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Posted: Fri Jul 05, 2013 7:39 am
by cva59
No trying to jack this thread but i have a somewhat related question.
Recently my 48 CJ2A lost oil pressure instantly and for no apparent reason. I have since pulled the pan, inspected, found nothing. Distributor turns as expected and the crank appears to be fine.
Yesterday, i pulled the oil pump (dist. still in place). #1 piston is up at TDC. However, the distributor is stuck rock solid in the block and the engine is still in the jeep. I REALLY don't want to pull it at this point.
Is there a trick to install the new oil pump without removing the distributor? I know it would be tricky to do but has anyone ever tried this?
With #1 up, dist. pointed to #1 or as close as possible, could I get the O/P to line up and drop in or am i just wasting my time?
Posted: Fri Jul 05, 2013 8:44 am
by wesk
Since the oil pump gear must rotate about 30 degrees as it slips into contact with the cam it is nigh impossible to complete it's installation without disturbing the distributor. The top end of the oil pump shaft will butt up against the bottom end of the distributor tang before the tang and oil pump slot are aligned. With two people, both reasonably informed mechanical types, and the distributor cap removed it is possible for one troop to press the oil pump to the interference point and then the other troop can manipulate the distributor shaft by rotating slightly until the pump slides the rest of the way up. Then all that is left to do is re-adjust the distributor timing. The oil pump driver must look up into the hole and make sure he clocks the pump driven gear enough to line up with the current distributor tang position after the pump driven gear finishes it's slight rotation.
Posted: Fri Jul 05, 2013 10:55 am
by cva59
wesk wrote:Since the oil pump gear must rotate about 30 degrees as it slips into contact with the cam it is nigh impossible to complete it's installation without disturbing the distributor. The top end of the oil pump shaft will butt up against the bottom end of the distributor tang before the tang and oil pump slot are aligned. With two people, both reasonably informed mechanical types, and the distributor cap removed it is possible for one troop to press the oil pump to the interference point and then the other troop can manipulate the distributor shaft by rotating slightly until the pump slides the rest of the way up. Then all that is left to do is re-adjust the distributor timing. The oil pump driver must look up into the hole and make sure he clocks the pump driven gear enough to line up with the current distributor tang position after the pump driven gear finishes it's slight rotation.
Sounds like quite an undertaking, LOL. I do appreciate the input Wesk. The problem is i cannot budge the distributor for timing or removal. Feels like it's welded to the block and probably is due to the corrosion. It was running and timed right before i removed the OP. If i can get the OP reinstalled with a great deal of luck and everything lined back up, it should be really close i would think but i know my luck and it's mostly all bad on stuff like this. The new pump should be here later next week so i'll repost how this turns out.
Thanks
Posted: Fri Jul 05, 2013 11:07 am
by wesk
How did you determine that the loss of oil pressure was a bad pump? Generally when the pump is the culprit there is a steady decline in oil pressure over a long period. A sudden loss indicates a bearing failure, a stuck open relief valve or a blown out galley plug.
Sooner or later you will need to remove that distributor. With the pump out this is a good time to get the job done right. Warm the block around the distributor shaft with a torch or heat gun. Then rapidly cool the distributor body while tapping the body so as to twist the housing left / right until it breaks loose then start prying or pulling up after each heat and cool cycle.
The procedure I described works with a stuck distributor. Just mark the rotor tip position on the distributor housing and proceed as I mentioned above. If after seating the oil pump the rotor position doesn't match the mark then back the pump out and clock it one more tooth in the needed direction and re-insert it.
Posted: Fri Jul 05, 2013 11:20 am
by cva59
wesk wrote:How did you determine that the loss of oil pressure was a bad pump? Generally when the pump is the culprit there is a steady decline in oil pressure over a long period. A sudden loss indicates a bearing failure, a stuck open relief valve or a blown out galley plug.
Sooner or later you will need to remove that distributor. With the pump out this is a good time to get the job done right. Warm the block around the distributor shaft with a torch or heat gun. Then rapidly cool the distributor body while tapping the body so as to twist the housing left / right until it breaks loose then start prying or pulling up after each heat and cool cycle.
The procedure I described works with a stuck distributor. Just mark the rotor tip position on the distributor housing and proceed as I mentioned above. If after seating the oil pump the rotor position doesn't match the mark then back the pump out and clock it one more tooth in the needed direction and re-insert it.
I just assumed with no oil pressure it must be the OP. I pulled the pan looking for shavings and such, nothing. The dirty oil was clean from anything like that. The 3-4 prior runs it had a strong 40 psi then on the last run it had no OP from the starting of the engine. Gauge stayed on 0 and started rattling so i killed it. That's where i am now. The pan is off and the pump is out and i'm getting more and more discouraged by the minute.
Posted: Fri Jul 05, 2013 11:32 am
by wesk
Was the oil pickup screen clean?
Is the oil pickup screen tube fit tightly into the block?
Posted: Fri Jul 05, 2013 11:51 am
by cva59
wesk wrote:Was the oil pickup screen clean?
Is the oil pickup screen tube fit tightly into the block?
Yes, the screen is very clean. I did notice the screen part rotates up and down like a float. Is that correct? The tube and all is tight and solid.
http://i537.photobucket.com/albums/ff33 ... f8.jpg[img]
http://i537.photobucket.com/albums/ff33 ... 2ea86d.jpg[/img]
Posted: Fri Jul 05, 2013 1:13 pm
by wesk
Looks fine.
Posted: Fri Jul 05, 2013 2:05 pm
by RICKG
I probably shouldn't jump in here, but at
this point are you sure you've got a working
OP gage and sender?
Posted: Fri Jul 05, 2013 2:09 pm
by wesk
Rick, You missed the comment on the rattling of the mechanicals when the oil pressure went zero? Eh!

Posted: Fri Jul 05, 2013 3:39 pm
by RICKG
cva59 wrote:[Gauge stayed on 0 and started rattling so i killed it.
I guess I thought he meant the gage was rattling but in retrospect
I spose that don't make much sense does it..

Posted: Mon Jul 08, 2013 8:22 am
by cva59
I sure wish a simple gauge problem would have been the fix. I'm sure gonna hate to put this thing back together and still no OP dur to something like you pointed out Wesk:
"A sudden loss indicates a bearing failure, a stuck open relief valve or a blown out galley plug"
I will be moving it to my dad's shop pretty soon. I will have a much better place to work on it in the A/C so until this happens in a couple weeks i won't really know much more.
I will definietly keep you all posted becuase i'm sure i will be needing more help.
Thanks
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Posted: Sat Jul 13, 2013 2:06 pm
by cva59
Well, i reinstalled the original pump since it appears to be working, installed the oil pan, blew out the oil filter lines with air, installed a new gauge right into the block fitting and still no oil pressure.
I have to say i am about done with this dude! My patience is gone and i cannot afford an engine rebuild nor do i wish to get into that.
So, if anyone has any ideas that are easy to try please let me know before i stick a for sale sign on this thing.
Thanks
Posted: Sat Jul 13, 2013 6:13 pm
by wesk
Did you prime the pump?
Posted: Sat Jul 13, 2013 7:38 pm
by cva59
wesk wrote:Did you prime the pump?
no, what's the process for that? Same as a SBC?