lost my oil pressure

[62 Max]

Since you have the pump off,you may want to take the cap off and check the relief valve.They have been known to stick.Also,on a rebuild you should have more than 30lb pressure.A pump has to be pretty bad to make no more than 30lb.As for you engine builder I would have seconds thoughts after reading your post.

[69 rt]

Your right, You hear good things about a shop and in the end you can be one of the unlucky ones. It is possible giving the guy the benefit of the doubt that is was one missed out of many. I hope!

[firefighter3931]

OK, I will pull the pan, good advise, one other question. After I replace the oil pump should I prime it prior to starting the engine and if so is there a tool available to use with a drill to prime it?

The priming rod that john linked to above will work fine....use a drill and rotate counerclockwise. You might have to keep rotating the engine over until the #4 cam bearing is lined up with the oil hole and you see oil coming from both rocker shafts. I also like to use a little white grease inside the pump to help it prime.

Good luck. 




Ron

[69 rt]

I sent for the tool you mentioned and I want to thank all who have responded for you help.

[69 rt]

Well I think I got lucky, checked everything out and as far as I could tell there was no damage.  I replaced the oil pump and now show around 62lbs of pressure at start up and after it is warm it carries around 43. The engine sounds good no Knocks. Thanks for your advise.

[firefighter3931]

Well I think I got lucky, checked everything out and as far as I could tell there was no damage.  I replaced the oil pump and now show around 62lbs of pressure at start up and after it is warm it carries around 43. The engine sounds good no Knocks. Thanks for your advise.

Yep, you did get lucky ! 

Did you look at any of the main/rod bearings ? 



Ron

[RD]

what oil you running?  is it a stock oil pump?  curious is all,  not worried.

[CB]

wow Stenton, glad to see it turned out well with your beautiful R/T!! 
CB

[69 rt]

Thanks CB, sometimes we get lucky, Also for RD I use Mobil 1 synthetic with an additive, the oil pump I replaced is a H/P stock mounted pump.

[69 rt]

Well guys I am back to square one, put on the new pump, changed the oil and filter and went for a drive. As the engine got warmed up the oil pressure dropped to 25lbs. Drove the car home, shut it off and then after 20 minutes I started it up and the oil pressure stayed at zero and it started making lifter noise. I shut it down and pulled the distributer and attempted to pull oil using my drill and the oil pump tool with no luck. I drained the oil and removed the pan and checked the pickup tube and strainer, both good. I then pulled the cap off one of the main bearings and it looked ok. My question is even with a new pump could the pressure relief valve be sticking and causing the problem? I removed the spring and valve and it also looked and worked ok. I am sure someone on the site has had this problem so any help would be appreciated. The gear that drives the pump is good.

Thanks

[ACUDANUT]

Damn, again ?  Where is this pressure relief valve with a spring in a oil pump ?  Never heard of it ??

[superblu72]

Have you taken off your valve covers? I had the zero oil pressure happen to me twice w/tapping sounds. Turn out that on the one I bent a pushrod and it thru the lifter out of the bore and the other broke ball/cup end off pushrush and also thru a lifter out of it's bore.

[firefighter3931]

Well guys I am back to square one, put on the new pump, changed the oil and filter and went for a drive. As the engine got warmed up the oil pressure dropped to 25lbs. Drove the car home, shut it off and then after 20 minutes I started it up and the oil pressure stayed at zero and it started making lifter noise. I shut it down and pulled the distributer and attempted to pull oil using my drill and the oil pump tool with no luck. I drained the oil and removed the pan and checked the pickup tube and strainer, both good. I then pulled the cap off one of the main bearings and it looked ok. My question is even with a new pump could the pressure relief valve be sticking and causing the problem? I removed the spring and valve and it also looked and worked ok. I am sure someone on the site has had this problem so any help would be appreciated. The gear that drives the pump is good.

Thanks

Inspect the oil pump drive closely.....make sure the gear is pressed onto the shaft firmly. I've seen a few that "looked" good but the gear was loose. I prefer to run the pinned oil pump drives for this very reason.




Ron

[six-tee-nine]

Ron,

about the pinned drives...... what make do you mean then?

(trying to learn about this stuff)

[firefighter3931]

Ron,

about the pinned drives...... what make do you mean then?

(trying to learn about this stuff)

Several vendors sell them....Mopar Performance, Milidon, 440 Source.



Ron

[69 rt]

Well here is the latest on my problem. After two days of checking the main bearings which were in very good shape and gauged ok using plastigauge, changing the oil and filter, removing the oil pump and checking the pressure relief valve. I put it all back together and primed the pump and took it for a drive of approx 30 miles. The pressure started out at 62lbs and did not drop below 40, so all I can think is the pressure relief valve must have stuck. I hope this info might help one of you all if this problem ever happens to you.

69 rt

[ACUDANUT]

Pressure relief valve must have stuck Where is this valve that you are refering to ?? 

[62 Max]

Right here.

[ACUDANUT]

 WOW, I guess I never knew that. Thanks

[troy.70R/T]

so is that oil pump priming tool just a pieace of 3/8 hex shaft? That would only cost me $1.00 At My local steel supplier?

[Charger-Bodie]

so is that oil pump priming tool just a pieace of 3/8 hex shaft? That would only cost me $1.00 At My local steel supplier?

It is. BUT its heat treaded to a hardness as to not wear ot fast.

If you will only use it a couple times I dont think it would be a problem.