Hydroboost conversion, got a problem

[Nasty]

Did the conversion today, ran into some snags with the install but worked through them and got everything hooked up. After bleeding the ps and brake systems, I have a huge problem.

The brake pedal does not come back up after applying the brakes and the brakes stay applied. If you lift up on the brake pedal the brakes release. Of course you can hear the pump load up when they are stuck on. I did have some issues with getting the air out of the ps system, the fluid, booster, lines got very hot. Not sure if the pedal was stuck on at the time, it may have been and that may have been the cause of them getting hot. The brakes do feel awsome during that first apply, gets about halfway down and wow you come to a hard stop!. Just the pedal does not come back up by itself unless you lift up on the pedal. Feels like maybe something is hung up. Bad booster?

Looking for advice and direction.

 

[novaderrik]

i think some people have problems on the return side of things- the fluid can get into the booster, but it can't get back out to the reservoir after the pedal is released.

 

[1quick6]

Is the T for the return line pointing up towards the booster? I mean, there's hardly a way to do that wrong, but there does need to be a nice path from the booster to the T. Just making sure.

 

[Nasty]

Is the T for the return line pointing up towards the booster? I mean, there's hardly a way to do that wrong, but there does need to be a nice path from the booster to the T. Just making sure.

To describe how I have the t oriented, imagine standing in front of car, looking at the ps resevoir. I placed the t so middle nipple goes to the resevoir, one end points slightly up towards the booster (at an angle, say 2:00?) and that makes the other end point toward the engine making its angle about 8:00.

Think this has any bearing?

 

[1quick6]

On an IC car, the T would be going parallel to the front of the car with the middle nipple going up to the return on the booster. It would be angled up at about 2 o'clock or so. The middle nipple does have to go to the return port on the booster.

 

[Nasty]

On an IC car, the T would be going parallel to the front of the car with the middle nipple going up to the return on the booster. It would be angled up at about 2 o'clock or so. The middle nipple does have to go to the return port on the booster.

Ok, so the nipple should be like this...
Gear return straight thru to the return, the middle nipple angled up slightly in the direction of the booster.

I have it so its straight thru from the booster to the gear, and the middle nipple to the return. My thought was the return from the booster and the return from the gear meet and then go into the resevoir. I guess the way I have it now, maybe the return fluid from the gear is overpowering the return from the booster? Not sure if that is possible but its the only reason I can think of that would make the orientation of the t a factor.

Can you elaborate on why the orientation of the t is important? I dont remember reading anything that emphasized it? I will take a ride over to work tomorrow morning and install it the other way and see how it goes. Sure would be great if that is all thats wrong.

 

[1quick6]

Your thought is correct. From my understanding, the higher pressure from the steering box is pushing the lower pressure coming from the return on the booster. This will restrict flow and apply your brakes full time until you pull that pedal back up. The pedal can only return to the correct position as fast as the fluid is able to return. Change it so that your middle port on the T goes to the booster and report back.

The other possibilities are air in the system or a bad booster, but I think it is the T orientation.

 

[turbonut85]

The piston on the booster is hanging up on the snap ring in the master cylinder. Happened to me. Sometimes the reman masters come with the wrong snap ring in them. The correct one is just a "C" snap ring. The INCORRECT one has the "ears" that protrude into the bore, and hang up on the booster piston....thus, not allowing the pedal to return. Here are a couple of pics explaining what I'm talking about.....
Pic 1: CORRECT.



Pic 2: INCORRECT

 

[Nasty]

Ok, will try the t first, easy solution. It does feel like it is hanging so that c clip may be the answer too. Unbolting the mc may not be a big deal to check if the t does not resolve it.

Can I change the clip myself if needed? Or do I have to get another mc?

 

[1quick6]

Let's hope the T does it, but Keith has done enough of these to have experienced everything that can go wrong. I want to know if he was out in the shop taking pictures at midnight or if these were in his archive.

 

[Nasty]

T did not fix it, sadly. Worse yet the master cylinder has the CORRECT snap ring. With the master cylinder off, I can feel the spot that is hanging up when moving the brake pedal up and down. I am convinced there must be an issue within the booster. That is the reason I hate ordering stuff, over the internet, if there is an issue you cannot just go to the store to make the exchange . Sure hope RockAuto is easy to deal with.

Any other ideas before Tue are welcome, otherwise looks like a phone call for a RMA or however they handle it.

 

[turbonut85]

Let's hope the T does it, but Keith has done enough of these to have experienced everything that can go wrong. I want to know if he was out in the shop taking pictures at midnight or if these were in his archive.

A little from column A......a little from column B......



Guess the booster is the culprit.....:frown:

 

[1quick6]

T did not fix it, sadly. Worse yet the master cylinder has the CORRECT snap ring. With the master cylinder off, I can feel the spot that is hanging up when moving the brake pedal up and down. I am convinced there must be an issue within the booster. That is the reason I hate ordering stuff, over the internet, if there is an issue you cannot just go to the store to make the exchange . Sure hope RockAuto is easy to deal with.

Any other ideas before Tue are welcome, otherwise looks like a phone call for a RMA or however they handle it.

Sorry to hear that. I have only returned one thing to Rock Auto and it wasn't a problem. I usually order items I can wait for from Advance Auto's website because they have free shipping on orders over $200 and you can always find a 20% off promotion. If the item is bad, you can just go to the store, although no stores in my area had ANY boosters, MC, or hoses. All of the stuff for this conversion was $238+tax for me.

Let us know how you come out.

 

[Nasty]

Return claim form wants a vin, but application is for '84. Anyone think there would be a problem if I entered the vin from my '86 or should I fudge a vin for a '84?

 

[1quick6]

I don't think there would be a problem with using the stock VIN. What business of theirs is it if you are fitting a part into a different car, street rod, etc? They are probably just using it for tracking purposes but if you are saying it is defective, they might try to jam you by claiming it was installed on the wrong car and YOU somehow caused a failure. Kind of a conundrum.

 

[turboc87gn]

That is y i used the astrovan unit there are a ton more of them out there than the 84 unit if you need a replacement etc....you may have to fudge the vin cause its always a pain to explain to "normal" people when yoare doing something custom and they will swear up and down that thats the reason it dosent work...But neway good luck...

 

[Nasty]

Well the replacement booster works a whole lot better, pedal returns good and veh stops well...that is until the system starts to foam up. Seems I have some cavation issues. I rechecked/tightened all fittings and connections. Bleed the power steering system over and over. After the air is removed, system operates well and is mostly quiet (always had a very slight noise on turns). Now after operating for a little bit, it gets noisey and the fluid start to get lots of air bubbles. If I work the air out, its fine but returns again after operating. I think appying the brakes seems to be a contributing factor.

Can the booster cause this or should I be thinking of replacing the pump. When I removed the original pressure line from the pump, the fitting/valve thingy unscrewed with the line. I am wondering if that is a factor? I remember there being a seal on it, and thinking it would have been nice to replace, but just screwed it back into the pump until tight and then installed the line.

More advice is welcomed.

 

[TurboBuRick]

First I would check is connections but you already did so next I would check the low pressure feed line from the reservoir to the power steering pump. Make sure there are no kinks in the line. Starvation=Cavitation.

Another thing you can check, drain the reservoir and look inside with a light. Make sure the feed port is clear of any obstructions.

 

[1quick6]

Can the booster cause this or should I be thinking of replacing the pump. When I removed the original pressure line from the pump, the fitting/valve thingy unscrewed with the line. I am wondering if that is a factor? I remember there being a seal on it, and thinking it would have been nice to replace, but just screwed it back into the pump until tight and then installed the line.

More advice is welcomed.

I would really check to make sure you have clean paths on the return line and the line you Teed into. I wouldn't worry about the fitting unscrewing from the pump. The exact same thing happened to me, so I had to cut through the steel line with a Dremel and then put it in a vise to get the remnants of the old hose out of the fitting. I put the fitting back in the pump and tightened it good with a socket before putting the new line in. Restrictions and turbulence can be bad.

Are you sure you used the o-rings on the hoses and made sure the o-ring was still in the pump fitting you had trouble with?

This is how my Tee looks ... sort of.
I pointed the third port toward the firewall at 2o'clock (from an overhead view) and fed the return line to it from the booster.

I will be posting more pics of my install tomorrow. The above pic is credited to gmhightechperformance.com

 

[1quick6]

I just grabbed a pic of mine: