Grey stuff mixed in with oil??

[ynst]

Looks like a couple of tired engines I pulled apart years (decades) ago.

Both from the same customer who, religiously added STP to every oil change.

 

[PursuitSpecial]

It's more than likely not lead. Most quality leaded fuels contained dichlorethane or dibromoethane to form lead chloride or bromide salts which leave the engine with the exhaust to prevent this very problem with metallic lead fouling in the oil and plugs. Either someone burned lots of very poor quality leaded fuel, or it's simply moisture. I've taken apart many old engines that never burned anything but leaded gas and never got water in the engine, they had jet black sludge.

 

[James Romano]

It wasn't moisture. It was a light grey that didn't mix with the oil. It stayed separate and had the consistency of thick maple syrup. For a best visual...it looked like thick grey paint. When I posted picks of it in a thread a few years ago prior to this OPs thread...I got the same answer...lead. so if not lead, I'd love to know what it is and why it's in our motors.

 

[Sir Dodge alot]

It wasn't moisture. It was a light grey that didn't mix with the oil. It stayed separate and had the consistency of thick maple syrup. For a best visual...it looked like thick grey paint. When I posted picks of it in a thread a few years ago prior to this OPs thread...I got the same answer...lead. so if not lead, I'd love to know what it is and why it's in our motors.

The engine when I bought it was garaged, but the distributor was yanked out so there was a gaping hole right into the crankcase, there was a garbage bag stuffed into the distributor hole to "cover" it but I can assume water may have tricked in regardless of the bag.

 

[413]

When we say water in the engine we don't mean a flow of liquid. It can be moisture or condensation from a wet environment, and the engine not warmed up like a freeway trip to dry it out.

 

[Sir Dodge alot]

When we say water in the engine we don't mean a flow of liquid. It can be moisture or condensation from a wet environment, and the engine not warmed up like a freeway trip to dry it out.

Hello sir.

Condensation sounds like it, i picked up the engine from around Houston, TX.
Very humid so I can agree on condensation.

 

[James Romano]

When we say water in the engine we don't mean a flow of liquid. It can be moisture or condensation from a wet environment, and the engine not warmed up like a freeway trip to dry it out.

Definitely not the case for my motor...had the same material, as I stated above, in the same pockets in the engine. My motor has 86k+ on it and I run it. If I find the pics, I'll post them...but it definitely didn't look or feel like moisture of any kind.

Found them.... What's in the bag was what was in the bottom of the pan. If you say this moisture..ok...I'll buy it...because honestly...I still don't know what the crap is. I've never seen anything like it, and I've built a few motors in my lifetime of 55 years.

I just left it as "unknown grey matter" heavy and thick. Looks hazardous.

 

[SuperDave]

When water mixes with oil, it turns into creamy milkshake yellow or brown. I've nuked LOTS of motors (thanks to an oversized heavy right foot), and I've overheated many a motor in my hot rods; warped heads, blown head gaskets, cracked blocks/heads etc. I've also spent a good deal of time working in automotive machine shops, auto repair shops and auto salvage yards too. I have rebuilt hundreds of engines. Short of a chemical analysis, I'd bet a real honest dollar that gray sludge is bearing material and crank/cam/lifters/rings worn off, you did mention it felt gritty. Drop a magnet into the glop and see how much sludge it picks up and you will see for yourself.

It is also the biggest reason why I install a magnet oil drain plug in EVERY motor I own. All that trash circulating thru the motor in the oil is most likely why your bearings look the way they do.

Buy a magnet drain bolt, it'll double the life of your bearings and motor.

 

[Big_John]

It's more than likely not lead. Most quality leaded fuels contained dichlorethane or dibromoethane to form lead chloride or bromide salts which leave the engine with the exhaust to prevent this very problem with metallic lead fouling in the oil and plugs. Either someone burned lots of very poor quality leaded fuel, or it's simply moisture. I've taken apart many old engines that never burned anything but leaded gas and never got water in the engine, they had jet black sludge.

Definitely not the case for my motor...had the same material, as I stated above, in the same pockets in the engine. My motor has 86k+ on it and I run it. If I find the pics, I'll post them...but it definitely didn't look or feel like moisture of any kind.

Found them.... What's in the bag was what was in the bottom of the pan. If you say this moisture..ok...I'll buy it...because honestly...I still don't know what the crap is. I've never seen anything like it, and I've built a few motors in my lifetime of 55 years.

I just left it as "unknown grey matter" heavy and thick. Looks hazardous.

View attachment 723800

View attachment 723801

When water mixes with oil, it turns into creamy milkshake yellow or brown. I've nuked LOTS of motors (thanks to an oversized heavy right foot), and I've overheated many a motor in my hot rods; warped heads, blown head gaskets, cracked blocks/heads etc. I've also spent a good deal of time working in automotive machine shops, auto repair shops and auto salvage yards too. I have rebuilt hundreds of engines. Short of a chemical analysis, I'd bet a real honest dollar that gray sludge is bearing material and crank/cam/lifters/rings worn off, you did mention it felt gritty. Drop a magnet into the glop and see how much sludge it picks up and you will see for yourself.

It is also the biggest reason why I install a magnet oil drain plug in EVERY motor I own. All that trash circulating thru the motor in the oil is most likely why your bearings look the way they do.

Buy a magnet drain bolt, it'll double the life of your bearings and motor.

It's kind of funny, I've heard all of this except for the bearing material theory. I kind of like that one.

I think, like a lot of things, the leaded gas theory just came from a need to explain what it is. Probably, someone in the auto industry has actually analyzed what the goop really is and maybe it's out there somewhere on the intrawebs. Searching is going to give a lot of different answers though until you actually find a lab report.

Another theory I've heard was the gray sludge was due to additives like STP. I don't put a lot of stock in that one myself, but it's another theory.

I think we can all agree on a few things. First is it shows up a lot in older engines. It's probably a combination of factors that causes it and a lot of people have theories what it is. From there, we know that it's probably not real good to handle and you don't want to spread it on a cracker for lunch.

We can beat it to death about what it is, but really the answer is to just clean it out and move on to the next step.