82shovel

Need some advice here... just bought an 89 Ram that needs some repairs.

The first issue are the brakes. The PO just replaced the booster and master, but the vacuum pumps are completely gone. They tried an electric booster from another vehicle (I don't know what it came off of) at this point there is no vacuum assist brakes, nothing is hooked up, the pump they put on is inoperable.

My question is, do I replace everything with new parts using the stock setup, or should I try a different aftermarket vacuum pump setup?

Thanks!

NE frmhnd

You could try setting up an electric vacuum pump run off a relay and the brake light switch. You would need a vacuum tank too. Personally I would go to a hydroboost set-up, if i had the cash and the time.

thrashingcows

My motor is an 89 as well. I just swapped out the stock set-up for the 91.5 to 93 IC style unit, actually they used the same basic system up to 02 I think? My original still produced decent vacuum...but was making a rattling noise.

You can get the vacuum cans off rockauto, or from NAPA.

82shovel

Thanks for the replies. I ended up doing the front hoses, calipers, rotors, wheel studs, bearings seals and pads. The booster and master were supposedly recent. yesterday I checked out the rear brakes, they had been done recently I was told. I just adjusted them and put everything back together.

I ordered a vacuum pump from Rockauto, got it today and put it on tonight. I wanted to try one can first, then see if I even needed the second one.

With the brake booster connected the brakes are now really touchy. If I give the slightest pressure the wheels lock. I figured it was because I got half used to driving with no power assist (heavy pedal), but I'm not so sure something isn't wrong.

Anyway it got so bad, I disconnected the line and drove home with no power assist.

Any ideas?

Thanks

chevummins

+2 for hydroboost... Much better system and can probably be installed for what a vacuum setup would cost.

NE frmhnd

The pushrod in the master could be a little too long, maybe?

u2slow

Doesn't the booster have an internal spring to oppose the vacuum, and return the diaphragm to its neutral position? Might be rusted or fatigued.

I get fed up with vacuum stuff on my trucks. Once some of that stuff starts to give me trouble, on goes the hydroboost

thrashingcows

If that was the case his brakes would be locking up. But you could try backing off the pushrod on the booster and see if that helps. I just went through this very issue with my old 68 Chrysler wagon.

82shovel

Thanks for the replies!

I think I've got a brake/proportioning valve issue. The vac pump is doing its job. I think the brakes locking (seems to be rears first) is from the prop valve.

I did look into a hydroboost conversion. When the vac pump fails, I might switch then.

I'll post an update in a week after the brakes have been gone through. I think thats what the issue is.

~Dave