Astro Hydroboost Plumbing - Need Help!

[Dave St]

Before, anyone says "use the search", I have already, but I can't find an answer.

I am using a hydroboost from a '95 Astro, with the Astro master cylinder and proportioning block. The block has two ports for the brake lines. I believe one uses a 10mm fitting, the other a 13mm. I need to adapt the SAE brake line fitting over to the metric sizes, so I need an adapter to go from the standard 3/16 brake line to the metric sizes. I went to every hose, fitting, and auto store in town (about 4 hours of time!) and no one has anything that will work, so I am stuck with no brakes

Any ideas where I can get an adapter? I thought that NAPA sold something that would work,but the NAPA guys here are clueless. Please include part numbers if you have them. Is there any other solution I am not thinking of?

Thanks!

 

[Madgyver]

I take it you didn't cut the lines with the original adaptors on them. Why not just use the stock EB proportional valve and use the astro adaptors to the MC and cut in new flares?

 

[NYLES]

Mad is hot on this fix......By the way!

 

[Dave St]

I did cut the lines and I have the original (Astro) adapters. I could cut in new flares on one of the lines using the Astro fittings, but the other line is larger (1/4 or 5/16, I don't have a caliper to measure); so large that a standard 3/16 line will not work.

If I eliminate the Astro proportioning valve, I will have the same problem at the Master cylinder, as those lines are the same size. I thought that the Bronco did not have a proportioning valve, but rather a distribution block.

I guess I could buy a different MC with SAE connections that would bolt up to the hydro unit. Will the 'vette MC mentioned in some of the other posts work without a proportioning valve?

 

[Madgyver]

My corvette MC is hooked up to my stock 77 proportioning valve.
I'm going to relocate the PV to another spot on the frame, This will give me more room to run the exhaust.



Check with Jeremy (cascadejohnson) He did the conversion using the complete astro set-up.

 

[casadejohnson]

Mine is from a 91 Astro and I did use the original proportioning valve. It works like a dream! I did not have the same problem with the metric to SAE conversion because my Proportioning valve had SAE fittings. Apparently, a change was made between 91 and 95. I was concerned about this issue coming up because the bolts that hold the Master cylinder to the hydroboost are metric on mine. I made my own custom brake lines so my plan was to use the metric fittings on the proportioning valve end and SAE fittings on the other end of the brake line. Another option might be to check with Summit or Jeg's, they cary the Earl's line of fittings and I think they do Metric to SAE conversions. If you want to find somthing local, I would skip the auto parts stores. I got all of my fittings from a local suplly shop that deals with heavy eqipment / tractor parts. I found them in the phone book under hydralics I think. I had the same guys make my High pressure lines and cost me less than half of what NAPA was going to charge. Hope one of the suggestions works for you.

Jeremy

 

[76Broncofromhell]

I'm using the 95 Astro Hydroboost on mine with standard 3/16's line in both ports of the MC. I used adapter fittings for the MC ports to get them down to 3/8's NF and 3/16 SAE line. I'm not running a proportioning valve however

 

[supermottl]

I got a question for ya'all (Read: Hi-jack )
I'm currently running BC's vac booster and MC with 4 wheel discs. I just picked up an Astro unit from a 93. Does anyone know if the BC MC will bolt up to the Astro hydro? If so, that would be totally easy.

Also, does anyone know what size fittings for the hydrolic lines are? pressure only...

THANKS!!

Go H-boost!!!

 

[toddz69]

I got a question for ya'all (Read: Hi-jack )
I'm currently running BC's vac booster and MC with 4 wheel discs. I just picked up an Astro unit from a 93. Does anyone know if the BC MC will bolt up to the Astro hydro? If so, that would be totally easy.

Also, does anyone know what size fittings for the hydrolic lines are? pressure only...

THANKS!!

Go H-boost!!!

The master won't be a direct bolt-up. BC uses a Lincoln master cylinder that has a different mounting hole spacing than the Astro unit.

The pressure fittings on the booster unit should be 16mm and 18mm.

Todd Z.

 

[Dave St]

On my unit the port that goes to the steering box is a 16mm O-ring style and the port that goes to the PS pump is an 18mm O-ring style.

I looked in a Weathertite catalog and found some fittings that may work for me. NAPA says they will have to order them. Once I see if they will work, I will post the part numbers in case anyone else runs into this issue.

 

[Madgyver]

Local hydraulic shop calls the fittings Power steering fittings and the size it 16mm-1.5, 18mm-1.5.

 

[supermottl]

Sweet! Thanks again

 

[Dave St]

Well, got deeper into it last night. went to disconnect the brake lines from the distribution block to the MC and found that the PO had used a reducer to go from the 1/4 port on the block to a 3/16 line. Not only that, but the lines were switched! The large resevoir was going to the rear brakes.

So, I made up some new hard lines and switched them so the large resevoir is for the front brakes, and reused the Astro fittings on the end. Got rid of the reducer, so new 1/4 inch line was big enough to use the 13mm metric fitting.

Now I have another problem: the Astro push rod is about 1 1/2 inches shorther than the stock push rod. When I hook it up I have very little pedal travel. So now I need to lengthen the rod now One problem after another.

 

[eds66bronco]

dragging this old one back up

i'm setting up hydro for a buddy and we are going to use the complete astro setup including the proportioning valve (he is running disk/drum). the brake lines were cut off below the proportioning valve. am i correct to assume the large resevoir(rear of MC) is for the front disk brakes and the small resevoir (front of MC) is for the rear drum brakes.

Jeremy, are you running disk front/drum rear and were you able to use the brake warning light wiring on the proportioning valve?

thanks
ed

 

[BG's 68 Bronco]

i'm setting up hydro for a buddy and we are going to use the complete astro setup including the proportioning valve (he is running disk/drum). the brake lines were cut off below the proportioning valve. am i correct to assume the large resevoir(rear of MC) is for the front disk brakes and the small resevoir (front of MC) is for the rear drum brakes.

Jeremy, are you running disk front/drum rear and were you able to use the brake warning light wiring on the proportioning valve?

thanks
ed

Yes you are correct. Large res. is for front and small res. is for rear.