Author Topic: Vacuum booster; is it really needed?  (Read 5307 times)

Smadge

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Vacuum booster; is it really needed?
« on: March 22, 2021, 05:58:20 AM »
Guys,

I need some honest answers for Halftrackers that have EXPERIENCE in running their tracks WITHOUT the vacuum booster.  I never plan on driving down Wolf Creek Pass, and I've heard folks say that the HT has the rolling dynamics of a brick so I need some good first hand experience on the issue. So this doesn't turn into a philosophical debate I have assigned numbers that will explain your first hand EXPERIENCE:

1.  "Stopped with no problem."
2.  "Whoa nellie.........had to pump them a few times but I stopped"
3.  "Had to stand on the brake pedal with my co-driver on my shoulders. I'm re-connecting the booster."
4.  "HELP ME SWEET JESUS".  Sold the track the next day.

Ok dudes, or duderino's (if you're not into that whole brevity thing), please let me know your experience.

Thanks,

Paul
1941 M2-232 Autocar (restoring)
MVPA Member

Monkeypirate

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Re: Vacuum booster; is it really needed?
« Reply #1 on: March 22, 2021, 09:54:08 AM »
Ive tried stopping a 1968 Deuce with a bad hydrovac. Ill say its a good thing the interior can be hosed out. I'm going to guess a Half track at a speed of more then 10MPH is going to be a scary experience. Mass at speed is a scary thing.

mfrance

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Re: Vacuum booster; is it really needed?
« Reply #2 on: March 22, 2021, 10:35:35 AM »
I drive with front and rear brakes running off master cylinder only no hydrovac  I rate it as a #2....  top speed is only realistic  40.     Worse case scenario is grab the e-brake  it will lock up tracks if your in that much of a panic..
Most of us only do parades and small runs in towns...

brit plumber

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Re: Vacuum booster; is it really needed?
« Reply #3 on: March 22, 2021, 02:03:28 PM »
I can’t speak for US regs but in the UK I think (just my opinion) that we would be hung out to dry if after an accident, the vehicle was found to have been factory fitted with a brake aid and it was subsequently removed/disconnected. We have an MOT test for all vehicles over 3 years old, this involves a number of checks to ensure the vehicle is road worthy. Older vehicles are exempt because the Government has decided that a veteran/vintage vehicle owner looks after it much better than say a 15 year old banger. The problem with it is, it puts the onus on the individual to ensure everything is roadworthy. So many owners have their vehicles checked and certified anyway to give them piece of mind.

Off topic, but.....

Some people over here think the USA lead the way in law suits and chasing down ambulances, but I think they should look closer to home. Europe and in particular, the UK are terrible for suing each other for the most trivial of things. Example: The local council put a temporary road sign on my neighbours lawn while they repaired a pot hole (because they could be sued for negligence). They finished and left, leaving the road sign straddling the pavement and their garden. The council sent a warden around to my neighbour to issue a warning about the obstruction his sign had become on the public highway. He pointed out the council ownership markings on the reverse of the sign and pushed it off his land. The council warden made all sorts of comments before leaving with my neighbour shouting to take his F ing sign with him.
1942 VEP GPW

Jesse

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Re: Vacuum booster; is it really needed?
« Reply #4 on: March 22, 2021, 04:19:33 PM »
Pulling the e brake at speed is equally likely to snap the drive shaft as it is to lock up the tracks.

Cleprechaun

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Re: Vacuum booster; is it really needed?
« Reply #5 on: March 23, 2021, 02:38:54 AM »
When I first got my HT running, I wanted to know if the hydrovac did much, so I disconnected it and went for a drive on my dirt road. I just about pulled the steering wheel off trying to stop it. I re attached the vacuum line and it easily made stopping 100% easier. I later found out the hydrovac was nearly shot, so I put a new modern one in. That made it stop 400% better. My advice, get a new master cylinder and a modern hydrovac and adjust any slack out of the slave cylinders and bleed the hell out of the system. Thats what I finally had to do.

Smadge

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Re: Vacuum booster; is it really needed?
« Reply #6 on: March 23, 2021, 06:53:36 AM »
Thanks Guys! Great info!

Paul

1941 M2-232 Autocar (restoring)
MVPA Member

Smadge

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Re: Vacuum booster; is it really needed?
« Reply #7 on: March 23, 2021, 07:19:55 AM »
Ive tried stopping a 1968 Deuce with a bad hydrovac. Ill say its a good thing the interior can be hosed out. I'm going to guess a Half track at a speed of more then 10MPH is going to be a scary experience. Mass at speed is a scary thing.

Ansbach Germany, 1985.  Driving my deuce and a half down a steep hill to a busy intersection. I didn't know the hydrovac was leaking and was picking up a great deal of speed and knew I wouldn't be able to stop.........light changed green for me. I had visions of Angels......scared the crap out of me.
1941 M2-232 Autocar (restoring)
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spec4don

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Re: Vacuum booster; is it really needed?
« Reply #8 on: March 27, 2021, 08:48:56 AM »
My hydrovac went bad so drove it for about a year with out it. Just the master cyl. Even loading and unloading on my step deck. Really never had a problem. The halftrack pretty much slows down on her own. As Mike mentioned the parking brake being a disc brake works extremely well. I lost my brakes coming down the logging road behind the house , the parking brake did the trick!

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

SpencerB

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Re: Vacuum booster; is it really needed?
« Reply #9 on: March 27, 2021, 06:30:00 PM »
I noted a couple of folks talking about "modern" boosters......what are people using?  I believe mine is shot and should be replaced, but am unsure of what would be a compatible model.  Thanks.

Smadge

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Re: Vacuum booster; is it really needed?
« Reply #10 on: March 28, 2021, 05:00:16 AM »
I noted a couple of folks talking about "modern" boosters......what are people using?  I believe mine is shot and should be replaced, but am unsure of what would be a compatible model.  Thanks.
Spencer,
I ordered mine from carquest and I’ll dig up the model a little later. 
Paul
1941 M2-232 Autocar (restoring)
MVPA Member

Smadge

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Re: Vacuum booster; is it really needed?
« Reply #11 on: March 28, 2021, 03:51:18 PM »
1941 M2-232 Autocar (restoring)
MVPA Member