2nd Gen Non-Engine/Transmission PAC Brake issues

[Wyomingcowboy]

I have a Pac brake that's having issues.....I can manually make it work by pushing the button on the little numatics control under the hood, but the rocker switch in the cab works very sporadically at best. I am getting voltage to the box through my in cab rocker switch. but the numatics control box acts like it's very finicky. I lubed up the brake real good and when the box decides to work, the brake has no problems turning on and off. Do I need a new numatics box? Is there some way to clean this one?
Another thing I noticed is that there is very little vacuum being produced by my vacuum pump. I don't know how much is really there or how much I should have, but I can barely feel it pull on my finger when I place it over the hose end.

 

[SnoKing]

Is your cruise control working ok? The vacuum ones under the drivers battery tend to rust out in some areas of the country more than others. By a vacuum gauge and start checking things out. The line from the pump comes up the top of the fire wall on the drivers side. SNOKING

 

[Wyomingcowboy]

I fixed the issue for now.....
I pulled apart the switch and blew a little carbon out with some carb cleaner and so far so good. It wasn't real bad but had enough carbon in it that it was kind of sticky. As for the vacuum, I checked on All Data and the pump is supposed to put out 25+ in. If it consistantly produces 24 or less it's supposed to be replaced. The most I could get out of mine is 23ish....... BUT, all the vacuum accessories work good enough for now. I priced a new vacuum pump from Oreilly's and they want $340 so I'll get by as long as I can with this one.

 

[BDaugherty]

Do not consider an aftermarket vacuum pump. It is guaranteed junk. Rebuilding the stock one is the only way to go.

 

[klcammie]

Do not consider an aftermarket vacuum pump. It is guaranteed junk. Rebuilding the stock one is the only way to go.

It is not that hard to rebuild. Go to fixinrams.com for the kit and new vanes. My advice if you do this yourself remove vac and power steering pump as one unit.

 

[crabman]

Do not buy a pump from auto parts store. Check the above links or go to YouTube and do a search on dodge ram vac pump repairs. The hardest part is the access, it is best to remove the LF tire and splash panels. I have found out that removing the D/S battery & the metal intake tube gives you excellent access & a clear line of site to most of the fasteners & hoses.
Here is a excellent link on how to rebuild one.
http://www.youtube.com/watch?v=vJhR48a-9R8

 

[Wyomingcowboy]

If I have time this winter I'll give it a try

 

[RBeard]

Cowboy,
Pac-Brake offers a tech support bulletin on the maintenance of the Vac. switch. Go to their web site and download/print it and follow their directions. I did mine and it fixed my issues.

 

[MLee]

Geno's also has the rebuild kits.

 

[MLee]

Was also wondering about VANE replacement. How important, or is it needed.
How about an auxiliary tank for more vacuum volume? Checked my vacuum and its maybe marginal @ 21"/22" or so. I have 158K on the truck now.

 

[SnoKing]

I have a Banks EB that works off the trucks vacuum system. Only trouble I have is every few years I have to clean the vacuum solenoid and lube the o-ring on the little plunger in the end of the solenoid. Tuner cleaner with lube seems to work file. This little piece that I call a plunger is on the other end from the actual vacuum switch end. It appears to be there to allow the solenoid plunger to move when activated without creating a low pressure area behind it. Or it is there so that you can manual push the plunger to test operation of the brake. At any rate when it start acting up I take it apart and clean everything and it then works fine for a few more years.

In this photo your can see the solenoid on the firewall above the left left of the BHAF with two blue vacuum hoses connected.SNOKING

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[klcammie]

Was also wondering about VANE replacement. How important, or is it needed.
How about an auxiliary tank for more vacuum volume? Checked my vacuum and its maybe marginal @ 21"/22" or so. I have 158K on the truck now.

When you pull vac pump apart you can check the vanes, mine needed a little cleaning [196k] when I did mine. One thing you can also try is putting a little 3n1 oil in one of the vac lines near the pump, this will lube the vanes
. Maybe one or more are sticking.

 

[ARARAR]

If you had a vac problem you would also have a boost problem. A while back my pac brake started work sporadically and I also cleaned the solenoid and it worked good for a while but I just ended up replacing it yesterday and it works fine now. If you get it from pac brake there around $98.