The Stovebolt Site Forums The Shop Area Engine Shop Hydroboost rebuild?

What's it take to rebuild a hydroboost unit? The one on my 61 flatbed is dumbing brake fluid into the vacuum line, so I'm guessing at least on of the seals in there dried up and cracked. It only sat in the dessert for 5-10 years. Also, where can I get the parts? How much is this going to cost me?
Thanks ~ John

Ken mentioned in the lounge that he knows of a place in Seattle that does it in the $200 range.

If you could find a kit for it it's not to tough to assemble/dissassemble one. I took the one on my '49 apart because some sort of bugs climbed in through the vent, nested and plugged things up. I have a shop manual for an International that showed one similar enough to suffice for instruction on taking it apart to clean it out. I didn't change any seals but they all looked good and it was still full of brake fluid. Time will tell if it's going to leak. On mine it appeared ther are only two places where fluid can get into the vacuum line. One is the small plunger behind the diaphragm that switches the vacuum and the other would be the seal on the shaft between the vacuum piston hyd assist plunger.

I've got the 60 shop manual, and that's pretty detailed in hoe to work on it. The only problem I forsee is finding the parts. I really don't want to invest much in it, as this truck is going to be sold as soon as she's drivable. However, I've got to drive it about 500 miles before that, and I think I'll burn all the brake fluid up within about 100. Not a nice thought. I went and talked to the parts stores today, and they all gave this stupid look, and had no clue what I wanted.
~John

Usually have to send them out to rebuilder as mentioned. Brake wholesaler in my area don't even repair or sell parts, just send out. Carter's used to have a kit listed, not sure now, they were having trouble getting when I was looking into it. The shop manual has the repairs in it.
Weird someone else can get parts and fix, why not the rest of us?? The big diaphragm in canister is leather and dries out. You put a little oil in canister to keep it wet. You may be able to by-pass the unit with a line tee and small line or couplings, etc. I ran my 54 for 4yrs with out the booster working and had manual brakes. It was still in system tho. I once had a 76 F-600 U-haul truck with same booster or similar, think it would work on the Chevs, maybe newer truck in yard would still have usable one on it? I've never found a working one on trucks sitting for many years like I usually buy! :rolleyes:

Well, since everything else seems to be okay, I wonder if I can't just replace the seals between the vacuum and brake sides. Are they just o-rings, or something harder to get?
~John

Just caught the tail end of this topic but thought that you all might be interested to know that NAPA auto parts stocks the 'Hydrovac' units for Chevrolet trucks. I just received a reconditioned unit for my 1955 3/4 ton. Ordered it online (www.napaonline.com). Paid about $200. Seems like a good deal to get the unit from a company that provides a limited warranty and has a fairly good reputation.

I think I have seen them in the Jim Carter's catalog, too.

I want to rebuild my 2 ton hydrovac. Can anyone tell me which of these kits is the right one: http://www.piratejack.net/rebuild-kits.html

I forgot a picture of my hydrovac. Sorry!!! Thanks for any advise or help you might be able to provide.

[img]http://members.cox.net/brookebailey/hydrovac1951.jpg[/img]

Hey Virginiafiretruck I think your picture is too big it's messed up the settings on the page.

Oh almost forgot that is gitting too be one sweet fire truck (engine) Truck have ladders Big ladders .

Thanks. I've adjusted the picture's size. How does that work for ya? The sales folk will let me know which rebuild kit I need to buy but I hoped the experiance of this group would insure I get the right parts the first time. Anyone?

The title says Hydroboost.
Y'all are talking about a Hydrovac.
One works of of power steering pump pressure, the other uses engine vacuum.

exactly... And I found it on the Napa web site.

On '60-'66 Chevy trucks, if you are running a single chamber master cylinder forward of your power brake booster, you can remove the booster from the fire wall and install a pedal/plunger from a factory manual brake setup. In essence converting it from power brakes to manual brakes. By doing so, you don't need to break into the system, thus bleeding is not required.

Since you are selling the truck, you may want to keep the factory power brake booster, even if it needs a rebuild. I see them fetching a pretty penny on eBay, from time to time. In fact, I purchase a factory rebuild kit and a complete NOS power brake booster assembly, complete with hardward and factory installation instructions on eBay a short time ago.

I have installed the factory power brake booster on several of my '64-'66 Chevy trucks to complete the power brake conversion. Again, this will only work if you are running a single chamber master cylinder that does not require vacuum or boost for the clutch.