The following are the highlights of some Q&A I had with JWL about concerns after finding the Offenhauser 4BBL intake casting would not clear the heel of my stock 59A fuel pump tower as the mounting position is not offset. It seems they use the same casting and open the manifold as necessary for the 8BA crankcase breather.
The solution at that time was to have a spacer made to elevate the tower and use an 8BA pushrod.

Hi John, If not too much trouble I'd like to ask your opinion.

As you suggested, I did have a spacer made to elevate the fuel pump to clear the casting on the 4BBl intake. I raised it 1" with thoughts of using a later model push rod. Of course, another pitfall, the diameter of the rod is larger. I may have it turned top and bottom even though it's hardened.

The reason for all this is I wanted to maintain the complete breather/oil blowby baffle as original. I feel if Ford put it there, it should stay.

The obvious solution is to plug the push rod opening, however I'd like to be able to remove it to allow for a different intake should I decide to use a standard fuel pump.

1; Is the oil pressure at the push rod outlet the same thruout the engine, 60# at the gauge 60# on the rod?
2: What would you suggest an aluminum plug (my oil pressure concern) or tap the block for a bolt?
3; Can the whole thing, plug the hole, use a fuel pump blockoff plate, utilize the stock breather tube without the spacer and an electric fuel pump?

Any insight you can pass on will be appreciated.
Thanks, BillB

Bill, you asked a couple of questions about the oiling system of your 59A and commented that you wanted to retain the complete breather/oil blowby baffle at the fuelpump stand. Your primary question was:

1. "Is the oil pressure at the fuelpump pushrod opening the same thruout the engine, 60# at the gauge and 60# on the rod?

Let's see if I can explain some things here so you have more information available to make your decision.

As the pressurized oil leaves the pump it goes directly into two passages. One to the rear main bearing saddle, and one to the oil manifold (tube) in the lifter galley which runs from the rear of the block to the front. On the way to this oil manifold there are a couple of outlets on the outside of the block for a gauge and filter.

From this manifold (tube) oil is directed to the center and front cam bearings and from them to the center and front main bearing saddles. At the rear of the block an oil passage intersects the passage from the pump and is drilled for a short distance directly in line with, and toward, the oil manifold (tube). Beyond this short distance, and approximately centered on the fuelpump pushrod, the block is hollowed out. The drilling then continues on the other (front) side of this cavity untill it reaches the oil manifold (tube). 90 degrees vertical to this drilled passage and cavity area, the fuelpump pushrod bushing bore is drilled and reamed. The pushrod bushing is a tight press fit at the top and bottom of this reamed hole, but in the middle section, in line with the oil manifold, is the hollowed out or "cavity" area which allows the oil to flow around the outside of the bushing. There is direct oil pump pressure surrounding the pushrod bushing as it makes it's way to the oil manifold. If you would remove the bushing, which is approximately 1 1/2 inches in length, you would see the bushing fits very tight at the top, and very tight at the bottom near the cam bearing, to seal off the passagway cavity. If there is no hole in the pushrod bushing, there will not be any lost pressure. The presence of the pushrod is irrelevant. I have seen bushings which were worn thru which caused a major loss of oil pressure. Also, some Lincoln and Mercury engines were built with bushings which had a small hole drilled in them to provide lube to the pushrod.

I like to plug the pushrod bushings, which are not to be used, to eliminate the splashing of oil which gets thrown up to the intake manifold, and to ease the mind of owners about lost oil pressure. But again, there will be NO OIL PRESSURE LOST IF THE BUSHING IS GOOD AND IN PLACE.

Now you further have asked about the quote from the Flathead Jack catalog:

"When removing the old fuelpump rod from the rear of your flathead block, you will need to plug the top hole to prevent oil loss. Also ask your machinist when installing the rear cam bearing to rotate it 1/4 turn thus blocking off the bottom opening."

This Flathead Jack scenario is an old "fix" that some racers used. However, the sentence quoted does not give you the facts. Removing the pushrod will not affect the oil system unless the bushing is also removed. For racing, the cam bearing is turned so the hole where the pushrod fits thru to run on the camshaft is away from the bottom of the oil "cavity" in order to seal the bottom of the cavity hole. The pushrod bushing is removed and then the top of the reamed hole is plugged with a short plug. This uses the outside of the cam bearing to seal off the oil cavity and with the bushing removed allows the oil a straight shot into the oil manifold without going around the bushing. The Flathead Jack system would not do anything unless the bushing was removed rather than just the pushrod. The problem with turning the cam bearing is that you cannot later install and use a pushrod without major work. Frankly I think it is a waste of time anyway. And, I like to use the alignment of the holes to identify exactly where to place the bearing when pressing in a new set.

I use a 3/8 ball end carbide burr with 6 inch X 1/4 inch shank to do oil porting in the cavity area before installing a new pushrod bushing. This eliminates any potential restriction caused by casting shift and insures that the bushing doesn't hamper flow.

Most people who understand the crankcase breathing system, agree the baffle below the fuelpump stand is a good idea. However, many engines have run many miles, without a baffle there.

If you need more information or if this doesn't make sense, let me know.

Best Regards,

JWL

My conclusion! I have installed an aluminum tapered plug in the pushrod bushing to prevent any crank oil splash. Also, I'm using the stock fuel pump tower with a pump blockoff and the complete original breather/baffle tube. Fuel supply will be by electric pump.

BillB

Return to Index Page