55.2-59 hydroboostleak

[FAKKY]

So.
Buttoning everything up still ....
Went to charge AC ...... so put the belt on and started here up.

Huge leak out of the TOP of the steering gear (R&P) near the shaft to steering.
So I have to determine if I have a bad (new) gear .... bought it 3 years back not thinking how long this would all take.

Or did I plumb high/low pressure wrong ...... etc.

PIcs.


Leaks here ^^^ out by C retaining clip.


Pump out goes to hydroboost on left.
(low pressure goes back to TOP 1 of 2 return inlets in pump resevoir.)
Then comes out the high side on the right and does down to ....



Connects here on Right side of PUMP gear.
Left side is return back to lower inlet to resevoir.

[Getter-Done]

Sub for solution.
I will probably run hydro boost.

I found this picture hope this helps.











.

[FAKKY]

The problem for me is on the R&P side ...... well I belive the top side is pretty straight forward as quite a few diagrams show that.

Spent last 20 mins researching ....... only think I could really find was this.



Says the return line is aleays closest to firewall and the largest m18 port is hig pressure.

So took apart ..... looks like I had back to front.

[FAKKY]

swapped it around .....
so the smaller 16mm closer to firewall waas going back to bottom return port of pump resevoir
Larger 18mm port is not connected to the port from top of hydroboost

Still leaks out of the same c-clip retainer ........

smh

[dsraven]

maybe this will help if you scroll down to the pic/diagram of system showing connections at hydroboost

https://www.gmfullsize.com/threads/h...h-pics.156800/


on the rack connections, the pressure line is usually the one closest to the input shaft. scroll through the pics on this link for a better idea.

http://mbmbrakes.com/content/RPP7478.pdf

[dsraven]

sorry, what rack are you using? gm or ford?

[dsraven]

if you don't have a dual return line steering pump reservoir some guys will simply install a Y in the return line to dump rack return and hydroboost return down the same hose to the pump reservoir.

[FAKKY]

Thx DSRAVEN.
Its a Dodge Dakota ~93 Rack and Pinion with a GM chevy astro hydroboost.

As best I can tell from both those articles/diagrams ....

The pressure port on the R&P is the larger 18mm one on the top left - closest to input shaft of steering.
Thats not how I had it configured when i initially ran it and noticed the leak. But it is put back that way - and still leaks.

Not sure if I blew a seal or just got a bad unit.
Thinking I might have to buy another unit and see if that fixes igt ..... I could pull it and try and remove the c-clip ...... but that whole wormgear assembly not sure how easy to put back togetehr for core warranty etc.

[FAKKY]

Originally Posted by dsraven

if you don't have a dual return line steering pump reservoir some guys will simply install a Y in the return line to dump rack return and hydroboost return down the same hose to the pump reservoir.

Got lucky - have the dual return.

[dsraven]

to see for sure which is the supply or pressure port, remove the hoses, top up the ports of the rack with fluid, then slightly turn the steering input shaft. the pressure port should suck the fluid in and the return port should overfill.
just a thought.

[mr48chev]

It's too dark to go out and look at my dualie and see how the hoses go but the pattern should be close to the same. I'm thinking that both return hoses tie in together and then return to the reservoir.

[e015475]

My truck build has been going on for 5+ years.

One of the first things I did when I started the build was to have my steering rack rebuilt. The shop said it was guaranteed for 'life'

When I started the truck recently, the rack did the same thing as yours - it pissed power steering fluid out the tower seal on the rack.

My reaction was the same as yours - I assumed I'd plumbed the thing wrong. But nope, not the problem.

I called the shop that rebuilt it and told them I'd had a rack rebuilt 5+ years ago and it leaked. They said "of course it did -you let it sit for five years and the seals need to be in oil all the time or they'll shrink back". The rebuilder says if he know his rebuild won't be driven he won't include the warranty in his price. (he sealed my rack back up 'no charge, two day turn and it works perfect, but RR of the rack was a PITA)

The rebuilder I used was Arizona Rack and Axle in Phoenix

[dsraven]

another thing you could do, if unsure which port is which, is go to a parts store and check a pressure hose from a dakota like the rack came from. that should give you the correct size of fitting for the rack input. then check how you have yours plumbed to ensure it is correct.
hydro boost pressure line from pump should go in on the engine side of the unit, pressure line comes out the other side and goes to the steering gear. the return line from the hydro boost is the hose barb connection in the middle top and simply returns to reservoir, whether "y"'d off with the steering gear return line or not, doesn't matter because they are just returning to res. as long as the res lines are big enough to handle the flow and won't create a residual pressure in the lines.
possibly, like said above, the lines were connected correctly and the rack seals are just no good.

[SunSoaked]

Seals have dried out.

[FAKKY]

Originally Posted by SunSoaked

Seals have dried out.

Thats an interesting conncept idea ....... given that its been 3 years sitting out there on truck.

Any idea if easy enough to replace or check ? Not sure if I take that C Clip off how hard to get back on.

[FAKKY]

Originally Posted by e015475

My truck build has been going on for 5+ years.

One of the first things I did when I started the build was to have my steering rack rebuilt. The shop said it was guaranteed for 'life'

When I started the truck recently, the rack did the same thing as yours - it pissed power steering fluid out the tower seal on the rack.

My reaction was the same as yours - I assumed I'd plumbed the thing wrong. But nope, not the problem.

I called the shop that rebuilt it and told them I'd had a rack rebuilt 5+ years ago and it leaked. They said "of course it did -you let it sit for five years and the seals need to be in oil all the time or they'll shrink back". The rebuilder says if he know his rebuild won't be driven he won't include the warranty in his price. (he sealed my rack back up 'no charge, two day turn and it works perfect, but RR of the rack was a PITA)

The rebuilder I used was Arizona Rack and Axle in Phoenix

Thanks e015475

Yeah being my first build --- lots of little things like this I am learning ...... wait till the end
Would you recommend them ?
Trying to decide if I just go with a local advanced auto parts deal - so I can take back easy enough.

[FAKKY]

Originally Posted by dsraven

another thing you could do, if unsure which port is which, is go to a parts store and check a pressure hose from a dakota like the rack came from. that should give you the correct size of fitting for the rack input. then check how you have yours plumbed to ensure it is correct.
hydro boost pressure line from pump should go in on the engine side of the unit, pressure line comes out the other side and goes to the steering gear. the return line from the hydro boost is the hose barb connection in the middle top and simply returns to reservoir, whether "y"'d off with the steering gear return line or not, doesn't matter because they are just returning to res. as long as the res lines are big enough to handle the flow and won't create a residual pressure in the lines.
possibly, like said above, the lines were connected correctly and the rack seals are just no good.

This is how it was plumbed originally ........ RED being high lines

I think I had it back to front at the RACK.

[FAKKY]

Looking over a new reman unit ......oreillys

Pressure Port Thread Size - M18-1.50
Return POrt Threda Size - M16 - 1.50

So had them back to front to begin with.

Top seal looks relatively easy to replace watching some youtube videos ....... but not sure where to get just that seal ..... only place I can see is ebay .... but full kit at $20 ... plus unsure if other seals also damaged etc.

[dsraven]

clean the old seal off well with some brake clean and take a look for some part numbers on it. then try the local parts place for a seal. a bearing supply place may be able to help. if you get the seal out and measure the bore and shaft size and take the old seal with you maybe even better.

[FAKKY]

Originally Posted by dsraven

clean the old seal off well with some brake clean and take a look for some part numbers on it. then try the local parts place for a seal. a bearing supply place may be able to help. if you get the seal out and measure the bore and shaft size and take the old seal with you maybe even better.

Good idea.
I'll try replacing the seal first ....... if that doesnt work go with a new reman unit.
Will keep you all posted - thanks for ideas/tips/help.

[e015475]

I'm no expert, but that's rarely a deterrent for me to offer an opinion, so here goes.....

The 'head' of the power steering rack where the shaft goes in contains a valve that directs fluid to the ram connected to the rack.

The valve has two types of seals in it - three or four external static seals that seal the valve against the housing, and some seals on the shaft to seal it against hydraulic pressure (probably some carbon face seals).

The seal you can see on the input shaft is just a simple lip seal with a spring garter in it to hold the lip next to the shaft. Essentially, this seal is just there to keep dust and dirt away from the seals that are really doing the work of sealing 1000 PSI + hydraulic fluid.

You can replace the outside seal if you want, but chances are it isn't even bad. It will still leak when you reinstall the rack, because where the rack is leaking is in the internal seals, either the rotating or static seals inside the valve. Fluid is escaping internally and this seal can't possibly hold it in.

Replacing the R&P is a pain in the ass - you really only want to do this once. Sure Autozone will take it back, but you're the guy that has to get the rack in and out underneath your truck with power steering fluid dripping down your arm into your armpit.

If'n it were me, I'd find a local rebuilder in Tampa/St. Pete that will replace the seals, test it on his hydraulic bench and warranty his work. Ask around at some local repair shops and see who they use - they know that if the rack they install is prone to problems, they'll have a callback that they'll have to eat the labor on replacing.

My work is done here. Time for a nap.

[e015475]

Well almost..........

Anticipating your next question - "How do I bleed that damned hydroboost?"

I had a really hard time getting the air out of the generic power steering fluid I bought at Autozone. I found that genuine AC Delco fluid worked best because it held less air and didn't aerate so bad.

Second suggestion is to jury-rig something to pull a vacuum on the reservoir while turning the steering lock to lock, first with the engine off and then with the truck running. I tried turning lock to lock without a vacuum on the reservoir for about an hour and was still getting a few bubbles. Five minutes with a MityVac, a piece of PVC and a sewer rubber coupling and it was done.

Love the Hydroboost (mine's Astrovan too). Brakes were a little sensitive, but after getting used to it, it works really well.

[FAKKY]

Originally Posted by e015475

The valve has two types of seals in it - three or four external static seals that seal the valve against the housing, and some seals on the shaft to seal it against hydraulic pressure (probably some carbon face seals).

The seal you can see on the input shaft is just a simple lip seal with a spring garter in it to hold the lip next to the shaft. Essentially, this seal is just there to keep dust and dirt away from the seals that are really doing the work of sealing 1000 PSI + hydraulic fluid.

You can replace the outside seal if you want, but chances are it isn't even bad. It will still leak when you reinstall the rack, because where the rack is leaking is in the internal seals

Damn. Thats a good point. Didnt think of that - now i've ordered the seal kit.
I havent heard back from the only local builder that had anything over 2 stars (reviews) ... just a remote builder in MI

"When you hook the lines up backwards you can rupture the input shaft seal and cause a leak. I would recommend having the rack rebuilt, which we can do for you. The rebuild service starts at $250, if any hard parts need to be repaired or replaced then the cost would go up accordingly."

*ouch* when you think thats not the final price (parts) plus shipping etc.

[e015475]

I was mistaken when I told you the name of the place I used.

It is Phoenix Rack and Axle, not Arizona Rack and Axle. They have a website.

Their Google reviews show 4+ stars and 130+ reviewers.

A quick glance at their website shows they pay shipping on orders over $99

If you were considering sending it to MI, I suppose AZ isn't to much of a stretch.

A couple price data points on Phoenix Rack - Paid $190 to have my Jag rack rebuilt (walk-in with the rack) there about 5 years ago. Had a quote from them recently to remove the rack from my MB, rebuild it, reinstall it and align the car for $600, same day (traded that POS without repairing the rack, thank goodness)

Another option might be some 'fresh kill' at your local junkyard. You can search "car-parts.com" for the rack by year and model in your zip code. Car-part has a Hollander built in so you'll know all the makes and models that use your rack, and you can sort the list by distance from your zip code.

I've even used the Hollander feature of car-parts to find all the models/years that use the part I'm looking for, then look on the "Row52" website for inventory at the local self-service junkyards. (I am notoriously cheap) Most of the inventory at the 'pick and pull' yards only lasts about a month before they crush the vehicle, so if it isn't leaking when you pull the rack, it is probably good.

[FAKKY]

Well I checked out a few places on the link for carparts. Generally they want at least $75 (core price). Plus its around a 30 min drive each way. So Id be better off with a reman.

I found a 1994 at the LKQ yard ..... but dont think it will work ......

Came home and pulled the rack ... as whatever I do it has to come off. I thought I would try and pull the workgear/rack to see if I could tell what seal was having issue .... and go from there about a seal kit or a just a full reman .... then I would just reassemble for a core.

Snap ring off ...... but turns out the pinion/worm housing cap is a weird 4 prong deal ... not like a big nut I have seen on other units.
Going to try and get clever or lucky ...... else just go get the reman unit.

Thought a brake caliper service unit might work ... close but no ....



https://servicems.eu/repair-of-power...ring-rack.html