Pre-Start Priming of a '72 F Engine (1 Viewer)

[VooDooBlu72]

I've got a '72 F-155 engine that's been completely rebuilt with new pistons, rings, cam, lifters, bearings, seals, and gaskets. I've even added a few improvements such as 2F valve cover, power steering, throttle body fuel injection, ceramic coated header, and electronic ignition to name a few. That's it in the first picture. Perdy, Huh?

I'm getting ready to fire it up for the first time and decided to prime the oil system before I set the distributor. To do this I used a tool I made to spin the oil pump using a cordless drill.

I removed the valve cover so I can see the oil come out of the rocker arms and then fired up the drill. Unfortunately, after several minutes of spinning the oil pump I got no oil at the rocker arms. None. Nada. Zilch. I got pissed is what I got!

After a few moments commenting to the engine about the questionable marital status of its parents at the time of its birth, I decided to check the oil filter to see what was going on over there. An attempt to remove the externally mounted spin-on filter revealed it was full of fresh clean oil. Thus confirming the pump was indeed pumping (So, I have that going for me. Which is nice!).

For those unfamiliar with the F's oil system, here's the Reader's Digest version: From the pump the oil takes one of two paths. Some goes through the (externally mounted) oil pressure regulator to the oil filter and then straignt back to the oil pan (via two external oil lines). The other path is directly to all the various internal pieces and parts (crank/cam bearings, timing gears, lifters, rockers, etc.).

In order to get the oil up to the rocker shaft and rocker arms, the oil must travel via a little copper tube from the block, through the head, and into the rocker tube. That tube is shown in the second and third pictures.


I have since ensured that (1) that little copper tube is clean and free of obstructions and (2) properly installed.


So, with all that being said, anyone got any ideas as to why I'm not getting any oil pressure on the top end? I sure hope so, cuz I'm all out.


Steve

 

[ColonelMustardFJ40]

I think the #4 cam bearing supplies the oil to the copper tube and if that is not lined up with the oil hole in the cam shaft you will not likely see oil to the rocker set. Turn the engine over by hand while running the drill and if all is well you will get oil to the top end.

 

[vtgbeemer]

Steve
I ran into the same scenerio. I spun it for what seemed like forever with no oil up top. Pulled the oil filter and it was full. Before doing that I spun it with the oil sending unit out and it really spurted. Spun it again with a corded drill for a while and decided it needed help. I had prelubed everything during assembly so I took a chance by drenching everything in the top end and stabbed the distributor and fired it up. I did this from under the hood so I could let it run a few seconds while I watched and then cut it off. I felt pretty confident that I was oiling the bottom end all along and the top end does not get much anyway so I figured my manual oiling was sufficient. Drenched it again and fired it up and viola!!!!! Success. I left the valve cover unbolted to I could check it a few times and it was fine after that. I am not necessarily recommending what I did but it worked for me. Keep us posted.
Craig

 

[B y r o n]

Could be that the drill method just does not create enough RPM to create enough pressure to get the oil to the top of the motor. With oil going through the filter and back into the pan not much pressure or speed is probably required. Try blocking off the oil line to the filter and see if the oil will then reach the top end.

 

[VooDooBlu72]

Thanks for the comments & suggestions.

Byron - The power drill is capable of spinning the oil pump at a very high RPM so I don't think it's a lack of pressure. I'm more inclined to think the cam is not aligned with the oil holes based on what others have said about not getting pressure until the engine is running (i.e. the cam is spinning / changing position).

I already thought of blocking off one of the oil lines and stopping oil from going to the filter. Unfortunately with the header on, I can't get to the oil pressure regulator to insert a plug in place of the oil line. I also tried to insert a bolt into the return line hole in the oil filter housing. Regular bolts (with the same thread as the hollow bolt that goes through the oil line banjo fitting) don't seem to fit. I tried several different ones. The hollow bolt seems to be a slightly smaller diameter. That leaves only capping off the oil line where it returns back to the block. That requires a cap with that stupid British Standard Pipe Thread (BSPT) to screw over the threaded end of the oil return line. I'm fresh out of one of those.

My next attempt will be to rotate the crank (and thus the cam) a little and then fire up the drill. I'll continue that thru a couple of rotations and see what happens. Wish me luck!

 

[DSRTRDR]

the air cleaner hurts my eyes - just sayin'

 

[VooDooBlu72]

DSRTRDR - The air cleaner, Huh?
The K&N filter is just wrapped in plastic to keep it clean while the rest of the rig is still under construction. It's been a multi-year process to get it to this point and my garage can be a bit dusty sometimes.

The air filter assembly itself is from Downey Off-Road (remember them???) and is a tw-piece cast aluminum setup designed for the Chevy TBI system I've installed.

Steve

 

[FJ40Jim]

The oil passage through the #2 cam bearing is only open 2X in each revolution of the camshaft. The only way oil will get to the rocker is if the engine has accidentally been parked at the one crankshaft position that allows oil flow.

Post #3 pretty well covers the startup procedure.

 

[MyTwoToys]

Priming an F engine

I just primed my rebuilt F today and had a similar experience to these folks. I ran the drill to prime the engine with no luck. Checked the flow into and out of the oil filter and all was good. Came in and read this thread. The best advice was to hand crank the engine while running the drill to prime it. Once I hand cranked the engine the oil flowed to the top of the valves with no issue. Thanks for the advice. Keep on cruising.

 

[cult45]

Re sparking an older thread. Did you replace your copper tube or was yours good to reuse? Looking to replace mine and need a source.

 

[MyTwoToys]

I did not change my tube, I guess I should have since about 20 days after I got the engine running I seized the thing. Not sure where you might be able to source one in your neck of the woods. Happy New Year. Hopefully 2015 is the year I finally get my rig on the road for good.

 

[cult45]

I did not change my tube, I guess I should have since about 20 days after I got the engine running I seized the thing. Not sure where you might be able to source one in your neck of the woods. Happy New Year. Hopefully 2015 is the year I finally get my rig on the road for good.

I found a parts source, but thanks anyway dude. Sorry to hear about your engine. FYI SOR has them, or a hydraulic store near you. 3/16 pipe and olives [compression fittings] to suit. Cost me about $23AUD for enough parts for two.

 

[sggoat]

Thanks for the comments & suggestions.

Byron - The power drill is capable of spinning the oil pump at a very high RPM so I don't think it's a lack of pressure. I'm more inclined to think the cam is not aligned with the oil holes based on what others have said about not getting pressure until the engine is running (i.e. the cam is spinning / changing position).

I already thought of blocking off one of the oil lines and stopping oil from going to the filter. Unfortunately with the header on, I can't get to the oil pressure regulator to insert a plug in place of the oil line. I also tried to insert a bolt into the return line hole in the oil filter housing. Regular bolts (with the same thread as the hollow bolt that goes through the oil line banjo fitting) don't seem to fit. I tried several different ones. The hollow bolt seems to be a slightly smaller diameter. That leaves only capping off the oil line where it returns back to the block. That requires a cap with that stupid British Standard Pipe Thread (BSPT) to screw over the threaded end of the oil return line. I'm fresh out of one of those.

My next attempt will be to rotate the crank (and thus the cam) a little and then fire up the drill. I'll continue that thru a couple of rotations and see what happens. Wish me luck!

First of all--That is a clean, beautiful engine!!
As for the oil pump--it's a gear pump(positive displacement) - you should be able to turn it at ONE rpm and still get oil out of the discharge. As long as the pump suction is below the oil level in the pan, it should immediately pick up oil and pump it onwards. There are only two scenarios I can think of that would cause no oil at the outlet(cam).--Unlikely there would be any pluggage in the feed lines - this is posi disp--it'll blow the pump or rupture a line, or open the bypass.
The bypass regulator(all posi disp pumps have them)is stuck open, allowing all the discharge oil to return back to the pan, thus never building enough pressure to force the oil up to the top of the camshaft. I don't know what the bypass regulator is supposed to bypass at full discharge block(flow), but it is designed to maintain ~ 55 psi oil pressure.
2. The pump internals are worn beyond serviceability-if the gears or housing are worn severly, the pumped fluid(oil) can bypass around the gears--the pump essentially becomes a centrifugal one, simply spinning around without pumping anything(this is unlikely)
My .02

 

[Swompdog]

How do you make the attachment for the drill to prime the oil pump

 

[FJ40Jim]

Use a scrap vac retard distributor, remove gear off bottom, remove dissy guts, chuck in drill.

 

[MyTwoToys]

I used an old long handled screwdriver. Cut the head off and it fit in the drill chuck just fine. Good luck.

 

[Swompdog]

Does the banjo oil fitting need a rubber seal where it enters the rocker tube? It seams that the metal to metal connection would leak?

 

[FJ40Jim]

There are o-rings that go with the banjo fitting on the rocker shaft.

 

[Swompdog]

How many and where do they go?

 

[FJ40Jim]

2 orings, one for front half & one for back half of rockershaft. IOW, one for each side of banjo.
I'd have to go dig one out of the pile to see exactly how it goes together.