Unstuck

[FF]

Had a brew with a friend that had done lots of Outboard engine work (40 years worth) and we discussed unsticking an engine.

His choice was auto Brake Fluid!

His stated ATF or diesel (my favorite) is a great at penetrating , but did nothing to the rust,.

His claim was std car brake fluid will soften the rust in a couple of weeks , and perhaps save a complete tear down .

Anyone ever heard of this???

 

[rardoin]

Hmmmm....Brake fluid of DOT 3,4 and 5.1 will imbibe water and increase corrosion on exposed mild steels in my experience. Silicon based DOT 5, which I used in auto racing applications is not hygroscopic. I would think the hygroscopic fluids left in contact with a steel cylinder liner would make the problem worse. Then again...in theory only...I've never tried what your mechanic has suggested and I am not a professional mechanic.

 

[Capt.Bill11]

“Machinist Workshop Magazine” did a test of penitrating oils.

"Using nuts and bolts that they ‘scientifically rusted’ to a uniform degree by soaking in salt water, they then
tested the break-out torque required to loosen the nuts. They treated the nuts with a variety
of penetrants and measured the torque required to loosen them.

This is what they came up with:
Nothing: 516 lbs
WD-40: 238 lbs;
PB Blaster: 214 lbs;
Liquid Wrench: 127 lbs,
Kano Kroil: 106 lbs
(ATF)/Acetone mix (50/50): 50 lbs."

So tell your friend to get some ATF and acetone next time.

 

[psneeld]

Good one FF.....

Not sure about the water issue...can't remeber ever having a steel brake line rust from the inside out.

Brake fluid is tough on paint where other fluids arent as quick it seems.....wonder what's inside that softens paint? The MSDS has stuff that I don't recognize to react with rust specifically so maybe someone with experience with brake fluid chemistry can help.

 

[psneeld]

“Machinist Workshop Magazine” did a test of penitrating oils.

"Using nuts and bolts that they ‘scientifically rusted’ to a uniform degree by soaking in salt water, they then
tested the break-out torque required to loosen the nuts. They treated the nuts with a variety
of penetrants and measured the torque required to loosen them.

This is what they came up with:
Nothing: 516 lbs
WD-40: 238 lbs;
PB Blaster: 214 lbs;
Liquid Wrench: 127 lbs,
Kano Kroil: 106 lbs
(ATF)/Acetone mix (50/50): 50 lbs."

So tell your friend to get some ATF and acetone next time.

Most useful post of the day so far....at least for me

 

[kulas44]

This post is very interesting, especially since as of this morning I used up a large part of my time hosing the cylinders on a Honda 200 hp outboard with PB Blaster. I dont neccessarily prefer it and would rather use ATF/acetone but just didnt have any made up right now. I had never thought of using brake fluid, but I will give it a try next time. I have used DMSO mixed with ATF, now that is a real penetrating fluid. If it gets on your skin you will taste the ATF in a few minutes. Nasty and dangerous stuff, but will go thru rust every time. BTW, I finally got the engine to turn.

 

[capt jerry]

Had a brew with a friend that had done lots of Outboard engine work (40 years worth) and we discussed unsticking an engine.

His choice was auto Brake Fluid!

His stated ATF or diesel (my favorite) is a great at penetrating , but did nothing to the rust,.

His claim was std car brake fluid will soften the rust in a couple of weeks , and perhaps save a complete tear down .

Anyone ever heard of this???

when i was a kid working in a junk yard,we used gun barrel cleaner it worked all the time,

 

[Deckape]

Had a inboard engine overheat and got water into the cyninders and locked up. Took plugs out and poured atf into each cyninder. Tuned crank each day till moved freely. Put new gasket on and run that engine for years.