Engine guys help! No oil pressure!
Thread Starter
Safety Car
Joined: Oct 2000
Posts: 4,282
Likes: 172
From: Lake Wylie, South Carolina
Engine guys help! No oil pressure!
Well "Bad Luck Rat" is back!!! Most of you know the strange issues that I have had since starting this project. Well here is another one. I was getting the dash put back together after installing a fan overide switch and lights for the fans. After reinstalling everything I cranked the car for the first time in about 3 weeks. After getting it to idle I look down and the electric oil pressure guage reads 0!!!! I quickly turned the car off. Since it is an electric guage the first thing I thought was that I pulled a terminal off the guage. No Luck!! Everything was hooked up as it should be. I then went and bought a manual oil pressure guage and installed it. I pulled the distributor and used an old distributor shaft on a drill to spin the pump. I spun the pump for probably 3-5 minutes and oil never appeared in the plastic oil line and the manual guage never moved.
I have already pulled the pan and the pump. Is there a way to check the pump? Is there something that I am missing? If I really had 0 oil pressure did I do any damage in the brief run time?
The pump is a GM L88 pump and the motor has 500 miles on it at the most.
I have already pulled the pan and the pump. Is there a way to check the pump? Is there something that I am missing? If I really had 0 oil pressure did I do any damage in the brief run time?
The pump is a GM L88 pump and the motor has 500 miles on it at the most.
Intermediate
Joined: Oct 2009
Posts: 37
Likes: 0
From: West Michigan
Where did you connect the manual pressure gauge at? Nothing else has changed to the engine since you shut it off three weeks ago? The new pump could have failed, but I think it might be something simple. Try the gauge on the top end oil tap behind where the distributor is located and try your drill and old distributor prime again.
Thread Starter
Safety Car
Joined: Oct 2000
Posts: 4,282
Likes: 172
From: Lake Wylie, South Carolina
Where did you connect the manual pressure gauge at? Nothing else has changed to the engine since you shut it off three weeks ago? The new pump could have failed, but I think it might be something simple. Try the gauge on the top end oil tap behind where the distributor is located and try your drill and old distributor prime again.
Thanks
Wade
Melting Slicks
Joined: Mar 2009
Posts: 3,126
Likes: 15
The chances of the pump failing are slim. If pump is still off, place pick up into pan with oil. Turn shaft clockwise, by hand, oil should rise out of pump outlet. I am thinking with all those stars after your user id you have already done this. mds...
Intermediate
Joined: Oct 2009
Posts: 37
Likes: 0
From: West Michigan
I agree the chance of the oil pump failing are slim, but if you have it all apart, you can try another pump. With the electric sender, they go bad, and your idea of the manual gauge is correct, but I would try to tap into the oil system some where else. Also the coupler could have come off on the oil shaft (again not likely), but look before reassembling. You just never know.
Thread Starter
Safety Car
Joined: Oct 2000
Posts: 4,282
Likes: 172
From: Lake Wylie, South Carolina
Sould I pull the main caps one at a time and check the bearings? Is my mechanical guage mounted in an area where it would take a very long time for it to register any pressure. I would say clogged oil filter but it is fairly new and all the breakin oil was changed long ago.
Melting Slicks
Joined: Mar 2009
Posts: 3,126
Likes: 15
OK, here is what I know. Oil pump has a pressure relief valve, spring and drift pin that holds it in. Is that in place? Stopped up filter is rare. Filter has a by pass that will let oil flow even if filter is plugged. Do not remove main or rod caps at this time. Did engine make any knocking sounds from valve train? If not that is a good sign. Did pump pick up oil when you turn by hand with pick up submerged in oil? I am sure some of the engine guys will tell us what is going on. Good luck, mds...
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Thread Starter
Safety Car
Joined: Oct 2000
Posts: 4,282
Likes: 172
From: Lake Wylie, South Carolina
OK, here is what I know. Oil pump has a pressure relief valve, spring and drift pin that holds it in. Is that in place? Stopped up filter is rare. Filter has a by pass that will let oil flow even if filter is plugged. Do not remove main or rod caps at this time. Did engine make any knocking sounds from valve train? If not that is a good sign. Did pump pick up oil when you turn by hand with pick up submerged in oil? I am sure some of the engine guys will tell us what is going on. Good luck, mds...
Melting Slicks
Joined: Mar 2009
Posts: 3,126
Likes: 15
I have seen it take a few minutes of running time with hot oil to fill the semi clear line you are talking about. Since it is a closed tube the air has no place to go but will eventually be displaced by oil. Again, good luck. I will be watching your progress. mds...
Melting Slicks
Joined: Feb 2003
Posts: 3,053
Likes: 4
St. Jude Donor '03,'11
I wish you would have waited to pull the pan off. You could have simply popped a valve cover off and looked for oil out the rockers.
If you had no oil pressure the engine would have been clicking like hell (hydraulic lifters) while you were warming it up. How long did you run it?
Thread Starter
Safety Car
Joined: Oct 2000
Posts: 4,282
Likes: 172
From: Lake Wylie, South Carolina
Why would it? The gauge is some sort of sealed bulb. How is the oil going to get there. The oil is pushing on the air in the tube to work the guage.
I wish you would have waited to pull the pan off. You could have simply popped a valve cover off and looked for oil out the rockers.
If you had no oil pressure the engine would have been clicking like hell (hydraulic lifters) while you were warming it up. How long did you run it?
I wish you would have waited to pull the pan off. You could have simply popped a valve cover off and looked for oil out the rockers.
If you had no oil pressure the engine would have been clicking like hell (hydraulic lifters) while you were warming it up. How long did you run it?
Melting Slicks
Joined: Feb 2003
Posts: 3,053
Likes: 4
St. Jude Donor '03,'11
Even if you had no pressure and i think you did, that much time won't hurt anything. Hell everytime you start up there's no pressure for a few seconds. Start adding up hundreds of starts and you're at a few minutes. Yea, you put a little wear on it but nothing devistating.
Thread Starter
Safety Car
Joined: Oct 2000
Posts: 4,282
Likes: 172
From: Lake Wylie, South Carolina
Is it possible that while I was doing the electrical work on the switch and lights for my fans that I shorted out the OP sending unit? Do the sending units sgort out? The guage itself moves to zero when the switch is turned on just like all the other guages.
Intermediate
Joined: Oct 2009
Posts: 37
Likes: 0
From: West Michigan
I agree with Turtlevette, you probably have oil pressure. The sending unit is normally the problem, that is why you should try to get a reading from another spot on the block. I am confident that you did not cause any or very little damage. You are wise to use a manual gauge to test for pressure. I had the problem before as you are now. I just hooked up the manual gauge and had someone start the engine and within a couple of seconds, the gauge shot right up. I had to change the sender. After that everything was good.
Burning Brakes
Joined: Dec 2008
Posts: 971
Likes: 45
From: Middlesex NJ
If you wana see oil in that hose.... take it off the gauge and then use the drill on the pump. Air trapped in the line will act like a shock absorber as air compresses and fluid does not.
Just have someone hold the end of the mechanical gauge line (tube) into a gallon milk jug or something while priming.
I agree that you would see oil on the rockers when first time priming in a minute or so depends on speed of drill.
I don't think I saw much pressure on my mechanical with a drill due to air in the line .
Just have someone hold the end of the mechanical gauge line (tube) into a gallon milk jug or something while priming.
I agree that you would see oil on the rockers when first time priming in a minute or so depends on speed of drill.
I don't think I saw much pressure on my mechanical with a drill due to air in the line .
