No oil pressure!

[Wayne Kever]

I recently sent out the gauges and distributor for a rebuild on my wife's '54. The only gauges not sent were the speedo, ammeter, and oil pressure, which had always worked. Got everything back, had fun getting the distributor in right, finally got it. Great.

Fire it up to set the timing. Ready to go for a ride.

Notice zero oil pressure. No unusual sounds, though. Disconnect line from back of gauge and fire engine. No oil comes out. Either there really is no pressure, or the line is clogged. Suck on the end of the line. Can get some air, but no oil. Since there are no bad noises, decide to go for a short spin.

On the way back, a squeaky sound starts, like a rocker arm not getting oil. Limp home slowly. Sound never gets too bad, but now I believe the gauge. After shutting down, some smoking is seen through the vents in the valve cover.

OK, so now I believe there is no oil pressure, but don't have a clue as to why. Are the oil pump and distributor both driven from the cam? There was no warning in the service manual regarding the possibility of disengaging the oil pump when installing the distributor.

Any suggestions on what to check next?

- Wayne

[Joe L.]

Re: No oil pressure!

Wayne-----

On 6 cylinder Chevrolet 235 engines the distributor is driven by a gear on the camshaft which mates with the gear in the distributor mainshaft. In addition, their is an extension of the distributor mainshaft which has a "keyed" end. This "keyed" end fits into the engine oil pump and is what drives it. Actually, the system is similar to Chevrolet V-8s, except that on V-8s there is a seperate, intermediate shaft which fits between the oil pump and the "keyed" slot in the bottom of the distributor mainshaft; on the 6 cylinder there is no seperate, intermediate shaft inasmuch as the distributor mainshaft is extended below the gear.

Somehow or another when you remounted the distributor on the engine you must have not gotten the shaft engaged in the oil pump. Actually, I don't see how this could happen and still have the distributor fully seated in its mount, but that's all that I can imagine. Chevrolet 6 cylinders are not an area of expertise for me, though, so maybe some other member will know more.

[Scott Marzahl]

Re: No oil pressure!

Was the engine recently rebuilt. Is it possible that the oil pickup could have come loose or fallen off of the oil pump. This will cause a loss of oil pressure. This would require dropping the oil pan to take a look.

[Wayne Kever]

Re: No oil pressure!

No recent rebuild of engine. Only removal of distributor for rebuild, and replacement today.

Joe's theory sounds right, but I can't figure out how that came to pass. I'll see if I can get it to go further down in the block.

- Wayne

[Chuck G.]

Re: No oil pressure!

Hi Wayne. EMailed you already. It's possible that the octane selector/vacuum advance unit is preventing the distributor from being shoved fully into the block. As Joe has said, it works just like a V8 system in which you have to line up the slot in the pump with the tang on the end of the distributor. Let us know how you make out. Chuck

[Jerry Clark]

Re: No oil pressure!

Hi Chuck:

Like Joe, I don't understand how the distributor could have been locked down without the drive being properly seated in the pump key. I will be very interested to hear the results of Waynes investigation.

jerry

[motorman]

Re: No oil pressure!

could the pressure relief valve in the pump stuck open and cause no oil pressure? i have seen this happen on older cars because of the sludge in the pan,also the pick up screen may be plugged or came off. try turning the pump in the reverse direction with a electric dril , i have gotten oil pumps to start pumping again by doing this.

[Jerry Clark]

Re: No oil pressure!

Through the process of elimination this shouldn't be applicable, i.e. if it had pressure before the distributor were removed and doesn't now the distributor SHOULD be suspected but it certainly won't hurt to spin the pump with an alternate driver.

jerry

[Wayne Kever]

Oil's well that ends well

Got it back together correctly today. Got oil pressure, got no bad noises. Engine seems to have full power. I think I dodged the bullet. Thank God for an engine which sprang from an original splash-oiled design!

Thanks for the pointers.

The most enjoyable part was taking making a rod to oil the engine with the drill. Used a big wrecking bar to knock the handle off a cheap screwdriver. By that point, I had plenty of tension to let loose on that screwdriver.

- Wayne

[Greg Madden]

Re: Oil's well that ends well

I'd change the oil immediately, and in a couple hundred miles. You might want to get one of the oil analysis kits and send an oil sample in to be sure you don't have any metal in the oil. If you do, it's better to rebuild it before it fails in a big way. Good luck!

Regards,

- Greg

[Chuck G.]

Re: No oil pressure!

The 53-54 6 cylinder distributor has a separate vacuum advance/octane selector which slips around the distributor body. It is then clamped in place. The vacuum advance/octane selector also serves as the mount that holds the distributor in the block. If the vacuum advance isn't pushed up far enough, bottoming on the bottom of the distributor, it will allow the drive gear to engage, but the distributor will not be far enough into the block to engage the oil pump. This couldn't happen with a V8. It's one of the many "charms" of owning a 6 banger. Chuck