Can't get oil pressure up in my rebuilt flathead motor.....help?

`Hi, everyone.....just put a rebuilt flathead into my coupe and got it all ****oned up and started it up, but no oil pressure! Immediately shut it off....... I have pulled down the pan, checked the pump, put on a different oil pickup, different pan, different oil pump!!! Like that.......and I still can't get pressure to come up when I crank it over with the spark plugs out........I am sure that the bottom end is OK and I get oil out of the back of the block when I take the pressure sender out and crank on it....so the pump is definitely pushing oil to that point anyway....

I put a new cam in it but the cam bearings were Ok and I just slid the Isky in like it had eyes........all new valve train......Johnson lifters, Zephyr springs, etc.

I am using my electric fuel pump as I did with my old tired flathead and have tapped the fuel pump rod hole and installed a Permatexed plug in there......

I don't think the upper part of the motor is getting oil to all of the cam bearings.........I am really lost here......can't figure it out.....

Today I tried cranking it over and my gauge(electric) did show a buildup to almost 20 lbs, but would go no higher.......

Anybody got any ideas that I could look at tomorrow?? I plan to pull the intake manifold off and check a pressure relief valve I'm told is in the galley at the front of the motor??

Help??

Thanks for any ideas.......

Brucie

 

Grim knows what he's talkin' about. I'm diggin' into another and I'm making sure I put that plug back in.

 

If you have a canister filter, and don't put the restricter fitting on the inlet, you will not get all the oil pressure you deserve.

 

If a pre-49, ther'es a gallery plug at each end to forget. And a relief valve in main gallery to leave out...

 

Sorry....forgot to mention it's an 8BA '51 motor and I didn't do the rebuild, only the cam and valvetrain installation.......

Plug is definitely in the front of the oil gallery behind the cam timing gear....and there is no plug in the back.....only the idler gear cover....which is definitely on..

Tomorrow I will pull off the intake again and check that pressure relief valve in the front of the lifter galley.......I am not sure about that one.....

I am also running a Beehive oil filter with the same lines I used on my old engine.......old clapped out motor held 15 or so lbs. at idle and 30-40 when warmed up and revving down the road.......made funny noises over 3200 rpms though......

I'd give anything if I could have that oil pressure right now!!!

Thanks for your thoughts.....any others??

Brucie

 

I do have a Beehive filter hooked up with the same lines I used berfore and my pressure was fine on the old motor.......

Never heard of the Beehive needing a restrictor fittling......?????

Brucie

 

Stop! Ain't no relief valve to check there in an 8BA! And on the Beehive, for now just remove its feeder line and put a 1/4" pipe plug in the hole.
Ron has reported some current repro oil pumps for FH havwe a sloppy fit in block and dump oil pressure right there--something chilling to think about.

 

A cleanout plug would do it! If you've ever just stuck a flathead pump into a bucket of solvent and turned it by hand, you know it puts out a big, solid stream of oil. Takes a big leak to droppit to nothing.

 

I once had a machine leave out one of the oil gally plugs. It was dumping all the oil back into the pan and not through the block... That was one of my worst rebuild experances.

 

BTTT

 

Thanks for the suggestion Kevin......I should have checked the plugs while I was changing oil pans......

Do you know how many plugs there are and where they are located specifically?

Thanks....

Brucie

 

What kind of gauge are you measuring with? I think you said electric; is it a new gauge or the same one you had before the build?

Could you crank it over with the pan off and the pickup in a coffee can of oil? You'd make a mess but find out quick where the problem is...

 

You say you went with a bee hive filter.Look at your old canister on the side where the oil input line gos and see if it dont have a restrictor.I think the new filter is your low pressure trouble.Unrestricked line will give you low pressure on your flatty.

 

We fought this for a while in the blue tub....ended up pulling the motor all the way down to find the problem. Turned out the cam was .010 under and it didn't get measured. A new set of cam bearings fixed it right up.

Just something to think about if you're running a regrind.

 

I was wondering about the cam bearings when he said the cam "went in like it had eyes". With new bearings and a new cam, the fit is very close and the cam can take a bit to work through. But he's sure there's no oil getting up to the cam.

Flatman

 

Hi, Flatman...

and thanks for your thoughts.......I guess I may have been operating under an ***umption that when this motor was rebuilt that the machinist put in new cam bearings, part of any complete rebuild.......the motor did have a bit of run-in time on it when I got it.....

I miked the cam bearing opening and the cam bearing surface and there was about .002-.003 difference which I thought was well within spec for clearance........maybe I'm wrong about that.......

Since I was just able to get the gauge up to close to 20# pressure just cranking it with the starter, I may try again starting the motor and see what it comes up to.......I just don't want to hurt any bearings......

Any further thoughts? Thanks....

Brucie

 

The most common causes are that the oil-galley plug wasn't put back (but you checked this) -- the next most common on a 49 - 53 is the oil-cleanout plugs in the crank rod throws.

A 49-53 Ford crank has the smaller ones - seems they are 1/4" to 3/8" . . . the Merc crank has the larger 5/8" or so. On my first stroker motor (30 years ago), the machine shop put new plugs in my Merc crank, but didn't take a center punch and put a "pean" in the crank (couple places around each plug) to keep them from getting pushed out by oil pressure. Of cource, I was also running 40 weight oil. The Mellings 49-53 style pump pushed two plugs right out on the first start . . . pressure went to dang near zero. Luckily I shut it off and pulled the pan - before my bearings were wiped out.

Allen Plugs: When I build cranks today, I replace the cleanout plugs with threaded allen plugs -- they stay in place, regardless of high oil pressure.

You've already checked the cam bearings -- so that is the other common place to miss the boat. Also - you may want to check the oil-pump pressure relief valve - just to make sure it isn't stuck open (maybe a piece of **** stuck in it) -- it is on the side of the pump.

These engines have no rockers or other top-end to oil, so they really should have almost immediate oil pressure and lots of it.

 

Check that the crank has all four clean out plugs installed. They are located on the end of the center of the rod journals of the crank. I have had crank grinders leave these out, and customers don't notice it until they have no oil pressure... What about the oil pump push rod bushing? Are you running an electric fuel pump? Did you plug the bushing? If not, I make a plug that you can install. Also, like the other fellas say, make sure the oil galley plug behind the cam gear is in place.

 

btt

 

Hey Brucie!!----------Time to put that SB Ford motor in!!!!!--------------Don

 

So...what did happen in this ancient thread?? I'm betting that plugging off the beehive cured it...that 20 on the starter only is not bad.
And the small block Ford went belly-up when its ridiculous pump drive rounded off its corners and killed ITS oil pressure...