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Topic: Hydraulic powerhead dismantling (Read 703 times) previous topic - next topic

Hydraulic powerhead dismantling

Has anyone ever got this far and stripped a booster down, on my workshop it states to connect removal tool and then unwind and the cover and spring gently releases until there is no tension on the spring, the cover has released with ease but the spring has stayed where it is, does anyone know what I'm doing wrong, could it be I have a broken spring inside because there appears to be no pressure pushing the spring out whatsoever, if I push down on the piston it does spring back but doesn't seem to pop out of the body, anyone help please
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo

Re: Hydraulic powerhead dismantling

Reply #1 –
Do you have a complete parts break down schematic?

Have you tried to remove the spring?

A broken spring sounds plausible.


Google hydraulic brake booster

Tim
Tim Dianics
Pam Sapienza
Vader PupZilla Labrador Canine Beast (AKA Pup)
Columbia, MO
1996 U320 4000
2021 Jeep Gladiator, Diesel

Re: Hydraulic powerhead dismantling

Reply #2 –
Quote from: TGordon –
Do you have a complete parts break down schematic?

Have you tried to remove the spring?

A broken spring sounds plausible.


Google hydraulic brake booster

Tim

I've not got that far as to removing spring, it's like it's just stuck there, I was just expecting the spring to come out of the body as per the diagram, the lid comes off and the spring should follow with it until the pressure is off, beats me, yes I have got all the schematics for it, even says once I've removed the 2 little screws that hold in place as I release using the tool the spring will come out, so I'm a bit stumped now, I've even been looking online for a remanufacture one, cardone make them and the cross reference from the original gm number is cardone 52-9902, thing is if it is a broken spring, I wouldn't have a clue to get hold of one of those, I live in UK so can be very difficult sometimes searching parts, I have searched on Google under brake booster and the closest I've got is a complete strip down of one on a bench, but there wasn't anything on getting the spring out, I was wondering if I maybe had to push down on the spring and release something before I could remove it, but the diagrams and instructions just say put the tool on undew the 2 screws and then release the cover, exactly as I've tried to do as in the picture I uploaded with the first message,
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo

Re: Hydraulic powerhead dismantling

Reply #4 –
CARDONE Industries
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Hydraulic powerhead dismantling

Reply #5 –
Quote from: wolfe10 –
CARDONE Industries
, yeah I will contact cardone, maybe they can help, but I'm now trying to buy a new Remanufactured one, I've googled cardone 52-9902 and there are loads of sites selling them, but no one seems to have any in stock for some reason, I decided to get a new one, cause there must be something wrong with mine, I only wanted to replace the oil seal for the push rod from pedal, but had to take it apart to do the job, but the fact that the spring doesn't pop out is telling me that there must be something wrong other than the leaky seal, Im even able to push the pushrod by hand all the way in, if the spring was OK I shouldn't be able to do that, so il have to contact cardone technical support, and explain the problem I'm having to them, if it is the spring then maybe they can supply a new spring, now it seems virtually impossible to even get a Remanufactured one, or maybe I'm not looking in the right place., it's so frustrating, because that is the only  thing I need to sort out to finally get it back on the road
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo

Re: Hydraulic powerhead dismantling

Reply #6 –
Well, I've managed to get the booster apart, only problem is the seal kit I bought of ebay was supposed to be a universal kit that fits all hydraulic power heads, supposed to have every seal, well the seal that I wanted where the push rod went in from brake pedal side wasn't there either, it's now got worse because I had to disconnect the clevis from the rod to pull the pushrod back out from inside, I thought its probably never been adjusted in its life 33 years, so I was adding plenty of heat, I first managed to get the lock nut undone there is like a nurled piece just behind it that you can attach a good moll grips, and then the spanner on the nut, that went well, anyway the actual clevis I just couldn't undo, so more heat I managed to move it half a turn, wouldn't move any more, 2 and half hrs later and more heat I still couldn't get it to budge, I thought  OK get the stilsons out on the clevis with a scaffold bar on the end, and another bar over end of moll grips, suddenly it started to move, I thought I've cracked, not to be I snapped the rod inside the clevis, still I was able to get the push rod out, that's it now, I've got no choice, can't get a replacement everywhere on Google when I key in the gm number I get pictures of it different auto parts selling but everyone I try there all out of stock and waiting for cardone who remanufacture them to restock but they don't know when, personally I don't think they will restock with this particular booster, it's a cardone 52-9902, if there is anyone on the forum that could find one somewhere, I would be gratefull,  I have spoke to a technition at cardone, and it seems that if I can't get hold of one anywhere, the only option I have is to send it to cardone and they will recondition mine, but that isn't simple I can't just send it to them direct, I have to get an auto parts  vendor in the UK to send it to an auto parts vendor in the USA for them then to send it to cardone for repair, then they send it back via the opposite route back to me, Im half tempted to fly over there with part in my suitcase find a vendor get it to cardone, meanwhile I will just book into a motel and wait for it to be done, it might be the easiest way in the long run,  is cardone the only company in America that remanufacture these, or does anyone know of another remanufacturer? this is proving to be a bit of a nightmare, the only thing I need to get the villa back on the road.
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo

Re: Hydraulic powerhead dismantling

Reply #7 –
How close does this come to being workable?

52-7250 by A-1 CARDONE - Power Brake Booster
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Hydraulic powerhead dismantling

Reply #8 –
Quote from: craneman –
How close does this come to being workable?

52-7250 by A-1 CARDONE - Power Brake Booster
No I don't think that would work, it's like most of the boosters nowadays it's got some gas cartridge that charges in those type, I must have 1 of the very old type, and it's all about lining it up differently that may cause me more problems, somehow or other I think I'm gonna have to resort in sending my unit over there to be reman, and sent back to me, I've just sent an email to one of cardones vendors to see if they can arrange this for me,
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo

Re: Hydraulic powerhead dismantling

Reply #9 –
Quote from: kevo0000 –
No I don't think that would work, it's like most of the boosters nowadays it's got some gas cartridge that charges in those type, I must have 1 of the very old type, and it's all about lining it up differently that may cause me more problems, somehow or other I think I'm gonna have to resort in sending my unit over there to be reman, and sent back to me, I've just sent an email to one of cardones vendors to see if they can arrange this for me,

Thanks anyway
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo

Re: Hydraulic powerhead dismantling

Reply #10 –
Quote from: craneman –
How close does this come to being workable?

52-7250 by A-1 CARDONE - Power Brake Booster
I don't think it would match up to my master cylinder, looking at that booster you gave me a link to, looks like it's got 2 bolt connection to master cylinder, where as my master cyl has 4 bolt holes
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo

Re: Hydraulic powerhead dismantling

Reply #11 –
Do you have O'Reilly's over there?

https://www.oreillyauto.com/detail/c/brakebest-brakes/brakes/brake-hydraulics/power-brake-booster/69bab478e25a/brakebest-brake-booster-remanufactured/obh3/529902
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Hydraulic powerhead dismantling

Reply #12 –
Quote from: kevo0000 –
I don't think it would match up to my master cylinder, looking at that booster you gave me a link to, looks like it's got 2 bolt connection to master cylinder, where as my master cyl has 4 bolt holes
To the crane man, you've actually got me thinking now, if I could find a booster a newer model that they still make, I wonder if all 4 bolt hole boosters are all one size and that they could be interchangeable with several different master cylinders, what do you think, I've just had a thought, I wonder how long this oshkosh chassis was made up to into the 90s, because it's possible that they may have upgraded the booster over years on the same chassis so would have a better chance of getting hold of one, I would have to see photos and measurements of one, may have to make an adaptor plate, it gets complicated I know, il sort something in the end, thanks kev

1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo

Re: Hydraulic powerhead dismantling

Reply #13 –
Quote from: craneman –
Do you have O'Reilly's over there?

https://www.oreillyauto.com/detail/c/brakebest-brakes/brakes/brake-hydraulics/power-brake-booster/69bab478e25a/brakebest-brake-booster-remanufactured/obh3/529902
[/quote
Quote from: kevo0000 –
To the crane man, you've actually got me thinking now, if I could find a booster a newer model that they still make, I wonder if all 4 bolt hole boosters are all one size and that they could be interchangeable with several different master cylinders, what do you think, I've just had a thought, I wonder how long this oshkosh chassis was made up to into the 90s, because it's possible that they may have upgraded the booster over years on the same chassis so would have a better chance of getting hold of one, I would have to see photos and measurements of one, may have to make an adaptor plate, it gets complicated I know, il sort something in the end, thanks kev


Quote from: craneman –
Do you have O'Reilly's over there?

https://www.oreillyauto.com/detail/c/brakebest-brakes/brakes/brake-hydraulics/power-brake-booster/69bab478e25a/brakebest-brake-booster-remanufactured/obh3/529902
Well that's interesting maybe il get lucky, it might be the only one left, I've just sent them an email, probably won't get it till tommorrow now, thanks for your help
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo

Re: Hydraulic powerhead dismantling

Reply #14 –
Quote from: craneman –
Do you have O'Reilly's over there?

https://www.oreillyauto.com/detail/c/brakebest-brakes/brakes/brake-hydraulics/power-brake-booster/69bab478e25a/brakebest-brake-booster-remanufactured/obh3/529902
[/quote
Quote from: kevo0000 –
To the crane man, you've actually got me thinking now, if I could find a booster a newer model that they still make, I wonder if all 4 bolt hole boosters are all one size and that they could be interchangeable with several different master cylinders, what do you think, I've just had a thought, I wonder how long this oshkosh chassis was made up to into the 90s, because it's possible that they may have upgraded the booster over years on the same chassis so would have a better chance of getting hold of one, I would have to see photos and measurements of one, may have to make an adaptor plate, it gets complicated I know, il sort something in the end, thanks kev


Quote from: craneman –
Do you have O'Reilly's over there?

https://www.oreillyauto.com/detail/c/brakebest-brakes/brakes/brake-hydraulics/power-brake-booster/69bab478e25a/brakebest-brake-booster-remanufactured/obh3/529902
Well that's interesting maybe il get lucky, it might be the only one left, I've just sent them an email, probably won't get it till tommorrow now, thanks for your help
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo

Re: Hydraulic powerhead dismantling

Reply #15 –
Quote from: kevo0000 –
, yeah I will contact cardone, maybe they can help, but I'm now trying to buy a new Remanufactured one, I've googled cardone 52-9902 and there are loads of sites selling them, but no one seems to have any in stock for some reason, I decided to get a new one, cause there must be something wrong with mine, I only wanted to replace the oil seal for the push rod from pedal, but had to take it apart to do the job, but the fact that the spring doesn't pop out is telling me that there must be something wrong other than the leaky seal, Im even able to push the pushrod by hand all the way in, if the spring was OK I shouldn't be able to do that, so il have to contact cardone technical support, and explain the problem I'm having to them, if it is the spring then maybe they can supply a new spring, now it seems virtually impossible to even get a Remanufactured one, or maybe I'm not looking in the right place., it's so frustrating, because that is the only  thing I need to sort out to finally get it back on the road
Quote from: kevo0000 –
Well that's interesting maybe il get lucky, it might be the only one left, I've just sent them an email, probably won't get it till tommorrow now, thanks for your help
I've just uploaded another pic of the rubber boot, clevis, and locknut, would you know of any place that I could aquire these bits please
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo

Re: Hydraulic powerhead dismantling

Reply #16 –
I have 2 of power heads off of an Oshkosh. One is new. It was getting thrown away by one of the mount flanges had been broken off. I think that the broken part is still with it. I will check tomorrow and see if what I have is the same as what you need.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: Hydraulic powerhead dismantling

Reply #17 –
Quote from: red tractor –
I have 2 of power heads off of an Oshkosh. One is new. It was getting thrown away by one of the mount flanges had been broken off. I think that the broken part is still with it. I will check tomorrow and see if what I have is the same as what you need.
Well hopefully il get lucky,  thanks for trying to help me kev
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo
 

Re: Hydraulic powerhead dismantling

Reply #18 –
Quote from: kevo0000 –
Well hopefully il get lucky,  thanks for trying to help me kev
I'm going up to the villa in a bit, il send some more photos of it, I think I've sent one with the casting no. On it already, il check if not il upload it kev 8kw
1990 foretravel grandvilla, Oshkosh chassis
8.2ltr Detroit turbo