Help 351C 4V Drivers side head not getting oil when priming motor

Hardfacer · Nov 14, 2024

Put motor together and went to prime before starting. Ran oil pump CCW, Gauge showed 90psi on gauge. Ran for a while with drill and rotated the crank also. Got oil up on the Passenger side head but nothing on the Drivers side. Did I not run long enough is there possible blockage that is not feeding oil to the right side What could cause this?

basstrix · Nov 14, 2024

Where is the gauge connected and how long did you run it?

Here's a diagram of the oil system.

Hardfacer · Nov 14, 2024

The gauge is on the back of the intake. We turned the pump using a ratchet and it built up that much pressure that it sprung back if it would slip out of your hand.
We then used a drill to turn the pump several times maybe 1 minute continuous at most. Would an incorrectly installed head gasket cause this?

ReBeLLangley · Nov 14, 2024

Hardfacer said:
The gauge is on the back of the intake. We turned the pump using a ratchet and it built up that much pressure that it sprung back if it would slip out of your hand.
We then used a drill to turn the pump several times maybe 1 minute continuous at most. Would an incorrectly installed head gasket cause this?

Head gasket has nothing to do with it. Rotate the crank slightly by hand while turning pump and see if that helps.

giantpune · Nov 14, 2024

Hardfacer said:
The gauge is on the back of the intake. We turned the pump using a ratchet and it built up that much pressure that it sprung back if it would slip out of your hand.
We then used a drill to turn the pump several times maybe 1 minute continuous at most. Would an incorrectly installed head gasket cause this?

If you hook up a drill to the oil pump and crank it, you should see oil coming up to each head, oozing out the ends of the pushrods, onto the top of each rocker. I don't think there's a way to install the head gasket so wrong that would prevent that.

Run that bad boy till the drill smokes.

MAD IRISHMAN · Nov 14, 2024

Hardfacer said:
The gauge is on the back of the intake. We turned the pump using a ratchet and it built up that much pressure that it sprung back if it would slip out of your hand.
We then used a drill to turn the pump several times maybe 1 minute continuous at most. Would an incorrectly installed head gasket cause this?

Perhaps your drill doesn't have enough "***" to get the oil moving. Used to be when I used 10W40 racing oil my 3/8" drill wasn't up to the job. It took my 1/2" Black & Wrecker drill to get things moving.
If that doesn't pan out, there must be a restriction from the back of the passenger oil galley to the crossover for the driver side galley. Or heaven forbid you got the rear main bearing installed incorrectly.

Hardfacer · Nov 14, 2024

Thanks I'll try running the Oil pump longer and faster to try and get the oil to get through to the other head. Maybe I didn't give it long enough. I do not want to rip the motor apart. We were leaning towards the head Gasket but sounds like we can rule that out.

rcadd1ct · Nov 15, 2024

Also turn the crank a quarter turn, then spin the pump again.

Do this until the crank is back where you started.

Look in the valley when you are doing this and make sure you don’t have a lot of oil escaping the lifter bores.

basstrix · Nov 15, 2024

Hardfacer said:
The gauge is on the back of the intake. We turned the pump using a ratchet and it built up that much pressure that it sprung back if it would slip out of your hand.
We then used a drill to turn the pump several times maybe 1 minute continuous at most. Would an incorrectly installed head gasket cause this?

Sounds like you haven't run the pump long enough. Run it with a drill for a minute, then rotate the crank 90 degrees and repeat. It's probably just filling up the lifter galley on the left side.

tony-muscle · Nov 15, 2024

If you have hydraulic lifters I agree with turning the crack if you want to make sure.

Hardfacer · Saturday at 9:00 AM

Hardfacer said:
Thanks I'll try running the Oil pump longer and faster to try and get the oil to get through to the other head. Maybe I didn't give it long enough. I do not want to rip the motor apart. We were leaning towards the head Gasket but sounds like we can rule that out.

Ok it took ran the pump 1 min then rotated crank 90 deg 4 times. R side was pushing oil in 45sec

Hardfacer · Saturday at 9:17 AM

Just ran he pump for 3 min right head had good flow right away but nothing on the left head. What do I look for next?

mrgmhale · Saturday at 10:52 AM

basstrix said:
Where is the gauge connected and how long did you run it?

Here's a diagram of the oil system. View attachment 95141

That isa a nice graphic layout. I have saved it for later reference, and inserted this into the For Shop Manual PDF files I have, in the engine lubrication sections.

MAD IRISHMAN · Saturday at 11:12 AM

Try removing a rocker arm and push rod on # 8 cylinder. Take something like an inspection flash light and look down the hole. Is there any oil coming up around the lifter(s)?

giantpune · Saturday at 11:17 AM

Hardfacer said:
Just ran he pump for 3 min right head had good flow right away but nothing on the left head. What do I look for next?

It sometimes take a lot longer than expected. And if you have a second pair of hands, have somebody continuously rotate the engine while you prime it. Can you tell if the lifters are getting oil filling them?

If you still can't get anything, perhaps the oil galley plug came out (or forgot to get inserted). Sometimes hotrodders drilled holes in the plug. I guess if you went with too big of a hole, it would make it harder to get oil up to the head.

MAD IRISHMAN · Saturday at 1:13 PM

Did you tap the gallery holes and put in threaded plugs in the rear oil gallery openings? Possibly put a longer pipe plug or screwed one into far? That will restrict if not cut off oil transfer to left side gallery.

Cleveland Crush · Saturday at 1:28 PM

Since your getting 90psi oil at the rear oil port take @MAD IRISHMAN recommendation to check #8 lifter for oiling. Since oil is making it to the oil sender port, check if it's making it next-door to the #8 lifter. If nothing at #8 there's your problem. Good luck.

Hardfacer · Saturday at 5:27 PM

Tried again, rotating crank and running oil pump. No luck also removed #8 pushrod and not seeing any oil on lifter. Leaning towards galley plug being to deep. If I pull the motor is there access to that plug behind the pressure plate?

Cleveland Crush · Saturday at 7:01 PM

Hardfacer said:
Tried again, rotating crank and running oil pump. No luck also removed #8 pushrod and not seeing any oil on lifter. Leaning towards galley plug being to deep. If I pull the motor is there access to that plug behind the pressure plate?

If you choose there is no need to pull the engine; "just" drop the tranny, bell housing and rear engine plate. You'll then have access to the rear oil gallery plugs. BUT may be best to pull the engine for a thorough tear down/inspection of the rear oil cross over route.
FWIW I like to prime the engine on the stand to verify oiling.

Hardfacer · Sunday at 6:26 AM

We pulled the motor and took the plugs out on rear of block right side filled with oil left side dry. Looks like a total tear down unless we can figure this out.

Help 351C 4V Drivers side head not getting oil when priming motor

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