spray bar gasket?

[Captain Obvious]

I've messed with a grand total of two spray bars so far, and one had gaskets while the other did not. No idea if someone had been in there messing around before me though.

Here's madkaw's thread you're looking for:

http://www.classiczcars.com/forums/showthread.php?23392-cam-oiling-investigation

I think the original spray bar implementation is very poorly done. The idea is great, but the implementation was a misapplication of materials.

[Bonzi Lon]

When my cam was replaced with an internally oiled one, the dealership used block off plates without any gaskets.

If this is not a highly modified engine you might look at "How to Rebuild (not modify) your Datsun & Nissan OHC Engine", pages 106-107, Inspect & Install Cam, & photo 6. Several points to take into consideration.

Bonzi Lon

[John Coffey]

The new RTVs are fine in this situation. The problem is the people applying it. More is not better.

[5thhorsemann]

Anyone know where to source the billet spray bar?

[John Coffey]

Larry Hassler 626-485-1556.

[steve91tt]

I tried the engine stand oiling technique outlined in Madkaw's thread above. I cut the handle off of a 12" flat blade screw driver and installed through the distributor drive hole. I turned the screwdriver with a drill (counter clockwise) and oil streamed out all 12 of the cam oil holes. Oil also appeared at each hole in the spray bar but the oil flow through the spray bar was very low. Oil was also leaking between the spray bar and the cam towers (no gasket). I don't have a oil pressure gauge installed so I'm not sure that I'm building enough pressure with the drill as the drill was not able to turn the pump very quickly. I'm going to try experimenting with another drill and I will also try removing the spray bar and blocking the holes.

I also confirmed that I have a high volume pump by taking it apart and measuring the rotor to be 40mm. I cut a new internal oil pump gasket out of gasket paper but I'm not sure that was the best way of sealing up the pump. I fear that the clearances in the pump are changed by the fact that the gasket paper is thicker than what was there previously. I tried bolting together the two halves of the pump without a gasket but in this configuration the pump was locked solid. Does anyone know if I should worry about the gasket paper or if a stock gasket is available anywhere? Neither MSA or the local autoparts story seem to have one.

Edited December 16, 2011 by steve91tt

[5thhorsemann]

I just finished doing a valve adjustment, they were getting a bit noisy and all the talk lately about wiped cams and busted spray bars had me nervous as a whore in church.

The valves were out a few thousands each, corrected that. The spray bar was leaking at the towers a bit so I refit the covers and put them back together using a very light film of LocTite gasket sealent. The spray bar is a real POS, it has loose braise joints and the tower castings are warped so I called Larry Hassler to find out about the billet bar, no answer, left a message. (Thanks John)

I am thinking of doing a cam swap, but the car runs so damn good that I cant see taking it apart right now. Besides the fact that MSA is not selling the rockers rite now.

I'll share the info when he returnes my call.

[Zed Head]

I tried bolting together the two halves of the pump without a gasket but in this configuration the pump was locked solid.

I really don't know much about oil pumps, I've never even had mine off, let alone apart, but the FSM, EL section, suggests that the pump should still turn with no gasket. Clearance is measured from the base of the pump body down to the rotor, implying that there is clearance without a gasket. This is from the 1976 FSM, which is better illustrated than the 1973 FSM.

Just an observation.

[steve91tt]

quick update...I tried removing the spray bar and blocking off the holes with fender washers (block off plates are on the way). The flow out of the cam oilers improved significantly. I also noticed that the oil system seems to drain fairly quickly in that it takes quite a bit of pumping to get the oil back up into the head even after the system was primed. Is this normal?

[5thhorsemann]

Oil filter check valve? Doesnt that prevent the oil from draining back to the pan through the supply journals in these motors?

oil flow.doc

[madkaw]

Not sure what your saying here??? Flow out the cam oilers improved(what do you mean by cam oilers?). I would associate cam oilers with the spray bar-but you say you removed it.

Oil shot out of the cam holes in my experiment. I was kind of suprised the pressure of the oil coming out. Don't remember how long recovery time was as far as getting oil back up to pressure.

I know it took a major drill to do this experiment.

quick update...I tried removing the spray bar and blocking off the holes with fender washers (block off plates are on the way). The flow out of the cam oilers improved significantly. I also noticed that the oil system seems to drain fairly quickly in that it takes quite a bit of pumping to get the oil back up into the head even after the system was primed. Is this normal?

[Captain Obvious]

Anyone notice that the holes in that billet bar are located farther away from the cam than the original bar?

I know, I know... If the tubes fall off of your original bar, then it won't matter how close to the cam they used to be, but has there been any discussion about that distance?

The reason I'm asking is because I just started a project of recreating my spray bar with a better design, and I was going to make the geometry similar to stock because I wanted the holes close to the lobes.