2nd series Hydrovac

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2nd series Hydrovac

Postby plainjanedoe » Tue Jan 06, 2009 12:03 pm

Does anyone know of a place that rebuilds them? Or has a rebuilt one for sale? Or the Kits to rebuild them? Tryin to get the old Girl up and running for the Febuary Rally. Have all other parts... it's the last Hurdle.
SD
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Re: 2nd series Hydrovac

Postby pfarber » Sun Jan 11, 2009 1:25 pm

Yes, they can be rebuilt. Yes I have a kit to do it (NOS Bendix), and yes the kits are available. Rebuild takes about 2-3 hours and is pretty straightforward. There are only a few critical parts that need measures (a dial Caliper is the best tool).

If you do not have the TM9-1827A Vacuum Brake Systems (Bendix B-K) or civvy service (I have to finish the manual for posting on this site) manual then rebuild is still possible (my first attempt was with nothing more than the SNL and the parts kit.

There is only one major part than can stop a rebuild and that is of the Power Cylinder (the big metal tube) has corroded and is no longer smooth. The leather seals will simply get torn up if they have to operate with a rough surface.

How much is a parts kit? Several hundred dollars (SEVERAL). One can rebuild them on the cheap if you can find T-17 rebuild kits (they used the same vac only with one piston... so you would need two to replace all the piston seals.

Vehicles of Victory has replacement '4th Series' vac for $300 (includes a new mounting bracket).

What year is your truck? You may be able to use the 3rd series Vac (much cheaper to rebuild) and still be 'original'.

I will add the TM9-1827A to the Technical Publications page tonight.
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Re: 2nd series Hydrovac

Postby plainjanedoe » Tue Jan 27, 2009 4:49 pm

Hey thanks!
We have a 1942 short wheelbase cckw.
We found a place to rebuild it, we simply don't want to mess w/ it our selves, and they cant find the kit.
You say you have the t-17 kits NOS? How much and are they good?
I can get a 3rd series 374750 which is the replacement hydrovac. (?) but we would need the "mod" mounting kit. Do you have or know where I could get one of these?

I have an email out to Muller @ V of V, we actually bought most of the other parts from him all ready.

Thanks for your Help!!
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Re: 2nd series Hydrovac

Postby deadline » Fri Feb 06, 2009 8:29 am

Rebuilding a vac is pretty simple. Since the hydrovac is still in common use today there are lots of places that can rebuild them.... but as you found out the parts are the biggie.

If you just want the control valve rebuilt, you can use the T-17 kit. If you want to do the whole thing you'll need two as the T-17s only used single piston series II vacs.

Where to get them.. the $64 question. VoV is where I got my T-17 rebuild kit. Look overseas. The Staghoung was not really a US vehicle (most went to the UK). VoV has the brackets for like $80... unless you are going for a 100% resto the VoV Vac is close enough to the 3rd series that no one will know. If you have access to a press I'm sure you could make something work as its just a 90deg bend with some holes. DUKWs also used the 2nd series vac.. and there are a lot of DUKW places around.
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