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Illustrated Hydroboost swap

Hey does anybody have any pics of the hb setup with the abs module?
Need some reference material
I have seen it before in person but cannot remember where the proportion valve mounts
 
I have rear antilock...I'll look tomorrow.
 
Factory Hydroboost setup in my 88 Crew Cab V30. Lifted the truck this weekend and changed the box out to the 2WD unit for a cross over steering set up. Got everything together, ran the truck, no bubbles or anything, steered fine in the garage and the truck and had good brakes.

Took it out for a shake down run around the section and I lost both power steering & power brakes. I took it back in and went through the bleeding procedure that was posted earlier in this thread and still nothing... I did get some bubbles out while doing this but I still don't have any power brakes/steering.

It's entirely possible I smoked the pump somehow but it was working fine up until about 5-10 minutes into the drive... any thoughts??? Could I have just some massive air bubble that needs worked out still???
 
If it was just some air, I would expect some steering assist, even if it was noisy. I would pull off fittings and look for some debris stuck in there. After that, pull the valve out of the back of the pump to inspect/clean. For troubleshooting you could also go backwards and bypass the hydroboost unit.
 
Thanks... that was my other thought was debris in the line somewhere... I'll just have to tear it apart and start the process... Thanks for the help
 
Factory Hydroboost setup in my 88 Crew Cab V30. Lifted the truck this weekend and changed the box out to the 2WD unit for a cross over steering set up. Got everything together, ran the truck, no bubbles or anything, steered fine in the garage and the truck and had good brakes.

Took it out for a shake down run around the section and I lost both power steering & power brakes. I took it back in and went through the bleeding procedure that was posted earlier in this thread and still nothing... I did get some bubbles out while doing this but I still don't have any power brakes/steering.

It's entirely possible I smoked the pump somehow but it was working fine up until about 5-10 minutes into the drive... any thoughts??? Could I have just some massive air bubble that needs worked out still???

You can smoke a pump really fast. I ruined mine while bleeding air after installing my new ram assist. If the fluid gets low even for a minute it will be done. I'm suprised how fast it happens.
I hope that's not the case though.
 
always front wheels off ground .

engine off.

cycle wheel left/right 1-2 times .

refill and repeat as needed till no more change .

then press brakes full up to 10 times till no more assist left .

fire off engine 5-10 sec and shut off and refill as needed and re fire and check / cycle / fill as needed . also depress brakes and check fluid level .

do this till all air is out . and level don't change .

shut engine off and press brakes again 5-10 times till no more assist . hold brakes to floor and fire up . pedal should drop a bit and then pressback firm and hard to verify boost is working .


it can be a slow and pita job but the best way to do it . seen way to many shop guys install fill 1 time fire up and refill as needed and have major foam oil mix and growling for ever . warning tags on new / reman pumps not say if done this way warrenty void.
 
Great thread, I need to print this up and put it in my book.
 
Agreed, good thread. I just have one (probably dumb) question that I don't think was asked before. On a square body hydro boost system, what is the recommended fluid to run? DOT3? DOT5? I assume it's the same for both master cylinder and p/s pump since they share fluid through the return lines, but what's recommended? Thanks all!
 
DOT 3 in the master cylinder,power steering fluid or Dextron ATF in the P/S pump...they do not "share" the same fluids...the hydroboost and P/S shares the same fluid,but brakes never use anything but brake fluid..
 
Exactly. So you will use the same fluids after the swap that you used before the swap.
 
Before i packed it away i was going thru my 90 RV parts bible and it showed the same pedal assembly for both vacuum and hydro boost.
Going to assume that's an RV series deal. Do to life being a pita my swap is on hold. I think us poor sods with the ABS systems will have to do what Larry did and relocate the prop valve to its non abs valve location on the front cross member.
 
Yup, even with all the great info in this thread I have run into many glitches converting to hydroboost. First off my 85 donor truck must have been converted before I got it. It had flair style fittings in stead of the O ring style I required. So, I ordered (in kind) like recommended thinking I would soon have new parts to simply bolt on. WRONG! The booster I ordered for a 1990 K3500 did not come with the mounting plate. No problem, I will use the one off the old booster. Except someone had welded it on. Be aware that your going to need a special square socket for the big nut that holds the booster to the firewall plate. Also my new master booster combo did not come with the pushrod that is the link between the two. No problem! I will just use the old pushrod from the donor truck. WRONG! Different lenth, not compatable. OK, sending 1990 master back & ordereing a 80s style that is compatable with current pushrod, troubles over. WRONG! Upon installing booster I find that the pushrod between the pedal & the booster is also a different lenth. It looks as if the ball on these things is crimped in. I was not sure how to remove the pushrod so I just took a rod threw the loop & popped it out with a whack of the hammer. Seems to have worked fine. To install I just whacked again but now my pedal does not return completely. I am hoping it will when the system has been run under pressure.

image.jpg
 
My advice is much like others. When converting make sure to get everything from donor vehicle. Pedal assembly, booster, master. Then document what year the stuff came out of. That way when replacing components down the line you know what to order. Also stay away from the pre 80's systems. When you go to a hydro assist steering system you will want o ring style fittings everywhere.
 
It looks as if the ball on these things is crimped in. I was not sure how to remove the pushrod so I just took a rod threw the loop & popped it out with a whack of the hammer. Seems to have worked fine. To install I just whacked again but now my pedal does not return completely. I am hoping it will when the system has been run under pressure.

Interesting. I cracked that ball socket a few days ago. The rod now falls out when the pedal is returned. :doah: :doah:

20161024_215213-jpg.218017


20161024_215220-jpg.218019



So I personally would avoid whacking it unless absolutely necessary. It's fragiler than I realized, I'm still not sure what I did to cause it to split like that. Are you saying that you replaced the socket? Or just the rod? I'm in need of ideas here... :thinking:



FYI, the pedal isn't supposed to come all the way back up when attached to the booster. At least, none of my 3 pedals do.
 
I had to replace the pushrod with one of the correct lenth for my application. I would have chose not to. Here is a picture of my " whacking" procedure & the crimp. This is actually a different crimp but the one I changed yesterday is installed

image.jpg

image.jpg
 
The other older booster looked like it had a rubber socket that the ball fit into.
 

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