When you can hear the oil pump clacking in time with the engine...

[None_zero]

How long would you guesstimate the oil pump might continue functioning when you can hear a very noticeable clacking coming from it?

[None_zero]

Shouldn't hurt if I topped off the oil with some 5w 30 for gasoline engines into the 10w 30 for diesel engines that I'm running in it right? Oil be a little thinner but the only difference is extra detergents right?

[None_zero]

Oh brand new symptom just now started hearing a high pitched squealing that's almost like a belt squeal but it has a really rapid warble to it Ns I've never heard the belt sound that way. Usually if the belt squeals it's much louder and lacks that rapid warble 

[datzenmike]

Oil pumps don't wear out. They OIL pumps.

 

I wouldn't run 5W anything unless desperately low and nothing else around, then replace with correct 10w30. 1 quart won't hurt.

 

Gas engine oil is very low in ZDDP, about 500-600 PPM. Diesel oils like Rotella T4 are 1,200 PPM ZDDP.

 

Loosen fan belts including power steering (PS) and AC if equipped and run the engine. This will eliminate the alternator, water pump, clutch fan and bearing, PS pump and AC compressor as well as a squeaky belt and the bearings in the PS and Air Con adjusting pulleys. Sound gone???

 

[None_zero]

I'll try fiddling with the belt but I really don't think that's it. The sound seems to be coming directly from the oilpump and I don't have power steering or ac could be the water pump or main pulley I suppose I'll let you know what I discover 

[datzenmike]

The alternator is just above it.

[None_zero]

I hear it much more distinctly from below rhe engine than from above though 

[Crashtd420]

You could remove the belt and run the engine for a minute to rule out the alternator and water pump....

[datzenmike]

Noise is almost always timing chain guide wear. On top likely valve clearance sometimes an exhaust leak.

 

Squealing is most likely the fan belt.

 

If you've had an oil pump apart there's not much that can clack inside.

[Stoffregen Motorsports]

If an oil pump got metal in it at any point in its life, it could have a scar on it and could make a noise. It's more likely something behind the timing cover. A worn chaintensioner plunger, a bad distributor drive gear, loose crank pulley bolt, or even a worn timing chain which is rubbing on the oiler.

[datzenmike]

If the head has ever been off by a novice and the chain tensioner unknowingly popped out it will run but it's very likely to make noise. People have also pulled the timing cover off to replace the chain and found a worn oily chunk of wood in there from the wedge. It ran fine though.

[Stoffregen Motorsports]

It is possible that these engines are getting so old that things are starting to wear that you wouldn't expect. I'm thinking of the timing cover where the distributor drive spindle spins. If it has wear on the underside, it could allow the spindle to jump up and down. I have shimmed this in the past, like on a race motor that's running a distributor (not crank trigger) and we needed the timing to be spot on. Wear after 50 years could be bad enough to require shims.

[datzenmike]

I may be wrong but the Dime Quarterly had a way to remove the spindle/distributor slop by bending an aluminum pull tab, bending and setting it on the top of the spindle, then installing the distributor. It would crush into shape and prevent the timing wander at all RPMs.