ANTI-FREEZE & ENGINE BEARINGS

Boxcars

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Sep 4, 2004
Just a trivial question I'm not sure about. Fortunately for me, I've never had a blown head gasket that resulted in filling my crank case with water or anti-freeze. I'm under the impression that if this happens, a blown head gasket, and you have anti-freeze in your cooling system, you will have to change out your engine bearings because the anti-freeze eats bearings. I didn't want to have to change out my bearings because of a blown head gasket that floods my crankcase, so I never run anti-freeze. Now, maybe running straight water doesn't make any difference. Does anybody know, have comments, or suggestions?

My second quetion would be, if it's only the anti-freeze that eats bearings, and by running just water I can avoid bearing damage -- if that is true, is their any additive I can put in the water to stop it from getting rusty, not a big problem because I flush it out with clean water every couple months or so, but still not damage engine bearings in the event of a blown head-gasket.
 
Most blown head gaskets don't end up with water in the oil on these cars but I had a set of the famous champion aluminum heads that cracked and they caused antifreeze to mix with my oil. I've never run antifreeze in a turbo buick engine since that expensive learning experience. I use the RMI-25 and it works very well but I'm also in Florida so it rarely freezes here.


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Thanks Jerry. There was only this in the thread:

Biggest downside for antifreeze is if it gets to the engine bearings due to a blown headgasket the bearings are usually toast. The water and RMI-25 is not usually an issue. I don't run antifreeze in the GN or the racecar because a headgasket is easy to fix. Rebuilding the engine isn't quite as easy. My opinion but I have never seen the need for antifreeze.

Now, this is just one opinion. Maybe he never blew a head gasket with RMI25. I am familiar with it, but never used it. Sounds like a good product for keeping the coolant system clean, but, does it damage engine bearings or not? That is the question.
 
Most blown head gaskets don't end up with water in the oil on these cars but I had a set of the famous champion aluminum heads that cracked and they caused antifreeze to mix with my oil. I've never run antifreeze in a turbo buick engine since that expensive learning experience. I use the RM-125 and it works very well but I'm also in Florida so it rarely freezes here.


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Yes, I've had those "dry" head gasket failures. :confused: But again, do you know for sure, or have you come to understand by comments of others, that RM125 doesn't damage engine bearings?

By the way, how much do you need to use?
 
Thanks Jerry. There was only this in the thread:

Biggest downside for antifreeze is if it gets to the engine bearings due to a blown headgasket the bearings are usually toast. The water and RMI-25 is not usually an issue. I don't run antifreeze in the GN or the racecar because a headgasket is easy to fix. Rebuilding the engine isn't quite as easy. My opinion but I have never seen the need for antifreeze.

Now, this is just one opinion. Maybe he never blew a head gasket with RMI25. I am familiar with it, but never used it. Sounds like a good product for keeping the coolant system clean, but, does it damage engine bearings or not? That is the question.

A HG may be easy to fix for those who done have the AC box in the car, such as a race car. Obviously, a blown HG is typically only a matter of time if the engine is pushed, but , repeated blown HG point to a different issue. It really is not as simple as it sounds if done correctly (Resurface heads, manifold alignment, pushrod length, CR increase and retuning, etc, etc.)

Anything that diminishes lubrication properties will cause engine failure, IF, run for an "extended" period.
The definition of "Extended" varies greatly because it all depends on the contamination volume/media, and operating conditions.

If the concern is with leaking coolant due to a leak, and consequent bearing damage, run distilled water and RMI25. That will provide the best option. This doesn't mean or imply engine damage will not occur though.

Pending mechanical condition of the coolant system, you should also expect a 6-10F drop in temp., if the temp is rising in that range above the thermostat. That's not a opinion.

Hope that helps.
 
I had oil that looked like coffee with a ton of milk added. I had steam coming out of the breathers. Drove it 20 miles or so with it like that back home and never changed the bearings until I upgraded the engine years later.
 
I had oil that looked like coffee with a ton of milk added. I had steam coming out of the breathers. Drove it 20 miles or so with it like that back home and never changed the bearings until I upgraded the engine years later.

Were you running anti - freeze? If you were, then I'd think that the cautions on anti-freeze is much to do about nothing?
 
Antifreeze yes, I don't know if there would be a difference but I should have mentioned this was with a BBC not a LC2.
 
Antifreeze yes, I don't know if there would be a difference but I should have mentioned this was with a BBC not a LC2.

OK. There might be a difference, though. A small engine therefore much smaller bearings that may be making the same horsepower as a BBC. Maybe someone else will chime in. It's not real important, but it's just something worth knowing.
 
So, just by putting in 8oz. the coolant stays clear? What's has been your experience?
No, it won't be clear. The product itself is fluorescent green. Once diluted with water it simply becomes a watered down fluorecent green.
 
Why would straight water be better than antifreeze? Antifreeze at least has some lubrication qualities and a higher boiling point.
 
If your running a flat tappet cam I would be more worried about that than the bearings.

Why would straight water be better than antifreeze? Antifreeze at least has some lubrication qualities and a higher boiling point.


Well, according to some people, anti-freeze in the crank case damages the bearings. I don't need anti-freeze, so I don't use it. One thing is for sure, and it's what I got out of this whole thread. If you don't blow a head gasket, you don't have to think about it. :eek:

Exactly what I knew before started this thread.
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