brake fluid flush

1959 - 1978, M151, M151A1, M151A2, Technical questions and discussions, regarding anything related to the M151.
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ldj1002
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brake fluid flush

Post by ldj1002 » Fri Apr 01, 2022 1:38 pm

I am working om brakes. Old fluid doesn't smell like DOT3. What should I flush it all out with. Going to put DOT3 in. Oh just found one more problem. Wheel cylinder threads are striped where bleed screw goes in. Any fix other than new wheel cylinder?


Rickf
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Re: brake fluid flush

Post by Rickf » Fri Apr 01, 2022 4:30 pm

Well, To flush out the wheel cylinders you have to remove at least one of the cups so if you are that far into it why not just replace them all? They are not that expensive and if the system has never been serviced I will bet they are full of rust. Especially if it had DOT 5 in it. You can find replacement bleeders but first you have to get the bad ones out and if they are rusted in there they probably will break off. How much time and effort do you want to put into them? Just replace them with new and you will not have to worry about them for a long, long time.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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W. Winget
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Re: brake fluid flush

Post by W. Winget » Fri Apr 01, 2022 5:45 pm

The military switched to DOT 5 sometime in the 80's from memory, so if you have an A2 MUTT, it likely had Silicone fluid in it during its service.
A gallon usually sells at a show for around $60 from what I bought last year...if you buy it by the pint, expect to pay 10-20 at a store.
You can switch back to DOT 3 if you are doing the wheel cylinders anyway but should flush it every few years if you do this.
V/R W. Winget
Looking for 1918 Standard B 'Liberty' truck parts

Fil Bonica
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Re: brake fluid flush

Post by Fil Bonica » Sat Apr 02, 2022 7:25 am

If it were my Jeep I would flush and refill with Dot 5.
While costly it is more durable and does not absorb moisture like Dot 3.
Years ago had to do emergency repairs on my A2 brakes.
The system was cleaned and flushed with no signs of rust or corrosion . The rubber components were all fine.
Much better than having to bleed dot 3 every few years in order to clear the rust and grunge.
In my mind the benefit outweighs it additional cost
Have a copy of the military study advocating its use if anyone wants to read.
.
Fil Bonica

svramselaar
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Re: brake fluid flush

Post by svramselaar » Mon Apr 04, 2022 1:25 am

hi
to begin
put a litle old fluid at a glas water if it seperate it is silicone if it mix it is normal dot 3-4

i use silicone for i think 25 years now never had a cylinder leaking or stuck :D
1976 ? M 151 A2 AMG MUTT lost in acsedent
1978 M 416 A1 ( parkhurst ) trailer
1970 m151 A2 FORD BUDD tub
1957 Volvo sugga radio truck
M 274 mule HOME MADE MULE


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