Bad Oil Pump Clicking??

[IBFJ62]

I've been bashing my head on the bench trying to find the source of a mysterious 'click' (or clack) in the engine. I've assumed it was in the valve train, but everything seems to be in spec and fine. I was hoping a needed new set of cats and a muffler might solve it, but no such luck.

With the stethoscope poker, I can hear the click echoing in the engine from sort of all over, but it gets more distinct and louder at the base of the distributor. It also varies in synch with rpm increase. It has a certain pattern to the sound that makes me think it's the oil pump slapping back and forth. Is that possible?

I thought it might be the crank just nicking the oil pump so I pulled the pan, and all looked fine through the rotation. I did notice that there is a little play in the gear on the distributor, and also in the interface of the distributor and the oil pump where it stabs in. The play also created a click, which got to me to think maybe the teeth in the dist. gear are worn? But I can't really see how it would make a rhythmic clacking. The cam is new from a rebuild about 3 years ago. dist. is original.

Ideas? Suggestions? Thanks.

 

[pithicus]

Apart from the distributor not being properly seated, I have no idea. Can you try a different distributor?
The dist rotor would show a bit of slop if it was badly worn, but shouldn't create an audible knock.

 

[Cnut]

I'm going to a muffler shop to check for an exhaust leak for a similar-sounding click.

 

[IBFJ62]

Been there, done that. Unfortunately no luck there. Sounds great, other than the clacking..

 

[OSS]

The oil pump is such a sturdy and simple device. Just two gears spinning while submerged in oil.

Although the sound -could- be from the oil pump, my guess is there's nothing wrong with it. They last forever.

 

[Prairie Swamp]

This is a 3FE correct? I recently had my oil pan to bits and I distorted the windage tray somehow. Got the pan back on and had a knock from hell. The crank counterbalance (I think) was hitting a corner of the windage tray right near the oil pump. Don't know how your windage tray would have gotten tweaked but just a data point. The clearance must be really close though.

I had the disty out to spin the pump to prime the motor. I was surprised how much torque (via drill) it took to spin the oil pump. So I don't really know how it could oscillate or pulse to cause a tick against the disty drive. Unless your timing gears are ragged out? But then I would think it would run horrible?

Weird.

 

[IBFJ62]

It is a 3FE, and I agree, it seems that it would be tough to cause the pump to clack the way it is, but I'm stumped. Maybe the crank is nicking the pan, I thought that might be a suspect as well, but sticking the scope on the pan didn't sound like an obvious source. I'll scope it again, and try to narrow it down further, but it's making me crazy. An engine that otherwise runs perfect sounds like crap..

 

[SteveH]

Pull the distributor, and run the oil pump with a (beefy) electric drill. I think it runs CCW. Listen for the clicking.

Cut off a screwdriver end of the correct size and chuck this up in the drill as a driver for the oil pump. My half-inch corded drill was working hard to turn the oil pump....

 

[IBFJ62]

Question. Would it be possible to install the oil pump mount upside down? And doing so, perhaps alter the distance the distributor shaft interfaces with the receiving shaft on the oil pump??

 

[IBFJ62]

Ok, I was just going through the Specter catalog and diagrams, and I see an 'Oil Pump Compression Sleeve' (PN 034-81A-A). When I pulled the distributor and oil pump, I did not have one of these... Where does that go??