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mrvette
04-18-2010, 12:12 AM
Got a HB unit off ebay, maybe a bit tooooo cheep, well anyway, there is a problem, of course...there seems to be NO assist, the power steering works fine, the larger input nut goes to the p/s pump, the smaller goes to the steering, and the return is obvious....

I compare to the HB on the vette and the output section looks different...

I suspect a incomplete unit or some parts been removed....

anyone have a GOOD blow up diagram....maybe showing any variations in construction practices over the years/needs....

:friends:

73 Mike
04-18-2010, 04:42 PM
Gene,

I found this diagram on line that shows as good of a schematic as any.

[Only registered and activated users can see links]

I've found a few trouble shooting links but have never seen anything on the different versions available. I do know that the internals are tightly machined and when they wear out or fail, the unit is toast.

mrvette
04-18-2010, 05:33 PM
Thanks man, I think I have spotted that page before....I spend about 3 hours last night just looking for some info on the net, found nearly nothing...

I did find some rebuild kits....but this unit was fresh black paint and my comment about missing parts is INCORRECT....in fact, the way 4 different parts houses showed it all this morning, is that I have a correct HB unit by the external pix.....I would swear the steering had good pressure/response yesterday, but maybe I goofed...at any rate jacking up the van/motor home with wheels off the ground, and circulating the steering did nothing....

but now the steering is heavy with NO power assist.....when I loosened the main pressure line to the HB unit....I expected to see fluid piss out so violently it would empty the sump in a second...such was not the case...it did come out, but very slowly.....trick IS, the damn thing was pumping fine just 2 days ago before the HB install....so that tells me some shit in the lines, but where?? what is so restricted?? is there a filter in the p/steering pumps??

there was two basic different types of HB systems I have seen listed, the first one looks like on my vette....listed at one place as for 4 wheel disc cars...interesting....the other looks like what is on this van chassis, and listed for disc/drum applications....I never knew there was any difference ASSuming the issue would be settled by the m/cyl or prop valves, or brake size.....booster?? umphgh....

so the unit I got SEEMS to be the one I need in there.....guess I lucked out on the vette, plugged it in and ran like a top right off the bat...been fine since...

so now to find the pump problem....i'ts NOT a slipping belt, with the dawg house off, I can see the pump running, and it's not slipping, belt/pump is quiet to boot....

I beginning to feel like WADE with his weird engine problems....

:bonkers::(:crutches:

73 Mike
04-18-2010, 07:46 PM
I kind of had the opposite problem with mine. I had a flow restriction in the return line that would cause the unit to self apply. I never got a great pic but the ID of the barb fitting was the culprit.

Don't know how you plumbed yours but I doubt it's the same issue since your PS is acting up. Just make certain that you have fluid and not just foam in the system. This would account for all of the ussues you've described. It took me forever to get all of the air out of mine.

mrvette
04-18-2010, 08:29 PM
The old POS vac booster had a leak in it, I was able to reduce the leak but never cure it....but knowing it was not well, I decided if to do anyting HB was the way to go....and so...

with reduced unwanted air into the system, idle is lower of course...

at 600 rpm the pump don't put out enough pressure to run p/steering....raise the idle and it's fine...but still not enough for brakes....

so I wonder if that pump can do the job...driveway on a hill, hate to test the chocks at really high idle....if the brakes don't hold....

:nuts:

wonder what a pump costs??

:clobbered:

73 Mike
04-19-2010, 02:23 AM
wonder what a pump costs??

:clobbered:

I don't think they're that much.