What is going on with these rod bearings?

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TylerW

TylerW

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Hey guys:
I'm going through a fairly low mileage engine to go in my Scamp, and found something disquieting. By low mileage, I mean an unrebuilt 1970 engine with under 100K.

Here's one of the rod bearings. What is going on here? The inserts aren't excessively worn or smeared, but they all have this pockmarked appearance. I had hoped to gasket and paint this thing and stab it in but I don't like the looks of this. The crank journals look good. A couple have some marking but not enough to catch a fingernail. I will measure the clearance with these original bearings to get a baseline.

Thanks.

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infrequent oil changes//chemical erosion??
 
Moisture in the oil, and extended periods of doing nothing. Think galvanic cell.
 
Old bearings,lead...and decades of moisture in the oil... oil floats to the top....the first time its fired after LONG periods of sitting in weather cycled/condensation...and it's more water than oil that goes through initially.

They say it's good to start and run them once a week for 20 min for a reason.
Garage kept helps, some... but tits mostly the temp/moisture.
 
You confused me at "disquieting".

I thought it was a mistake. I was wrong. This is a real word:

Dictionary
dis·qui·et·ing
/disˈkwīədiNG
adjective
  1. inducing feelings of anxiety or worry.
    "he found Jean's gaze disquieting"
I've torn down a few original engines and have seen the same thing. I attributed it to water/acids in the oil from condensation.
 
Something MORE disquieting, will be the condition on the cam bearings. They're just as old and even more susceptible to deterioration.
 
MOPAROFFICIAL said:
Old bearings,lead...and decades of moisture in the oil... oil floats to the top....the first time its fired after LONG periods of sitting in weather cycled/condensation...and it's more water than oil that goes through initially.

They say it's good to start and run them once a week for 20 min for a reason.
Garage kept helps,... but tits mostly the temp/moisture.
Click to expand...

‘but tits mostly’
Can’t disagree with that.
 
@RustyRatRod

Why are some people total numb skulls?
I say If you don't have a motor in a temp controlled environment...over many years it rusts, and the oil is corrupted...
Some fkrs think I'm full of ****, okay..lol
 
@RustyRatRod as if these sacks of scum havent torn an oldie apart and seen the ring marks in the bores where they sat forever.

Yeah it's all hogwash ,piss in a bucket.

Run it with water and mud
 
MOPAROFFICIAL said:
@RustyRatRod

Why are some people total numb skulls?
I say If you don't have a motor in a temp controlled environment...over many years it rusts, and the oil is corrupted...
Some fkrs think I'm full of ****, okay..lol
Click to expand...
Right. That's why you always heard growin up short trips were killers, and it's true. My auto shop instructor used to always stress if you're going to use a car, make sure you drive it regularly and drive it at least 20-25 miles once a week IF all you did were short trips. At least that way, it would get up to a solid enough temp to get all the moisture and crap out of the oil and keep everything lubed. Sitting up and short trips is what kills everything. From bearings to rings and even seals. I've let Vixen sit for a little longer than I really like to. Haven't driven her in over a week. But when I do, you can bet it'll be at least 25-30 miles. Course that's normal for us anyway, since we live about 30 minutes from anywhere around here. lol
 
RustyRatRod said:
Right. That's why you always heard growin up short trips were killers, and it's true. My auto shop instructor used to always stress if you're going to use a car, make sure you drive it regularly and drive it at least 20-25 miles once a week IF all you did were short trips. At least that way, it would get up to a solid enough temp to get all the moisture and crap out of the oil and keep everything lubed. Sitting up and short trips is what kills everything. From bearings to rings and even seals. I've let Vixen sit for a little longer than I really like to. Haven't driven her in over a week. But when I do, you can bet it'll be at least 25-30 miles. Course that's normal for us anyway, since we live about 30 minutes from anywhere around here. lol
Click to expand...
Absolutely. Heat the moisture out of the oil.
 
MOPAROFFICIAL said:
@RustyRatRod as if these sacks of scum havent torn an oldie apart and seen the ring marks in the bores where they sat forever.

Yeah it's all hogwash ,piss in a bucket.

Run it with water and mud
Click to expand...
LOL. They'll freeze and pit right to the cylinder walls if they sit up too long. Those are the ones you can never get to stop smoking, because they are stuck, but not stuck enough the starter won't turn them and when they do turn them they tear the coating right off that top ring. Over and done. You gotta drive um.
 
RustyRatRod said:
LOL. They'll freeze and pit right to the cylinder walls if they sit up too long. Those are the ones you can never get to stop smoking, because they are stuck, but not stuck enough the starter won't turn them and when they do turn them they tear the coating right off that top ring. Over and done. You gotta drive um.
Click to expand...
My shop teacher said if you were to build and fire up a motor and let run.. never shutting it off..that it would run a lifetime. Figure changing oil in there somehow...lol but he was right.
 
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RustyRatRod said:
LOL. They'll freeze and pit right to the cylinder walls if they sit up too long. Those are the ones you can never get to stop smoking, because they are stuck, but not stuck enough the starter won't turn them and when they do turn them they tear the coating right off that top ring. Over and done. You gotta drive um.
Click to expand...
Am I starting to get Paranoid about Piston Slap noise, cause my car sat for years, after the ex wrecked it?
 
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