Grit in motor oil

pdora

pdora

Senior Member
I friend recently bought a 1929 roadster. It had not run for a long time, but the previous owner got it going and my friend drove it home.
The first thing we did was change out the fluids.

When we released the oil I noticed a gritty substance on the inside of the drain plug. It had the feel of beach sand slathered in motor oil.

I assume the particles were metallic, but did not have the chance to investigate further.

The motor appears to be stock and it starts right up, runs well and seems to have expected pickup.

Any observations? Could this be babbit material?

Thanks.
 
Pete, It does not sound like babbit to me. Usually babbit in pan will look like broken up gray egg shells. My first thought would be to drop the pan, investigate, clean out pan baffle whereas grit may be still built up in the rod dipper wells in the pan baffle. Flush through with some cheaper oil, since you have pan off, I would simply remove oil pump and go through that too. Babbit is non-magnetic too. If you found only a little bit of grit only on the drain plug, I wouldn't worry, This is common on old cars that never had an air filter or oil filter. Try poking your little finger up and around the open oil drain plug hole in bottom of pan.See what you find.---Best, Pete.
 
Pete,
Purdy is onto something in his evaluation. The longer it sat unused, the more likely that the condensation/acid that sat on unused metal 'grew' rust particles that flaked off.
You didn't say, when you drained the oil, what condition it appeared to be in, i.e.- black as coal/thick as syrup/small volume..what? One quick way to determine nature of the crud....take a magnet to it,eh ! Babbitt won't/rust will....
 
Carbon? You should drop the pan and remove the valve cover. I suspect you will find more. After through cleaning, include clearing the oil channels from the valve cover area down to the cam and to the mains. Also remove and disassemble the oil pump. Bob
 
If the previous owner used a conventional antifreeze with leak-stop additives based on silicic acid (eg. Prestone) and this got into the crankcase, your reference to beach sand could be spot on. That is why many folks prefer straight water or the propylene glycol based antifreeze products. I would drain the coolant and pull the pan before hitting the starter button again.
 
Wow, seven responses and seven different answers!

This is fairly common in old cars regardless of use. Most of the time it's nothing to worry about as it's a build up of carbon that can occur throughout the interior of the engine. Sure you could drop the pan, pull the valve cover and other parts to clean things, but this will only get a portion of things. It could be rust on the inside of the oil pan, but running the engine helps to control future damage caused by that.

You could treat it like a modern car. Do you suddenly have grave concern during a routine oil change when you see the gray material that accumulates on the magnetic drain plug? The old saying of "if it ain't broke, don't fix it" is appropriate here. Drive and enjoy it!
 
Could be sand and dust being injested into the pan. The pan is designed to catch those particles and let them drop to the bottom. If it felt like dirt it's probably what settled out and it won't be likely that it will climb back up through the dipper tray and get in the bearings. Frequent oil changes are recommended. I change my oil every 500 to 1000 miles.
 
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I once bought a running chassis and got it home and ran the engine for a few minutes before I disassembled the entire car for parts. It ran nice and quiet,no leaks. When I pulled the pan it was filled to the dipper tray with a grey gritty sludge with the consistency of thick mud. Surprised it ran at all.....I would pull the pan and see what is under the dipper tray....
 
First time I changed the oil on mine, I had the same experience. Reminded me of the Castrol ad with the guying getting "sludged" Driving and normal changes with detergent oil and its been fine, I think it was just old oil and settled crud.
 
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