Let’s talk oil sludge/model A

[DCIV]

I joined a Facebook group when I knew I was getting the model A. Since then it’s full of people getting their model A’s running. Most after sitting. Almost all talk about the oil turning to sludge and a fair amount talk about how the main bearings being wiped out because of said sludge blocking the passages.

How do I clean it out, without taking this thing all the way apart?


Coop

[Jeff V.]

Do it right or do it twice.

If you're that worried about it, strip it down. I've only ever seen these things in pictures, so I could be very wrong. But it looks like it would come apart a lot easier than a modern car.

[ChargerX3]

I wouldn’t overthink it. That motor is super simple. Just check the consistency on the dip stick. Dump it and put in some new oil. Ideally use some specialized oil with ZDDP for your flat tappet cams. Nice thing about modern oils is they have proper amounts of detergents to help clean up deposits over time.

You can also run a quart of trans fluid or motor flush before oil changes. Those just speed up the process.

[DCIV]

[quote=""Jeff V.""]Do it right or do it twice.

If you're that worried about it, strip it down. I've only ever seen these things in pictures, so I could be very wrong. But it looks like it would come apart a lot easier than a modern car.[/quote]

I agree. It’s easier than modern. I’m sure very well documented. But I was hoping for two things one, I don’t wanna ruin the look of it. And two, surely there is anyway to flush it? Can’t I put something in the oil, turn the oil pump over by hand someway? Like they do with the drill in a distributer?


Coop

[Jeff V.]

Maybe. But then you have to worry about getting the cleaning solution completely out of the engine so it doesn't screw up your oil.

[ChargerX3]

I don't know about model A's but on Mopars you can put a hex chuck down the distributor to prime the oil pump.

When i went to start my 67 Charger for the first time in 20 years I didn't even do that. Sprayed a little WD40 in the intake manifold and cranked her over. Then switched to gasoline.

You are overthinking this.

[Jeff V.]

When was the last time this thing was run, and for how long? Are these guys talking about cars that have sat around for 5 years with modern oil, or 90 years with whatever sludge passed for oil in the late 20s?

[DCIV]

Last time it was run was 60yrs ago. Most the people I see talk about it are talking 15-30yrs ago. One of the guys on the Facebook group suggested kerosine for 5 mins then let sit overnight. Gah that goes against everything that feels right.


Coop

[aaronatstate]

Kerosene is basically cleaner diesel fuel. (Kerosene is the same as Jet fuel basically).

I think it's not uncommon to use diesel/kerosene in your crank case to clean it out...

[Jeff V.]

60 years. Ok....you may have a point with this one.

[ChargerX3]

[quote=""aaronatstate""]Kerosene is basically cleaner diesel fuel. (Kerosene is the same as Jet fuel basically).

I think it's not uncommon to use diesel/kerosene in your crank case to clean it out...[/quote]

Yea, Motor Flush is essentially Diesel. It does a great job cleaning while offering a small amount of lubrication.

Pull the oil drain and see what comes out. If its consistency is tar then you might need to dig deeper. If its liquid then I wouldn't worry.