Author Topic: Aftermarket hydrovac - which is best?  (Read 1441 times)

8683jb

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Aftermarket hydrovac - which is best?
« on: February 15, 2018, 06:55:16 PM »
I rebuilt my hydrovac a few months ago with an NOS kit and it worked fine until the other day when I stepped on the brake pedal and it went to the floor. The master cylinder is empty and no visible fluid leaks anywhere, so I’m assuming it’s gone into the hydrovac unit from the slave cylinder. I had read a few posts some time back discussing various aftermarket hydrovac units. Was there any consensus on which was the best? I'd rather keep the original but if I'm gonna be chasing my tail with it, I’m thinking about upgrading to a modern unit if it's not too much of a headache to fit it. Thanks.

Jon
'42 Autocar M2A1

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spec4don

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Re: Aftermarket hydrovac - which is best?
« Reply #1 on: February 15, 2018, 08:36:48 PM »
Yep I did the same thing! There is one little seal that goes bad! I’ll send mine out to be professionally rebuilt next time. My next halftrack will have a newer hydrovac

Don G
1941 M2A1 not restored
1942 M3 Diamond T Mostly restored
1943 M3A1 Under restoration
1967 M51A2 Tractor
1945 WC 63 needs restoration
1967 M36 Long wheel base duece
1951 M135 GMC Fire truck conversion

8683jb

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Re: Aftermarket hydrovac - which is best?
« Reply #2 on: February 15, 2018, 10:07:38 PM »
Which seal is it Don? I read about a seal that's unobtainable, but the kit had new cup seals and new leather packing in the guide. What's left? I wonder if the low-pressure fluid's getting past the piston and into the diaphragm chamber and then drawn into the hydrovac?
« Last Edit: February 15, 2018, 10:10:41 PM by 8683jb »
'42 Autocar M2A1

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woodwalker

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Re: Aftermarket hydrovac - which is best?
« Reply #3 on: February 16, 2018, 07:28:20 AM »
Chevy 1.5 tonn . Not a exact match but it works. Contact
Col.halftrack

8683jb

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Re: Aftermarket hydrovac - which is best?
« Reply #4 on: February 16, 2018, 08:40:35 AM »
I'll check into that one. Thanks woodwalker.
« Last Edit: February 16, 2018, 08:49:20 AM by 8683jb »
'42 Autocar M2A1

MVPA member