Hydrovac

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steveo916
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Re: Hydrovac

Post by steveo916 » Wed Sep 11, 2019 4:24 pm

a couple things that probably don't matter but.

I don't think copper lines are approved for brakes.
also there is some movement between the master cylinder and hydrovac and hydrovac to frame so the line should do a loop or jog this way and that to reduce line stress.
that is how the originals where and yours is likely to move more.
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Re: Hydrovac

Post by mkoloc » Wed Sep 11, 2019 5:15 pm

Steve, keeping it original, as that fits with the preservation project objective. I have been to several car shows in my area and have observed a number of vintage restored cars (Titled and Licensed) with copper lines.

Both lines coming from the Hydrovac have bends in them so I'm not quite sure what you mean. I'm curious as to why they would have rebuilt it this way in 52 if there is serious movement = failure? Brackets, mounts etc. are exactly as they were when rebuilt in.The intended brake line pressures are not that high, and the master cylinder isolates the brake pedal movement via its extensive linkage and three mounting bolts. I will keep an eye on it. I guess time will tell.

Jon, let me know if I can assist. Safe travels my friend!
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Re: Hydrovac

Post by Ben Dover » Wed Sep 11, 2019 5:30 pm

Do NOT use Copper tubing on brakes. It will not pass safety inspection. Should you have a brake failure accident you will be in big time trouble.
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Re: Hydrovac

Post by steve1973 » Thu Sep 12, 2019 12:12 am

The copper lines you are seeing on vehicles are actually steel lines with a copper coating to help against rust. Absolutely do not use actual copper lines. They are not rated for brake pressure. They are to soft.

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Re: Hydrovac

Post by mkoloc » Thu Sep 12, 2019 2:59 am

Well you have me convinced! I will,swap them out. Thank you for the info and advice.
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Re: Hydrovac

Post by yd328 » Thu Sep 12, 2019 5:29 am

The line you are seeing at the shows is most likely nickel-copper brake tubing. It is an approved material for brake lines that is easier to bend and has better corrosion resistance compared to steel tubing.

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Re: Hydrovac

Post by ph@5200 » Thu Sep 12, 2019 5:40 am

I have one of the earlier hydrovac on my halftrack (doesn't work) is it much of a job to change to the 3rd generation hydovac?

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Re: Hydrovac

Post by mkoloc » Thu Sep 12, 2019 2:59 pm

I think you would just have to modify your two brake lines and you might have to fab up a front mounting bracket which is simple to do, flat plate with a 90 degree bend. Seals for the WWII Hydrovac seem to be an issue, and the NOS rebuild kits are dried up and they cause problems when used (reading thru previous forum posts). My two cents.
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Re: Hydrovac

Post by steveo916 » Thu Sep 12, 2019 9:23 pm

when i did mine i was able to use the original front bracket with no modification.
i made the rear bracket from 1/4" plate.

http://halftrackinfo.com/index.php?acti ... 2070;image
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Re: Hydrovac

Post by spillmk1 » Fri Sep 13, 2019 3:54 am

yd328 wrote:
Thu Sep 12, 2019 5:29 am
The line you are seeing at the shows is most likely nickel-copper brake tubing. It is an approved material for brake lines that is easier to bend and has better corrosion resistance compared to steel tubing.

Gary
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Re: Hydrovac

Post by mkoloc » Fri Sep 13, 2019 8:40 am

Steve, did you mean front bracket fabrication? Rear brackets should have been the same as it is just a single hole bracket for back of Hydrovac.
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Re: Hydrovac

Post by steveo916 » Fri Sep 13, 2019 10:48 am

mark

your mounts are not original equipment. original where of similar size front and back
http://i165.photobucket.com/albums/u58/ ... 3748-1.jpg

I made my rear mount very rigid because any movement in the hydrovac would mean the brake lines are flexing which may lead to a break.
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Re: Hydrovac

Post by mkoloc » Fri Sep 13, 2019 2:46 pm

Thanks Steve ... Great pic of the original Hydrovac...tis all clear to me now, said the blind man!
LTC Mark Koloc USA (RET)
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1631 Bitter Creek Lane
Batavia, OH 45103
Cell: 1.715.821.9426

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