Oil Pump leaking on rebuilt 1500

For Pre A discussions and questions
Post Reply
Message
Author
User avatar
Tom Sansone
356 Fan
Posts: 28
Joined: Fri Mar 28, 2008 8:45 pm
Location: Sacramento, CA

Oil Pump leaking on rebuilt 1500

#1 Post by Tom Sansone » Mon Jul 15, 2019 5:04 pm

Guys,

I am putting the finishing touches on my factory original 3 piece 1500 N engine # P 35039 which will be reunited with my 1955 Continental Coupe. The engine is on a test stand and after running it for a time, I noticed an oil leak dripping from the oil pump housing. This is the "small" oil pump. I had installed the pump with a gasket and a sealer before the test run. After finding the leak, I removed the pump cleaned the surfaces and re-installed the pump using a new gasket and a different sealer...Permatex Grey (a silicone based sealer). This time, the oil did not leak from around the housing but instead leaked from the tack drive shaft opening....a steady drip. Everything else seemed to be leak free.

I have removed the oil pump housing again and removed the tack drive after cutting the safety wire and removing the plug. There is a tack drive oil seal....I have ordered a new one from Stoddard....and a seal ring under the plug....I have also ordered a new seal ring. I also ordered new gaskets (more than one). When they arrive, I will be ready to re-install the oil pump housing again.

I am confused about a few things.

1. Should I mount the oil pump with or without a sealer on the new gasket?
2. There is a small hole on the under side of the housing which leads to the tack drive shaft. What is the purpose of this small hole and should I be careful not to obstruct it with sealer?
3. On the third piece, under the oil pump housing, there is a groove in the surface of the 3rd piece which circumnavigates the entire area under the housing. This groove ultimately leads to the opening where the pump gears are located and the groove seems to line up with the small hole I mentioned in question #2. Does this groove need to be unobstructed so oil can flow?
4. On the oil pump housing, there are two holes, top and bottom, which have threads inside. What is the purpose of these threaded holes?
5. If I use sealer when I mount the oil pump, what type of sealer should I use and how would you suggest I apply the sealer?

Any other thoughts or suggestions would be appreciated.

Tom Sansone
Elk Grove, Ca.
Tom Sansone
55 Coupe
65 Cab
Sacramento

User avatar
Norm Miller
356 Fan
Posts: 2182
Joined: Thu Mar 27, 2008 9:14 am
Tag: Official curmudgeon
Location: near Ft Collins

Re: Oil Pump leaking on rebuilt 1500

#2 Post by Norm Miller » Tue Jul 16, 2019 12:49 pm

Basically a simple answer;

Don't use a sealer!
I sometimes oil the gaskets to simplify shrinkage issues.

Are the cover surfaces "flat" as in not warped?

NORM
 

User avatar
Craig Richter
356 Fan
Posts: 947
Joined: Thu Dec 15, 2011 9:01 pm
Location: San Miguel de Allende/Traunkirchen

Re: Oil Pump leaking on rebuilt 1500

#3 Post by Craig Richter » Tue Jul 16, 2019 2:55 pm

Norm's answer is perfect, but maybe a little brief (He has been studying the Vic method of answering). There was a topic here a few years ago "Oil leak at oil pump". If you can find it on Google, follow Dick Weiss' advice. Norm's post on there was longer too.
The groove should be unobstructed, hence why you must be careful with sealer. The problem with the old "separate housing - little gears" oil pump your motor uses is that they are all pretty worn out by now and need the thinnest gasket possible with no sealer to maintain descent oil pressure. Heck, they needed that help when new!
I used to know what those top and bottom threaded holes were for, but I forgot, so they must not be too important. Maybe for pulling a tight cover? Except I don't remember the covers ever being very tight.
 

User avatar
Tom Sansone
356 Fan
Posts: 28
Joined: Fri Mar 28, 2008 8:45 pm
Location: Sacramento, CA

Re: Oil Pump leaking on rebuilt 1500

#4 Post by Tom Sansone » Tue Jul 23, 2019 12:27 am

Gentlemen,

Got it. No sealer.
I also sanded the oil pump surface on a piece of glass (nice and flat) using 320 grit sand paper. It seemed flat before but now it is smooth and very flat.
I used a new gasket and installed the pump without any sealer and torqued the nuts to @ 10 lbs. I started the engine and let it run for awhile and saw a small drip from the bottom of the pump.

I have additional gaskets and I will try again. I will also look up the article written by Dick.

Is it practical to use two gaskets to help seal the surface? Is there any other trick to preventing the pump from leaking?

Thanks for your time and effort

Tom Sansone
Tom Sansone
55 Coupe
65 Cab
Sacramento

User avatar
Vic Skirmants
356 Registry Member
Posts: 7161
Joined: Tue Oct 27, 2009 5:02 pm
Location: SE Michigan

Re: Oil Pump leaking on rebuilt 1500

#5 Post by Vic Skirmants » Tue Jul 23, 2019 7:44 am

"Is it practical to use two gaskets to help seal the surface? Is there any other trick to preventing the pump from leaking?"
NO, NO, NO. Are you sure the leak is not from the gasket between the pump body and the timing cover?

User avatar
Tom Sansone
356 Fan
Posts: 28
Joined: Fri Mar 28, 2008 8:45 pm
Location: Sacramento, CA

Re: Oil Pump leaking on rebuilt 1500

#6 Post by Tom Sansone » Mon Jul 29, 2019 7:51 pm

Well, well, well. I think Vic is correct. I crawled under the engine test stand to take a good look under the oil pump housing. I does appear there is some oil leaking out from under the "block" on which the pump housing is mounted. There is definitely a seam where the block meets the timing cover and it appears wet with oil. So....maybe the oil pump housing is not leaking....maybe the leak is between the timing cover and the block.

OK. Good suggestion Vic. Now....how do I remove the block and is the gasket under the block the same gasket that is under the pump housing? I remember seeing a special tool being used to remove that block. Is there a trick to getting that block off the 3rd piece...and do I use the same gasket as with the pump? I don't see a reference to a gasket in Stoddard's catalogue.

Thanks for all your insights.

Tom Sansone
Tom Sansone
55 Coupe
65 Cab
Sacramento

User avatar
Vic Skirmants
356 Registry Member
Posts: 7161
Joined: Tue Oct 27, 2009 5:02 pm
Location: SE Michigan

Re: Oil Pump leaking on rebuilt 1500

#7 Post by Vic Skirmants » Tue Jul 30, 2019 7:48 am

Yes; I don't see any reference to the pump housing gasket in the older Stoddard catalog here in the office. The newer catalog is in the shop.
It is a completely different gasket. PM me and I'll mail you a couple. To remove the pump housing, you will have to pry it out of the timing cover. It's getting complicated, so be sure you really want to tackle this.

User avatar
Tom Sansone
356 Fan
Posts: 28
Joined: Fri Mar 28, 2008 8:45 pm
Location: Sacramento, CA

Re: Oil Pump leaking on rebuilt 1500

#8 Post by Tom Sansone » Tue Jul 30, 2019 7:27 pm

Vic

Thanks for the response. I sent you a PM. I sent you my street address but I should have also included my email address which is trsansone@comcast.net just incase you need to tell me I am crazy to worry about this small oil leak between the timing cover and the oil pump block. I suspect the entire front of the engine will need to come apart to do this right.

Tom
Tom Sansone
55 Coupe
65 Cab
Sacramento

User avatar
Craig Richter
356 Fan
Posts: 947
Joined: Thu Dec 15, 2011 9:01 pm
Location: San Miguel de Allende/Traunkirchen

Re: Oil Pump leaking on rebuilt 1500

#9 Post by Craig Richter » Tue Jul 30, 2019 9:28 pm

Here is where you can use a little bit of sealer instead of a gasket if you can't find one. The oil pump body/timing cover interface doesn't see oil pressure, so leaks here are not common.
 

User avatar
Tom Sansone
356 Fan
Posts: 28
Joined: Fri Mar 28, 2008 8:45 pm
Location: Sacramento, CA

Re: Oil Pump leaking on rebuilt 1500

#10 Post by Tom Sansone » Wed Aug 07, 2019 10:06 pm

I want to thank Vic for sending the gasket which fits between the timing cover and the oil pump block. Now....to install it. Craig suggests a sealer can be used on the block with or without the gasket.

I have removed the timing cover and the oil pump cover. Now...how do I remove the block from the timing cover? Vic suggested I "pry" the block off the timing cover but I'm afraid that might do some damage to the timing cover or the block. I'm wondering if one could press the block out from the inside of the cover. Has anyone done this?

Tom Sansone
Tom Sansone
55 Coupe
65 Cab
Sacramento

User avatar
Vic Skirmants
356 Registry Member
Posts: 7161
Joined: Tue Oct 27, 2009 5:02 pm
Location: SE Michigan

Re: Oil Pump leaking on rebuilt 1500

#11 Post by Vic Skirmants » Thu Aug 08, 2019 7:40 am

If the cover is off the engine, yes you can push it out; it's not that tight.

User avatar
Tom Sansone
356 Fan
Posts: 28
Joined: Fri Mar 28, 2008 8:45 pm
Location: Sacramento, CA

Re: Oil Pump leaking on rebuilt 1500

#12 Post by Tom Sansone » Fri Aug 09, 2019 11:52 am

Guys,

I got the cover off the timing gear cover with a few raps from a plastic mallet. Vic was right again. It wasn't that difficult to get the block out of the cover. It was not as tight as I imagined.

Something interesting...there was no gasket between the block and the cover. There was however some sort of sealer...black...on all the mating surfaces. It was tenacious stuff. Some very fine steel wool, lacquer thinner and some elbow grease took care of it.

Now...to install the gasket Vic sent to me and put the thing back together. Craig recommended the use of a sealer in this process. What kind of sealer do you recommend between these two surfaces and on the gasket?

Tom
Tom Sansone
55 Coupe
65 Cab
Sacramento

Post Reply