Power Brakes. FOR REAL!

[m880cummins]

My truck since built has had power brakes which were nothing to brag about.

The first hundred miles the pedal was really touchy (a good thing showing the vaccum assist was working) then all the sudden died. Replaced the vacuum diaphragm pumps in August because the old ones had RUST HOLES! Old ones pulled 2" of vacuum and new ones pull 22" at idle. The booster also leaks which is the reason for still weak brakes.

Over Christmas, I drove to IA and back and somewhere in Pittsburgh area the engine seemed like it was making more racket and then heard something like a big rock hit the bottom of the truck. Turns out the bolts to hold the bottom pump worked loose and the pump vibrated and broke the magnesium bracket holding it. Pump fell off and was only held on by the vacuum line so i did not lose it. Pump pushrod fell out and bounced off road and hit floor pan. Open hole made more noise but suprisingly lost less than a quart of oil in 1000 miles even with nothing to prevent oil from coming out of the vacuum pump housing. Put a small cork in the pushrod hole and drove home. Power brakes didn't seem any weaker even with only one diaphragm working.

In IA I stopped at a truck parts place outside of Moline that had a WABCO pump and hoped to score on that but when they said $150 for just the vacuum pump and $75 for a USED PS pump I couldn't walk away any faster. I pay $75 for rebuilt pumps where I work so it wasn't any bit worth it. So today, I went down to a local salvage yard that had a 6BT and scored a vacuum/PS WABCO pump setup for $50 with the lines and support bracket. I couldn't be any happier!

In this thread, I will give a detailed description of the WABCO reseal/inspection as well as PS pump interchange. I will also replace the booster and let you know the results. I feel this will benefit many....

Pictures will be promised!

Charlie

[m880cummins]

Got some work done on the boneyard pump.

Cleaned the 1/2 of grease off giving the obvious sign the seals were shot...Also notice the PS pump is pretty beat up. It's a shame because it was a remanufactured one and only looked like it was used for a short time. Both line hookups were kinked over damn yard hands don't care about a thing.



Vanes looked good and housing had scoring but was pretty minor.



I then sandblasted the whole pump and thoroughly cleaned it so it would be easy to detect even the slightest leak.





Just ordered a seal kit from ramtrans1 on ebay

Charlie

[Tacoclaw]

If you had a non IC'd pump, with the dual diaphrams, then this new pump will have an extra bracket on the bottom of it. It's made to be supported by a IC'd pump support, which has an extra threaded hole below your normal holes where it bolts to the block.

[m880cummins]

Ok, I saw on the engine at the yard there was a plate that bolted to the block and then the support bracket shared one of its bolts. Are you saying the earlier block is missing a threaded boss?

Charlie

[Tacoclaw]

No, the blocks are the same, the bracket that supports the rear of the IP has it's two normal bolt holes where it mounts to the block. On the non IC'd engines, it stops there, but for the engines that use that vacuum pump the bracket extends down farther and has a threaded hole in it that is used as a suport for the vacuum pump.

[m880cummins]

Got the pump done this morning. Went together nicely and although Gould Gear says to use their seal insertion tool I just used a socket and a vice and had no problem at all. Going to spray it off with brake clean and hit it with a light coat of good aluminum paint to prevent corrosion.













Found this too:



And just for a little entertainment. Here's a 20* cold start of my truck:

http://www.youtube.com/watch?v=Qs2gFJWL4Y0

Charlie

[m880cummins]

Sprayed it off with Brake-Clean and then gave it a coat of cast aluminum high heat paint. Then I found I can swap the pump reservoir housings that way I can use the remanufactured pump that was damaged in the first place. Took the housing off, cleaned it out, a little metal on the magnet inside but not bad. Then when I am ready to do the pump swap I can just take the housing off the NON-IC pump and put it on the IC pump. At the store, I looked up the NON-IC pump and the IC pump and found that there is no difference in the pump and the only reason for a different part number is the IC pump comes with the coupler already pressed on the shaft.





Then loc-tite the studs because these engines tend to loosen things up and its the fault for the first vacuum pump to break.



Ready to go!



Hope to put it on Friday.

[Tacoclaw]

Throw some loctite on the bolts that hold the power steering reservoir on as well. On our Fummins they rattled loose and had us on a wild goose chase trying to figure out where air was getting into our PS system from.

Looks good otherwise, I wish my truck deserved pretty stuff like that.

[m880cummins]

Very good point! Thanks!

Charlie

[m880cummins]

Got the vacuum pump on today! Swapped the PS pump reservoirs, took the old pump off, removed the throttle brackets, mounted up the new vac/ps pump and it works great!No noises, both pumps work very strong and leak free.

I decided to use 1/4" fuel injection hose with fuel injection clamps and brass 1/8"NPT fittings for an oil line. That way I can get rid of the steel line which didn't fit too well with the tight bend it had. The fuel injection hose is a working pressure of 100PSI and a burst of 900PSI so I figured as long as it doesn't rub against anything it is up to the duty.

As for the vacuum pump support bracket, there was a boss that the old throttle bracket mounted to and the support bracket fit right to the boss with a little tweaking. On the throttle brackets, I decided to redo the whole configuration for a cleaner, simpler look

Pics tomorrow!

Charlie

[m880cummins]

Picked up my rebuilt booster from work, cleaned the cosmoline off, shot it with some gloss black and installed it! Unbelievable!! Has the pedal of Mom's Honda CR/v! Almost sent my buddies head hard into the dash board! I LOVE my Dodge!



This installation info thread is complete!


Charlie