Oil pump housing

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b74eqcm
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Joined: Sat Sep 26, 2015 6:35 pm
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Re: Oil pump housing

Post by b74eqcm »

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I thought solid 20 psi with a cordless drill motor was pretty good. In any case going from 20 on the bench to zero is a big jump.
Measuring with the gauge that is tied into the pressure switch. My indicator light also came on.
[/quote]

This makes me wonder: Is the oil pressure gauge electric? And was the engine properly grounded? It's possible an ungrounded engine would indicate 0 psi on an ungrounded gauge.
Jim Thomas
Bethel, VT
63 Monza Coupe
66vairguy
Posts: 4531
Joined: Tue Dec 21, 2010 3:44 pm

Re: Oil pump housing

Post by 66vairguy »

Zero PSI is an indication of a major failure. I always use a mechanical gauge. You can use a fitting at the oil pressure switch, or use the adapter Clark's sells that replaces the oil filter bolt. I like to make sure oil is flowing to the filter and it's easier to remove when you're done (after break-in of an hour or so I replace the filter and oil and look for debris or metal grit in oil).

Not being a character, but more one than one person has started a new engine with no, or low oil, in the pan. I assume you've checked the oil level. Sometimes dipsticks aren't accurate, or the wrong one. I count the quarts I put in and then look at the oil level on the dip stick. After I prime the engine (fill the new oil filter) I check again to verify an oil level drop and the appropriate level on the dip stick.

If the oil level is good, then either the gear sheared on the shaft, shaft broke, etc. If the engine was running then the gear turning the distributor shaft must have been intact. The other possibility is the oil pan pickup went dry - If you have a deep oil pan you should be using a lower point pickup, stock will be too shallow. Once I had an oil pickup tube that was partly crushed due to someone lifting the engine via the oil pan. Hard to spot until you remove and inspect the oil pan pickup.

One thing at a time -
Check oil level.
Pull the distributor and inspect the shaft were it goes into the oil pump gear shaft slot. If shaft is good - put in something to carefully (don't damage hole in the housing) turn the oil pump gears. You should feel them turn. If something feels odd you have to dismantle the pump and inspect the gears/shaft. Some gears have a pressed/splined shaft, some use a pin.
Pull the oil pan and inspect the oil pan pickup.


Good luck.
gnrand
Posts: 277
Joined: Sun Nov 15, 2015 8:10 am
Location: Wildomar,Ca

Re: Oil pump housing

Post by gnrand »

I to thought of the oil level and over filled it but still low pressure. Actually the gauge read approx. 2 psi when the engine started. I pulled the oil pump housing and found that there was no spring in the pressure relief valve. Interesting because I was told it was ready to go. I am slowly putting it all back together and should be able to test it as soon as I get more oil and a filter. I am pretty upset right now having gone through all the disassembly and reassembly. I have everything removed to pull the engine if I could not find the issue with the pump. I am really getting tired of working on my back redoing things. BYW I noticed the oil pump gears are similar to my Buick V6, I would always run a diamond file along the top and bottom of the gears to remove any sharp edges. Another trick is to add one .100" hole in the gear that is not the drive gear. The hole would be mid point between two teeth. (you would have to deburr the inside of the gear). This will permit oil to lube the post the gear rides on.
1965 140 Corsa
1968 140 Monza convertible 4 speed
1965 Corsa Convertible
1966 Crown V8 383 435hp
1986 Buick GN V6 600hp
66vairguy
Posts: 4531
Joined: Tue Dec 21, 2010 3:44 pm

Re: Oil pump housing

Post by 66vairguy »

NO oil pressure regulator spring! I recall saying "the oil pressure regulator is not working correctly (unlikely if parts are good)".

Folks do make mistakes and some things should always be double checked. And this is why I now do all my own engine assembling and follow a checklist (and yes I do catch mistakes I make).

A 20PSI top reading was a warning something was amiss. The oil pump via the distributor drive shaft turns at half engine RPM and the average drill can exceed 300RPM and at 70F 10W30 will open the regulator to it's maximum reading of about 40PSI. Anything less than 35PSI from 300 to 1200 drill RPM indicates a problem with a newly rebuilt engine.

At least you stopped the engine in a short time and hopefully no damage was done and you found the problem.

Oh - while you are at it. The oil pump idle gear shaft in the housing often weeps oil. Hard to get at in the car, but with the housing off you can clean it and put some JB Weld over the area were the shaft is. I was dubious of this fix at first, but it works.
gnrand
Posts: 277
Joined: Sun Nov 15, 2015 8:10 am
Location: Wildomar,Ca

Re: Oil pump housing

Post by gnrand »

Yep, 50 psi with the same cordless drill. It took 6.5 qts. using the Otto pan. Tested the pressure after adding 3 qts and got the same 50 psi. Guess the gallery plugs are installed.
jeff
1965 140 Corsa
1968 140 Monza convertible 4 speed
1965 Corsa Convertible
1966 Crown V8 383 435hp
1986 Buick GN V6 600hp
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