Halftrack vacum booster

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emptyhead2
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Halftrack vacum booster

Post by emptyhead2 » Fri Apr 15, 2022 5:06 am

Posting here and on halftrack info. Before I run my 3rd vacum booster in 18 months out to a different company I’ll ask I one more time and maybe someone has some answers. I’m running the 51-8030 cardone vac booster, had diaphragm and seals let go on the first two and got 5 miles on #3 and brake are sticking with a really stiff pedal. Am I missing something else somewhere in the system. Installed all new wheel cylinders a couple of years ago. Master cylinder was rebuild again, loosen the line after sitting two days from the out side of the booster and still was under pressure. Will run it in the neighborhood with just the master cylinder to see if the brake are sticking. Any advice is welcome. All three are cardone rebuilds. Thanks


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Re: Halftrack vacum booster

Post by 8683jb » Fri Apr 15, 2022 6:52 am

Mine were dragging with a hard pedal and I immediately blamed the hydro-vac because of its track record. It turned out to be the master cylinder (rebuilt). I replaced it with new master cylinder and it's been fine ever since. You might confirm your rebuilt one isn't the culprit before you pull the hydro-vac again. Good luck.
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emptyhead2
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Re: Halftrack vacum booster

Post by emptyhead2 » Fri Apr 15, 2022 8:15 am

Thanks for the reply. I’ve tried the Wagner master cylinder and the newer raybestos cylinder so I don’t know.thanks

emptyhead2
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Re: Halftrack vacum booster

Post by emptyhead2 » Fri Apr 15, 2022 10:00 am

Just ran it for about 20 minutes with just the master cylinder and no dragging the drums where pretty cool to the touch. In the past the drums would have been to hot to touch.

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Re: Halftrack vacum booster

Post by Bradym114 » Mon Apr 18, 2022 5:17 am

I'm tired of fighting mine so I'm just getting rid of it. The manual brakes should stop it fine otherwise ill have the hand brake for backup. it's not like they are on wheels they don't free roll easily plus they aren't at combat weight.

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Re: Halftrack vacum booster

Post by jesse » Mon Apr 18, 2022 5:56 am

Halftracks are not safe to drive without a booster. Takes way too long to stop with just a master cylinder. Using the parking brake at speed will as likely as not snap the rear input shaft. Brand new reliable type C boosters can be had for a few hundred dollars and work great.

Bradym114
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Re: Halftrack vacum booster

Post by Bradym114 » Mon Apr 18, 2022 8:00 am

jesse wrote:
Mon Apr 18, 2022 5:56 am
Halftracks are not safe to drive without a booster. Takes way too long to stop with just a master cylinder. Using the parking brake at speed will as likely as not snap the rear input shaft. Brand new reliable type C boosters can be had for a few hundred dollars and work great.
Yes they are, it's not like these things go 70mph. There were tons of highway trucks without boosters, and they stopped just fine. Mine for the last five years hasn't had brakes other than the parking brake and it stopped just fine with only that. Guess I've just been lucky.

Now i am in a fairly rural area, so the stopping distance is less important. Probably would want the extra brakes in a city.

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Re: Halftrack vacum booster

Post by Ron D » Mon Apr 18, 2022 9:02 am

If you get involved in an accident and an investigation uncovers that your brakes weren't installed or operating correctly, then I imagine things could get real expensive very fast? Double that if you knew it when you started the motor. Through the roof if you injure or kill somebody.
And really crazy-stupid money if somebody discovers social media posts (like this one) about driving with defective brakes.

Is taking short-cuts with brakes really worth it?

Pretty sure It doesn't take much speed to total cars on the road today. Especially with the mass of an All-American steel halftrack.

I'd rather share the road with vehicles that have properly operating brakes (and of course, drivers that pay attention to safe driving).
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emptyhead2
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Re: Halftrack vacum booster

Post by emptyhead2 » Mon Apr 18, 2022 12:58 pm

Thank you guys for posting I’ll continue to try and pin it down.

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Re: Halftrack vacum booster

Post by Bradym114 » Mon Apr 18, 2022 1:37 pm

Ron D wrote:
Mon Apr 18, 2022 9:02 am
If you get involved in an accident and an investigation uncovers that your brakes weren't installed or operating correctly, then I imagine things could get real expensive very fast? Double that if you knew it when you started the motor. Through the roof if you injure or kill somebody.
And really crazy-stupid money if somebody discovers social media posts (like this one) about driving with defective brakes.

Is taking short-cuts with brakes really worth it?

Pretty sure It doesn't take much speed to total cars on the road today. Especially with the mass of an All-American steel halftrack.

I'd rather share the road with vehicles that have properly operating brakes (and of course, drivers that pay attention to safe driving).
If they still work then it's not taking a short cut, the hydrovac is notorious for being a pain that doesn't work. I removed mine to just have manual brakes, they still work, it still stops, all is well, I just like pushing the pedal harder. Thank you for the lecture on safety though.

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Re: Halftrack vacum booster

Post by Ron D » Mon Apr 18, 2022 2:11 pm

Bradym114 wrote:
Mon Apr 18, 2022 1:37 pm
Thank you for the lecture on safety though.
:D
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Re: Halftrack vacum booster

Post by G102 » Tue Apr 19, 2022 4:13 am

Relying on just a master cylinder is as foolish as it gets on the highway. Yes you may stop your vehicle while you have the time to think about it. When the unexpected moment happens and you need that panic stop , YOU WONT.
the same goes for the hand brake, your brain won’t react fast enough to pull the lever over jumping on the brake pedal.
Last, if you should happen to snap a track while using the parking brake, it’s won’t work. The parking brake is useless with only one track.
Gary

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Re: Halftrack vacum booster

Post by Bradym114 » Tue Apr 19, 2022 4:34 am

.
Last edited by Bradym114 on Tue Apr 19, 2022 8:05 am, edited 1 time in total.

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Re: Halftrack vacum booster

Post by G102 » Tue Apr 19, 2022 5:22 am

It’s foolishness like this that will bring this hobbie down to private property driving only. It seems like a lot of states would like to keep all military vehicles off public roads now. It’s to bad you just can’t fix stupid. I hope you never hurt anyone

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Re: Halftrack vacum booster

Post by jesse » Tue Apr 19, 2022 2:07 pm

Well put Gary.


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