a tear down is everything up top too.
 
would anyone do a compression test after checking/cleaning up the bottom to see if anything is appreciably different up there?
 
Along with "everything else" I'd be checking the length of the intermediate shaft. Are you sure the dist. was fully seated? Maybe the intermediate shaft bushing was not fully seated
 
I kinda doubt it would all go together if the shaft wasn't down all the way, Not a lot of extra clearance for stuff sticking up far enough for the shaft not engaging the pump.
 
Sounds to me that the input hex in the pump is stripped, or the pressure relief valve is stuck open. If he had oil pressure to begin with, and can get 10 PSI out of it at 2000 RPM, the shaft didn't break, and the oil gallery plug must have been in there. I guess it could fail, or some other oiling oddball failure (not bearing or pump related), but, that would be pretty rare.
 
You won't know the answer until you tear into it. That much is certain.
 
cudamark said:
I kinda doubt it would all go together if the shaft wasn't down all the way, Not a lot of extra clearance for stuff sticking up far enough for the shaft not engaging the pump.
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I've had the shaft jam in the pump and break the pump before... I always put the shaft in first, then the oil pump on the hex for the shaft so I know that it's properly lined up and doesn't jam and break...
 
RustyRatRod said:
You won't know the answer until you tear into it. That much is certain.
Click to expand...


I do know the answer from my crystal ball, but I'm not going to tell...

I'm gonna let it be a surprise...


crystal-ball.jpg
 
like_A_pike said:
I tried to reinsert the hex bit on my drill and it doesn't engage anything down there. there is no wear on the intermediate shaft. It seems like it was just riding over the destroyed receiver in the pump. I'll definitely be inspecting anything on the bottom but I am assuming a tear down is everything up top too.
Click to expand...


I wouldn't tear the whole thing apart yet...

See what kind of debris is in the pan and bottom end and go from there... If there's alot, then you're gonna have to tear into it further... If there is not alot of debris and damage and it's easy to clean out, then clean it up and get everything back together again...
 
Be interesting to see what this ends up being.

You know...... for those of us without the crystal ball....... or know how to read tarot cards.
 
PRH said:
Be interesting to see what this ends up being.

You know...... for those of us without the crystal ball....... or know how to read tarot cards.
Click to expand...

I went to the local palm reader this mornin but all she wanted to do was get in my pants.
 
Its possible you had 30 ish when the engine was cold. I have never seen a small block take out a pump like that and you still had 10psi. I bought a 340 dart with a new 340 that had no oil pressure and needed to be re-rebuilt but it was missing the galley plug in front if the distributor gear but you mentioned you checked for that I think. it always had 10-15 psi hot and 60 when fixed. Good luck and I am interested to see what you find.
 
If it was mine and there was metal in the pan/oil I'd take it completely apart and clean and inspect everything.
 
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