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BrianC
07-17-2012, 07:34 PM
After the hydro-vac booster failed on my 63 GT Hawk and caused an accident, i am replacing it with a modern conversion from Summit racing. According to the tech there, i don't need a pedal conversion? I cant see how to this possible? Has anyone done this conversion, the brake pedal on the Hawk goes under the floor to the existing master cylinder. What exactly is required to complete the pedal hook-up.
Thanks.

SN-60
07-17-2012, 07:57 PM
To: BrianC,--------That's too bad Your brake booster failed, Your definitely not the first person that's happened to though. Could You please describe what this Summit conversion entails?

BrianC
07-17-2012, 08:10 PM
This is a 7" power brake booster, dual circuit master cylinder and proportioning valve. It's for front disc/rear drum. It will replace the existing Hydro-vac and master cylinder. It is essentially a modern chevy power brake system. Mounts on the firewall with the linkage to the pedal under the dash. The required linkage configuration is my question, i'm sure there are Hawks out there with this set-up.

Dan White
07-17-2012, 08:18 PM
Brian:

I doubt the technician at Summit has a clue as to what a Studebaker brake system on a Hawk is like and that there are different length brake pedals and the master cylinder is under the floor Is this unit to replace an under the floor unit or convert to a firewall setup? If it is for a firewall application you will need to install swinging pedals. Does the kit also include disk brakes? We need more details to give you some pointers. Summit sells lots of brake conversion kits but I am not aware of any that will work on a Hawk without a boat load of reengineering.

How exactly did your Hydrovac fail? I have had them go bad and it results in basically manual, i.e. no power brakes but never a loss of all brakes. The only place that would be apparent are the rubber hoses going from the unit to the brake lines.

Dan White
07-17-2012, 08:21 PM
Brian:

I responded while your second post was in progress. There are Hawks with firewall units but none are factory. All Hawks came with under the floor master cylinders. Someone that has rodded their Hawk would be best to answer this.

sweetolbob
07-17-2012, 09:26 PM
Brian:

I responded while your second post was in progress. There are Hawks with firewall units but none are factory. All Hawks came with under the floor master cylinders. Someone that has rodded their Hawk would be best to answer this.

Brian

I put a 1989 Camaro IROC pedal setup on my 54K. Several thoughts: First, the firewall is not stiff enough IMHO to provide adequate support for the M/C so it needs to be stiffened, which I did. Secondly, I used all IROC brake components so it matched up well. But in your case, you will need to be sure that M/C you have has the same capacity as the original Stude unit in the 63.

If you don't have the pedal assembly, you could probably get that from Summit or a wrecking yard from a car that Summit recommends but, I think you are going down a difficult road that has several draw backs.

Let me suggest before you go through all of this you contact Jim Turner, Turner Brake - 52ragtop on the forum, and talk to him about what you are trying to do. He knows Studes well, knows brakes and sells stuff that works. He should make your life easier.

Summit is great at taking stuff back.

JMHO, Bob

Dick Steinkamp
07-17-2012, 09:32 PM
Brian,
I'd get back on the phone with Summit. Tell them what you were sold, and ask them how it should be installed.

Captain Billy
07-18-2012, 05:40 AM
Brian....you could try this set up http://www.speedwaymotors.com/Under-Floor-Power-Brake-Hydraulic-Clutch-Assembly,46286.html

would require mounting mods but is doable

Dan White
07-18-2012, 06:39 AM
Depending on your engineering talent and wallet you may want to rethink your approach. As Bob noted above I would suggest you contact Jim Turner and discuss converting to modern front disk brakes, and you can also go with a dual master cylinder under the floor. Also going back to my previous post, are you sure your original master cylinder is not at fault for the accident? If the bore is shot/corroded or the piston rubber is bad you can have total brake failure, which has nothing to do with the hydrovac.

BrianC
07-18-2012, 08:00 AM
I was getting brake fluid backing up in the intake manifold, smoking quite badly. No pedal, the Hydro-vac would squeal when the brake was applied. All hoses and lines are good. After many suggestions from Stude forums, rebuilding it is not cost effective.
This unit is to mount on the fire-wall. Summit assured me that they are familiar with the Hawk, but now that the unit has arrived, i'm not so sure???? i only recently learned of Jim Turner, but have no contact info. If i have to return this to Summit and go to Jim Turner, then so be it. I 'm frustrated enough, finding body parts, dealing with body shop and no Hawk for the summer!

BrianC
07-18-2012, 08:04 AM
Theres no way that the unit suggested by Captian Billy will give me enough ground clearance.

BobPalma
07-18-2012, 08:08 AM
Brian: Does your Hawk have drum or disc brakes in front?

If they are drum, Studebaker International now sells an all-new (NOT rebuilt) Hydrovac units for that application, for only $360.

That is an option for consideration that wasn't available even a couple years ago. BP

jd-stude
07-18-2012, 08:18 AM
A new or rebuilt hydrovac is in the $400 price range last time I looked and about 1 hour of simple wrench word to install. Modified stystems might have half the dollar cost but the installation/engineering to get it to work has a price too. I'd bite the bullet and spend the money and be driving the car at the end of the week and know it will work. The hydrovac may seem to be a troublesome unit but they are 40 plus years old in many cases and are due for replacement or service. My project Hawk needs one but I bypassed it until it is road ready and it will get a new one when the time comes.

Ken

studebaker-R2-4-me
07-18-2012, 08:41 AM
Brian:

How exactly did your Hydrovac fail? I have had them go bad and it results in basically manual, i.e. no power brakes but never a loss of all brakes. The only place that would be apparent are the rubber hoses going from the unit to the brake lines.

I lost all brake's on my 64 Hawk right in the parking lot during last years spring swap meet in South Bend. The brake pedal went right to the floor. Had brakes one minute and absolutely no pedal the next. What happens is the diaphragm fails and brake fluid is sucked up into the vacuum hose and then into the engine leaving NO brake fluid. Number one reason NOT to use silicon fluid in a hydrovac car!

I replaced my disc brake hydrovac in the 4H fairgrounds with a new production hydrovac from SI. Easy fix and is working well.

I would suggest that Brian rethink his conversion and install the brand new Hydrovac from SI and be done with it.

Allen

BrianC
07-18-2012, 09:35 AM
Thanks for the input, very leery about a new hydro-vac, but it does seem to be the simplest solution. Hawk has front disc. I've heard from a couple of Stud owners that the that that they have had not such good luck with new Hydro-vacs, only lasting a couple of years???? So you see my reasoning for a modern unit? How are Summit with refunds???

studebaker-R2-4-me
07-18-2012, 09:53 AM
Thanks for the input, very leery about a new hydro-vac, but it does seem to be the simplest solution. Hawk has front disc. I've heard from a couple of Stud owners that the that that they have had not such good luck with new Hydro-vacs, only lasting a couple of years???? So you see my reasoning for a modern unit? How are Summit with refunds???

Brian, I have no idea with Summit refunds but I think they are unaware of the geometry of the brake pedal, and that the master cylinder is attached to the frame rail under the car. If they sold you this system for a firewall mounted booster it was most likely for a Lark which has a totally different setup from a Hawk. That alone should be enough for a full refund. You really don't want to re-engineer the braking system.

I've had NO luck with rebuilt hydrovac units. The pressed ring seals in the hydrovac and the banjo brake fittings are highly worn in rebuilt units and don't seal that well (my experience). I have had my present (new manufactured) hydrovac for two seasons and have had no problem thus far. I would bet that your hydrovac did not have the check valve in the vacuum system and was removed during it's life. All it takes is one backfire and it could blow the seal in the hydrovac and cause failure. The new manufactured unit have a check valve built into it. Of all the re-manufactured units that I installed in my Hawk did not have a check valve! The original check valve was factory installed in-line with the vacuum hose to the intake manifold. They are NLA and have been for years.

Best of luck.

Allen

sweetolbob
07-18-2012, 10:00 AM
So you see my reasoning for a modern unit? How are Summit with refunds???

Excellent, just call them for a return authorization, tell them it won't fit and they may even pay for the return. One of the reasons I check them first for parts.

Bob

BrianC
07-18-2012, 12:12 PM
Ok ,thanks so much, Now how do i contact Jim Turner? I'd like to talk to him rather than endless e-mails. Thanks.

Mike Van Veghten
07-18-2012, 12:15 PM
Brian -

Do some homework and don't even use a booster...!

I have disc brakes on all four corners of my 54 wagon...with "no" booster of any kind. It stops great with just medium pressure. A normal stop can be done with the toes only...!

I'm getting ready to make a different 54 wagon my daily driver. 4 wheel disc, no booster, stock pedal length.

All the hassle you are going thru.....not required. Just pick the master cylinder piston size that "properly" matches the piston area of the 2 (4) calipers. You need about 1200psi line pressure. While your pedal may need altering to easilly atain the pressure...."either" end of the pedal arm can be modified if you need.
Easy........

Mike

sweetolbob
07-18-2012, 12:57 PM
Ok ,thanks so much, Now how do i contact Jim Turner? I'd like to talk to him rather than endless e-mails. Thanks.

Here's his website with all contact info including Phone # http://www.turnerbrake.com/

Bob

Dan White
07-18-2012, 01:34 PM
Studebaker Intl also has the Disk/drum hyrovacs new for $375 (part #802101). Not a bad price for a new one! This is really a bolt in, bleed the brakes and go.

BrianC
07-18-2012, 05:57 PM
Thanks, i've sent an e-mail to Jim Turner and look forward to hearing from them.

Kdancy
07-19-2012, 05:59 AM
Brian -

Do some homework and don't even use a booster...!

I have disc brakes on all four corners of my 54 wagon...with "no" booster of any kind. It stops great with just medium pressure. A normal stop can be done with the toes only...!

I'm getting ready to make a different 54 wagon my daily driver. 4 wheel disc, no booster, stock pedal length.

All the hassle you are going thru.....not required. Just pick the master cylinder piston size that "properly" matches the piston area of the 2 (4) calipers. You need about 1200psi line pressure. While your pedal may need altering to easilly atain the pressure...."either" end of the pedal arm can be modified if you need.
Easy........

Mike

Mike, what all did you use to build your brake system? What size lines and MC ? Where did you mount the MC?

bezhawk
07-19-2012, 07:16 AM
I cut down a Wagonaire suspended pedal assy and installed it in my 53 Commander HT many years ago. It ties into the dash cross brace and was very stout. Didn't use any booster, and it stopped very well.

G T Joe
07-19-2012, 09:13 AM
This is only a theory of mine, I noticed more failures with hydrovac's over the years that were rebuilt , I think the reason is we have changed the formula of the brake fluid, your large heavy duty trucks have used hydrovacs for many years , when I worked on fleet where we had a lot of older trucks that used hydrovacs when the new dot 3 & 4 came out it seemed that when we did a brake job and replaced some lines or wheel clyinders and then soon after a month or more the hydrovacs would fail, I had a 56 packard that had a BRAND NEW hydrovbac not rebuilt and it prematurely failed, in less than a year , just some food for thought.

BrianC
07-19-2012, 10:05 AM
Well thanks to all for your input. Summit Racing have agreed to take refund the unit from them and Jim Turner is supplying me with the proper unit for the Hawk. Easy no fuss install from what he tells me.
Brian

sweetolbob
07-19-2012, 10:53 AM
Well thanks to all for your input. Summit Racing have agreed to take refund the unit from them and Jim Turner is supplying me with the proper unit for the Hawk. Easy no fuss install from what he tells me.
Brian

Don't you love it when a plan comes together.:)

The forum has a wealth of resources, Just gotta figure out how to use 'em sometimes.:!:

Bob

bezhawk
07-19-2012, 06:37 PM
This is only a theory of mine, I noticed more failures with hydrovac's over the years that were rebuilt , I think the reason is we have changed the formula of the brake fluid, your large heavy duty trucks have used hydrovacs for many years , when I worked on fleet where we had a lot of older trucks that used hydrovacs when the new dot 3 & 4 came out it seemed that when we did a brake job and replaced some lines or wheel clyinders and then soon after a month or more the hydrovacs would fail, I had a 56 packard that had a BRAND NEW hydrovbac not rebuilt and it prematurely failed, in less than a year , just some food for thought.
Packard used the "TreadleVac" NOT the HydroVac. totally different beast.

BrianC
08-06-2012, 08:19 PM
Yes, GT Joe, i've heard of one too many new units fail after a year or two. I can't take a chance on another brake failure! If somewhere down the road, a future owner wants it to be all original equip., it's do-able,and good luck with it.
Though i'm losing power assist to the disks, i'm confident with the JT unit will provide more than enough braking power- with a strong foot...ha.

Dan White
08-07-2012, 06:17 AM
I had my Hydrovac rebuilt about 15 years ago and it has not had any problems since and stops on a dime. If you service them per the manual you should not have any issues. I think most of the issues have to do with not having them rebuilt by someone that knows what they are doing, and also not following up servicing it with Neat's foot oil. Hydrovacs were used by many manufacturers over the years including Mercedes Benz, GM, Ford, and are still being used in some applications still today. One of the guys in the Hudson club actually retrofitted one on a Hornet with good results.

jimmijim8
08-08-2012, 07:16 AM
Had my drum brake booster remanufactured by {Rebuilders Enterprises} located in Illinois. They use a modern material diaphram that does not require a yearly infusion of neatsfoot oil. 200 plus shipping. 3 yr guarantee. As stated previously, the banjo fittings are sometimes hard to seal so I used a small amount of copper type head gaskett sealant on both sides of the copper washer. cheers jimmijim

BrianC
08-14-2012, 11:50 AM
I'm about to make an attempt installing the master cylinder (under the floor) that i received from JimTurner. However the instructions are hopeless,as clear as mud, no diagrams. I'm supposed to be able to lock the proportioning valve, once adjusted ,with the set screw, the screw doesn't exist???? No way to lock it? Install RCV Residual check valves, no indication of what direction ? There is no way i can tell what is "in" and what is "out" for the lines.
I'd appreciate any input from anyone who has installed this unit. Thanks.

Dan White
08-14-2012, 01:42 PM
I would contact Jim Turner since he is the one the designed and built it.

BrianC
08-21-2012, 07:39 PM
I installed a master cylinder, but couldn't get any fluid to the calibers! The in-line residual check valve has an "in" end. Does this "in" mean " fluid in" from the master cylinder or in to the calibers? That's how i had it installed and there was no fluid coming through. I switched it around and got fluid and air to the rear caiber. Now i don't know what "IN" means and i'm not sure by switching it if i destroyed it? Instruction sheets are lacking just a simple diagram, what would it cost!!!!

BrianC
01-06-2015, 04:42 PM
Thanks to everyone for all your input. After a summer of driving without40368 power assist to the disc, i decided to search out a kit to repair it myself. I had no luck finding a kit, however Ed Strain in Fla. will rebuild it for a very reasonable cost. Unfortunately it will cost that much again shipping back and forth from here in Canada.

dallastx75208
01-06-2015, 09:20 PM
Had mine rebuilt about 8 years ago by a trucking company in St Louis and it is still working great. Glad I added it to my 62 Hawk. Feel much better about stopping.

Thanks to everyone for all your input. After a summer of driving without40368 power assist to the disc, i decided to search out a kit to repair it myself. I had no luck finding a kit, however Ed Strain in Fla. will rebuild it for a very reasonable cost. Unfortunately it will cost that much again shipping back and forth from here in Canada.