Hydroboost conversion done!
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Joined: Aug 2001
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It can take a bit to bleed all the air out. Which is neat with hydroboost and a clear line retrun line into a bucket. Have a buddy turn the steering wheel and press the brake as you watch the clear line for when the bubbles stop.
As for pedal not returning it's surprising given the internal spring of the hydroboost.
Also, if youa re using a Thompson pump it needs to be in tip-top shape to run both hydroboost and steering. Otherwise it might be time for a Saginaw.
Josh
As for pedal not returning it's surprising given the internal spring of the hydroboost.
Also, if youa re using a Thompson pump it needs to be in tip-top shape to run both hydroboost and steering. Otherwise it might be time for a Saginaw.
Josh
Senior User
Joined: Sep 2005
Posts: 286
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From: Medford, Oregon
I'm interested in the possibility that all of the hydros are made by the same company, any way to verify? Universal rebuild? Easy?
I hooked up the original brake warning light from my Ford to the Dodge hydroboost and master cylinder I used, glad I did as the light came on
. In my haste to get the truck on the road I hadn't fully filled the master cylinder. It's been long enough I might be wrong, but I think the warning switch just grounds to illuminate the warning light. My Dodge sensor/prop valve had a small ground that I hooked up, and only one other wire.Edit, my brake pedal returns slowly, and the pressure reservior(retains boosted operation with dead engine) seems not to be doing it's job, rebuild time me thinks.
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replaced the thompson pump with one that came from same donor as the HB. The pump is the growler. Brake still has same symptoms. I did not know that steering needed to be bled. Are you suggesting that with the wheels off the ground just moving from left to right will not fill the bill?
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Turning the steering wheel and pumping the brakes will bleed out all the air. And if you use a clear discharge line you can see when the bubbles stop.
Just make sure you don't run the pump dry with this procedure.
Josh
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Joined: Dec 2009
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Pedal throw
One thing I've noticed about using the Dodge hydro I did, is the brake lines are on the fender side and the master has a prop valve with a warning sensor. Only downside to a Dodge master is the fittings are metric, no problem as the flares are still the same, just different threads.
Bend dog I read your post on the cummins forum! Great job!!!!!!!!! You are the first that I have seen to notch the frame enough to accept the stock dodge ac compressor. Back on topic I am doing a 78 super cab conversion and am using the 97 dodge hydro boost that came with my donor truck. When I was measuring the stroke of the ford pedal it moves the pushrod 1 1/4 inch, the dodge pedal has 2" of stroke. The ford standoff on my truck multiplied the stroke with the lever to 2". But then the m.c. ran into the air horn. My question is did you mount your hydro boost to the fire wall without the lever apparatus. I am not sure what the effect would be with the shorter stroke? Hope this make sense?
Thanks Hydropower
Bend dog I read your post on the cummins forum! Great job!!!!!!!!! You are the first that I have seen to notch the frame enough to accept the stock dodge ac compressor. Back on topic I am doing a 78 super cab conversion and am using the 97 dodge hydro boost that came with my donor truck. When I was measuring the stroke of the ford pedal it moves the pushrod 1 1/4 inch, the dodge pedal has 2" of stroke. The ford standoff on my truck multiplied the stroke with the lever to 2". But then the m.c. ran into the air horn. My question is did you mount your hydro boost to the fire wall without the lever apparatus. I am not sure what the effect would be with the shorter stroke? Hope this make sense?
Thanks Hydropower
Cargo Master
Joined: Oct 2010
Posts: 2,674
Likes: 16
From: Ideeho
I never coud find what year of SD hydroboost you used. Didnt they start building the SD's in the late 80's or early 90's??? And they still build them so that gives you a pretty wide range. Any help would be appreciated.
So I got really tired of the braking system on my 76 F-250 SuperCab 2WD
. I had replaced everything multiple times and it still was not that good. So I decided to do a HydroBoost conversion. Some people put way to much thinking effort into this conversion but its really is not that hard. I decided to just jump into it and get it done!All the parts I used can be found at a local parts store or junkyard I got mine from a junkyard.
Parts list
F-450 HydroBoost found on the F-SuperDuty trucks $24.00
HyrdroBoost mounting bracket from F-450 $2.00
Both pressure lines from the F-450! $19.00
Master Cylinder "NEW at NAPA" for 79 F-350 SuperCab $31.00
Power Steering Pump from the F-450 $ 20.00
Bulk High pressure 3/8'' oil cooler hose 6' $28.00
That will give you the main parts you need to get. Other parts such as clamps and oil are common sense. The install went very well and almost ZERO fab work. First remove the pushrod from the brake pedal inside the truck.Make sure you keep the stock bolt, bushing and nut you will be reusing these. Now go and remove the master cylinder and set it aside. Start unbolting the vacuum booster, start by removing the 4 nuts on the rear of the unit that hold it on to the brackets. Now remove the two brackets that held the booster to the firewall and keep the bolts you will reuse them. Go ahead and remove the black plastic dust cover that mounted between the booster and the firewall and discard. You now have a fresh start all the parts are off the truck and you are ready to mock up the HydroBoost.First start by removing the 4 studs in the HydroBoost bracket and discard them. The F-450 mounting bracket has to be removed from the HydroBoost and flipped 180 degrees to do this remove it and you will see a small tang. Just make sure you do not flip the bracket the flush side without the edges goes towards the firewall. Notice how the factory just cut a groove in the threads on the rear of the HydroBoost for the tang to fit. Go ahead and cut a new slot on the other side and make sure it is straight if not your booster will sit crooked. Now go ahead and put the mount back on the rear of the HydroBoost and tighten the nut and put the snap ring on. Take two of the stock bolts that went to the firewall and put them in the top 2 holes of the HydroBoost now bolt the hydro boost to the firewall. You will notice the bottom two holes need to be slotted upwards, mark them with a pen and remove the booster. Use a die grinder and create the slots in the bracket. Once done put all 4 bolts in and tighten down. Go inside and hookup the pushrod to the pedal. The pushrod has two sides to it one is flat the other has a bump you want the flat side towards the pedal. Reuse the stock bolt bushing and nut and tighten. Go and start running the pressure lines, the stock HydroBoost line will thread into your stock steering gear so no problems there. You will have to get creative and do some gentle
bending of the tubes to adapt them to fit in these trucks. But they will fit. So one line goes from the pump to the left hand port on the HydroBoost then the right hand port goes to the steering gear. Depending on if you got the power steering pump with two return lines will determine how you will have to run the return lines. Run one return line from the stock PS cooler output to the pump then run the HydroBoost return line to the other return port on the pump (if you don't have 2 return ports on the pump just tee all 3 lines together). You're almost done go ahead and fill the PS reservoir (you may have to do it a few times after initial start once the are bubbles work their way out) bleed all the brakes. Go ahead and start the truck and check for leaks and test out your new braking power!
. I had replaced everything multiple times and it still was not that good. So I decided to do a HydroBoost conversion. Some people put way to much thinking effort into this conversion but its really is not that hard. I decided to just jump into it and get it done!All the parts I used can be found at a local parts store or junkyard I got mine from a junkyard.Parts list
F-450 HydroBoost found on the F-SuperDuty trucks $24.00
HyrdroBoost mounting bracket from F-450 $2.00
Both pressure lines from the F-450! $19.00
Master Cylinder "NEW at NAPA" for 79 F-350 SuperCab $31.00
Power Steering Pump from the F-450 $ 20.00
Bulk High pressure 3/8'' oil cooler hose 6' $28.00
That will give you the main parts you need to get. Other parts such as clamps and oil are common sense. The install went very well and almost ZERO fab work. First remove the pushrod from the brake pedal inside the truck.Make sure you keep the stock bolt, bushing and nut you will be reusing these. Now go and remove the master cylinder and set it aside. Start unbolting the vacuum booster, start by removing the 4 nuts on the rear of the unit that hold it on to the brackets. Now remove the two brackets that held the booster to the firewall and keep the bolts you will reuse them. Go ahead and remove the black plastic dust cover that mounted between the booster and the firewall and discard. You now have a fresh start all the parts are off the truck and you are ready to mock up the HydroBoost.First start by removing the 4 studs in the HydroBoost bracket and discard them. The F-450 mounting bracket has to be removed from the HydroBoost and flipped 180 degrees to do this remove it and you will see a small tang. Just make sure you do not flip the bracket the flush side without the edges goes towards the firewall. Notice how the factory just cut a groove in the threads on the rear of the HydroBoost for the tang to fit. Go ahead and cut a new slot on the other side and make sure it is straight if not your booster will sit crooked. Now go ahead and put the mount back on the rear of the HydroBoost and tighten the nut and put the snap ring on. Take two of the stock bolts that went to the firewall and put them in the top 2 holes of the HydroBoost now bolt the hydro boost to the firewall. You will notice the bottom two holes need to be slotted upwards, mark them with a pen and remove the booster. Use a die grinder and create the slots in the bracket. Once done put all 4 bolts in and tighten down. Go inside and hookup the pushrod to the pedal. The pushrod has two sides to it one is flat the other has a bump you want the flat side towards the pedal. Reuse the stock bolt bushing and nut and tighten. Go and start running the pressure lines, the stock HydroBoost line will thread into your stock steering gear so no problems there. You will have to get creative and do some gentle
bending of the tubes to adapt them to fit in these trucks. But they will fit. So one line goes from the pump to the left hand port on the HydroBoost then the right hand port goes to the steering gear. Depending on if you got the power steering pump with two return lines will determine how you will have to run the return lines. Run one return line from the stock PS cooler output to the pump then run the HydroBoost return line to the other return port on the pump (if you don't have 2 return ports on the pump just tee all 3 lines together). You're almost done go ahead and fill the PS reservoir (you may have to do it a few times after initial start once the are bubbles work their way out) bleed all the brakes. Go ahead and start the truck and check for leaks and test out your new braking power!
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Joined: Nov 2011
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Hey First Post, I was searching the internet for info on a hydro conversion for my 77. My booster went bad and I already ordered the 78 F350 dual diaphram MC combo but I would really like to ditch my vacum pump(diesel conv) and go hydro. My 77 has a bracket from the pedal to the booster, the booster does not directly attach itself to the pedal. I am trying to figure out which version, early or late SD, since the rod is shorter or longer. This does seem to be the most comprehensive thread on a hydro conv to a dent but this pertinent info I did not see.
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Joined: Nov 1999
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From: 15 miles west of Venus
https://www.ford-trucks.com/user_gal...170466&width=0
This allows you to bolt to the firewall using existing holes and keep it close for max clearance.
This allows you to bolt to the firewall using existing holes and keep it close for max clearance.
Cargo Master
Joined: May 2009
Posts: 2,587
Likes: 47
From: Eagle River, AK
ford390gashog - Thanks for the great write-up and thread. I just found a guy up here that is thinking about parting out his 94 F-450 Super Duty. If he does and does not want an arm and a leg for the stuff, I will have it soon. If not, I will then just start buying new pieces, one piece at a time.
Between this and a Red-Head steering gearbox (hopefully next year), this baby should be steering and stopping real good.
Between this and a Red-Head steering gearbox (hopefully next year), this baby should be steering and stopping real good.
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Joined: Nov 2011
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Dont get screwed like me
No where I researched did I come across the fact the the new HD units do not come with the rod-spring-spring holder! Although my HD unit was for a f450 I had to find those items in the junkyard off a astro van, there fore I was forced to use a astro MC and had to do major line changes and stuff.
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No where I researched did I come across the fact the the new HD units do not come with the rod-spring-spring holder! Although my HD unit was for a f450 I had to find those items in the junkyard off a astro van, there fore I was forced to use a astro MC and had to do major line changes and stuff.
Josh
