Penetrating fluid test.

Frontstep

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A real corrosion nerd video testing various penetrants I will stick to atf and acetone for now.

 

Craiglxviii

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Now that IS interesting...

Shame he didn’t have any Plus Gas!
 

om613

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No. I can't listen to him any longer (at 20 seconds).
 

kid-jensen

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My experience with penetrating oils is that NONE of them get to where they need to go. Using perspex to demonstration purposes is all very well, but it doesn't emulate actual conditions where both nut and bolt will be rusting.

If a bolt is rusted solid such that you need to get brutal with it, the penetration oil won''t be able to get in there.

Obviously, once the bolt has moved initially any kind of thin oil will work, but that's not the marketing thrust that Penetrating oils are sold on.

All the above IMHO, obviously, but I've been spannering cars for nearly 50 years and this is the conclusion I've come to.
 

daveenty

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My experience with penetrating oils is that NONE of them get to where they need to go. Using perspex to demonstration purposes is all very well, but it doesn't emulate actual conditions where both nut and bolt will be rusting.

If a bolt is rusted solid such that you need to get brutal with it, the penetration oil won''t be able to get in there.

Obviously, once the bolt has moved initially any kind of thin oil will work, but that's not the marketing thrust that Penetrating oils are sold on.

All the above IMHO, obviously, but I've been spannering cars for nearly 50 years and this is the conclusion I've come to.


Agree with all of the above.

If it won't undo then either a substantial amount of heat to persuade it, or an angle grinder to eliminate it. Drastic the secondary approach may be, but it's certainly time saving in the grand scale of things.
 
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Frontstep

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Heat is when possible the best thing I have used, some penetrating fluids given long enough do make a difference.
A clout with the hammer can sometimes improve things.
What riles me is why some manufacturers still churn out rust magnets for safety critical components.
 

barnaclebill15

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Worst removal I had was in 1968 working in a power station, two of us got the job of changing 16 1" BSF studs in a steam valve of a main boiler. Another power station had the same valve cover blow off when the studs failed.
First we tried locking two nuts to unscrew using lots of penetrating oil, then we welded the nuts on the studs, then we cut the studs to just over 1" high and welded nuts on still no movement, finally we drilled 1/2" holes down each stud and filled them with welding hoping they would contract, they did but it still took a 16lb sledge hammer on a flogging ring all the way out, sure that the penetrating oil did nothing.
 

mercmancdi

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My experience with penetrating oils is that NONE of them get to where they need to go. Using perspex to demonstration purposes is all very well, but it doesn't emulate actual conditions where both nut and bolt will be rusting.

If a bolt is rusted solid such that you need to get brutal with it, the penetration oil won''t be able to get in there.

Obviously, once the bolt has moved initially any kind of thin oil will work, but that's not the marketing thrust that Penetrating oils are sold on.

All the above IMHO, obviously, but I've been spannering cars for nearly 50 years and this is the conclusion I've come to.

Agree the secret is in getting the first movement then being sensible with little oil working it in back and forth.
 

LostKiwi

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Do you s think impact wrench’s make life easier . As long as you don’t round the head
Yes.
Less chance of rounding the head of you use the correct impact socket (which will be a 6 point hex as opposed to the more usual 12 point). Biggest danger with impact wrenches is snapping the bolt/stud.
 

Westheath

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Coke/Pepsi is a myth but try telling those that have used it and believe it works lol.

Diesel, atf, light oils, heat cold, every squirty can brand under the sun promising freedom and release of the rusty stuff ........ sacrificing a chicken ....... been there got the T-shirt.

If it not coming out/undone its not coming out............

Drilling the bastige is my preferred method, but then this starts the discussion Colbalt Carbide Tungsten, even the little drill set once found in a Xmas cracker..........
 

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Xtractorfan

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A few mechanics have told me they use coke overnite on black death and then run the engine until it gets hot and the black death just scrapes off like toffee
 

Westheath

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Run the engine till its hot and it scrapes off anyway.

Not doing the Coke debate, been doing this sh*t too long to know what works and don't,
if someone thinks it worked then they couldn't have been trying hard enough the first time. imho

:)
 
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Frontstep

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Used Mr Muscle for black death on a warm engine worked for me oh and some carb cleaner finished it off nicely.
Lots of people use same stuff.

There are some more noxious chemicals that work well but they are not commonly available.
 

Westheath

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That's a cop out... is the earth flat in your world? ;)

Not a cop out just some common sense.

A 12 oz. can of cola with caffeine contains the most with 37 mg of phosphorus,
while the same size serving of diet cola with caffeine contains 32 mg.
Cream soda, ginger ale and root beer are all phosphorus free.
Milk and yogurt contain more phosphorus than soft drinks.
An 8 oz. serving of skim milk has 247 mg, and an 8 oz. serving of yogurt 385 mg.

https://www.livestrong.com/article/504049-the-phosphate-levels-of-soft-drinks/


I don't see any one pouring milk over their rusty nuts and bolts
or putting yogurt on seized injectors.








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