Getting Oil to the Overhead Conversion

rogeroadster

Senior Member
I have a (somewhat) stock B engine with a Steve Serr overhead conversion and a high volume oil pump that creates 30psi pressure to the galley after the full flow filter . Once the oil reaches the galley there is not enough oil pressure to pump oil through the external line to the head to oil the rockers. I'm guessing that I'm going to have to install a restrictor in the front of the galley but somehow still deliver enough oil to the dipper tray. Could any of you overhead guys enlighten me on this? To preclude some of the obvious questions, I have punched the necessary holes in the side cover gasket and it is stock oil to the mains and dippers to the rods.
 
I have a (somewhat) stock B engine with a Steve Serr overhead conversion and a high volume oil pump that creates 30psi pressure to the galley after the full flow filter . Once the oil reaches the galley there is not enough oil pressure to pump oil through the external line to the head to oil the rockers. I'm guessing that I'm going to have to install a restrictor in the front of the galley but somehow still deliver enough oil to the dipper tray. Could any of you overhead guys enlighten me on this? To preclude some of the obvious questions, I have punched the necessary holes in the side cover gasket and it is stock oil to the mains and dippers to the rods.

If you have a measured 30 psi after the filter, you should have plenty of pressure to oil the rockers. The question(s) I would have is what kind of pressure do you have at the external line where it enters the head? I would measure it there as you may have a side-plate gasket that is leaking at the lower oil channel.

Also, have you checked for a blockage at the head by blowing air thru the line that is entering the head where you can listen for the air to escape at the rockers? Also, are you certain the oil line up to the head is sufficient in size to carry the necessary oil volume?
 
The trouble starts when oil flow is diverted,oil flow is critical for splash side of the system.That being said 30psi In the gallery should be more than enough to supply flow to the head provided the feed isn't plugged.
 
Another option is an adaptor between the full flow filter and it's mounting base, to draw off filtered pressurised oil for the OHV.
 
Just as a matter of information, many of the OH conversions back in the day had no pressure oil to the rocker arms. They just had a 3/4 inch thick felt pad laying on top of the rocker arm assembly that they saturated with oil at regular intervals.
 
Another option is an adaptor between the full flow filter and it's mounting base, to draw off filtered pressurised oil for the OHV.

I have given this some thought. Then I'll probably be installing a restrictor at the head to reduce the flow as recommended by the head manufacturer.
 
If you have a measured 30 psi after the filter, you should have plenty of pressure to oil the rockers. The question(s) I would have is what kind of pressure do you have at the external line where it enters the head? I would measure it there as you may have a side-plate gasket that is leaking at the lower oil channel.

Also, have you checked for a blockage at the head by blowing air thru the line that is entering the head where you can listen for the air to escape at the rockers? Also, are you certain the oil line up to the head is sufficient in size to carry the necessary oil volume?

with 30psi input to the middle of the galley , the pressure measured at the rear of the galley is 4psi. The pressure at the front of the galley is not enough to travel up the 1/4" external line to the head. It is just enough to piss a little bit out the fitting if I remove the line while cranking the engine over. Yes I've checked for blockage. It's a mystery to me. I think I'm going to have to pull the side cover and investigate further (again).
 
Putting a restrictor at the head will be of no help at all, a line like katy suggested is your best bet. If you have 4 psi at the rear of the galley, use that as a source. Al you need is a slow drip off the rocker arms.
 
Putting a restrictor at the head will be of no help at all, a line like katy suggested is your best bet. If you have 4 psi at the rear of the galley, use that as a source. Al you need is a slow drip off the rocker arms.

how about adding a restrictor at the front of the galley if I did that what size hole would provide adequate flow to the dipper tray but still increase oil pressure?
 
I don't recommend doing that as that is the main supply for the rod dipper tray.

OK I'll follow that recommendations. Thanks. After considering everyone's input I think I'm going to reroute the the external line that feeds oil to the head. I'll post a picture as soon as I get it done.
 
OK I'll follow that recommendations. Thanks. After considering everyone's input I think I'm going to reroute the the external line that feeds oil to the head. I'll post a picture as soon as I get it done.

Here's my rerouted oil line to hopefully get more oil to the rockers...
 

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I have a stock B engine with an original Cragar OHV conversion that I recently finished. The only modification was a full flow oil filter similar to your set up. I was taking oil for the head off the rear of the oil galley and did not have enough pressure to get enough oil up to the head.

I installed a fitting for a 1/4 inch line in the top of the oil filter adaptor and ran that line up to the head. It now appears I am getting plenty of oil to the head.

You are on the right track.

Do not put a restriction in the front of the oil galley, you may starve the dipper tray.

Chris W.
 
My block has full pressure oiling using the oil pump from Turlock Machine. It uses all the internals from a Small Block Chevy oil pump. Getting oil to the head is no problem.

20190602_162411.jpg
 
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