Smokeman

I was disappointed when my belt driven vacuum failed with only 60,000 km on my truck. I took the pump apart and found the cause of the failure was the stem broke off the plastic valve inside the pump. Expensive failure from a 5 cent part.

I was not able to source any repair parts so thought about options. I looked at getting a new pump from Cummins but decided to go a different route as I don't think the reliability on these belt driven vacuum pumps is anywhere close to where it should be.

I ordered a pump used by hot rodders and others that need supplemental vacuum for their vacuum boost brakes. It was the same cost as buying the replacement belt drive pump from Cummins.

Here are some pictures of the install:


The vacuum pump is installed inside the front bumper on the drivers side. It was easy to fab a bracket to hold it in place. It is also mounted on four rubber mounts. I used these but I'm not sure it was necessary.





This is the vacuum switch that comes with the kit. This turns the pump on when vacuum falls below 15" of water and turns it off when it reaches 25" of water. I like this feature as the pump only runs when vacuum is required, as compared to spinning away in "not needed" mode like the belt driven Jacobs pump.





This is a vacuum cannister I made to run inline between the pump and the Jacobs solenoid switch. It simply adds vacuum "capacity" to the system. Easy to make with 3" ABS. I threaded the caps for the fittings.

The system works like factory however the pump hardly runs at all to rebuild vacuum then shuts off. The pump is noisier than the belt driven pump (except when the belt driven one craters). I wired the 12 volt pump through a relay using switched power. All the factory Jacobs equipment remains in place (except the dead pump of course) and is utilized and operates normally.

This was a very simple install and may be an option for others interested in replacing their cratered Jacobs vacuum pump. It also allows you to go back to the stock factory serpentine belt. I am gambling that the minimal run time for the 12 volt pump will equate to much longer service life, but that will either prove or disprove itself in time.


Brian

MegaMagoo3500

Thats pretty cool. I shoulda went with something like that last month when my pump failed@67,000k. Next time I will. Great post by the way.

snoyes

Looks good. Just out of curiosity, what did you spend?

Smokeman

The pump kit was 200 bucks. The ABS caps were 8 bucks. Anything else I had laying around the shop.

troll3193

where did you source the pump from?

Bryan

Smokeman

I bought it off ebay. Search for electric vacuum pump. I think it is marketed through the Stainless Steel Brake Co.

KR6LH

When the Jacobs vacuum pump failed on my 2006, I found Smokeman's
installation thread and pictures and his later update. This is a vast
improvement over the stock Jacobs or Gould's vacuum pumps as is
reflected in all the internet threads.

The local Cummins performance shop installed an SSBC 28146 vacuum
pump in almost the same manner as Smokeman, with only two differences

- No vacuum reservoir
- The red positive line from the SSBC pump motor is connected to the
blue/purple line on the Jacobs vacuum solenoid.

Wired in this manner the SSBC pump only turns on when

- ECM calls for the exhaust brake to activate via the Jacobs relay
- The SSBC vacuum switch detects no vacuum

The response time seems to be about the same as the original installation,
the Jacobs vacuum actuator doesn't need much vacuum to pull-in.
During constant braking the SSBC pump will cycle a couple of seconds every
ten seconds, then shut off. During normal driving the ECM is not calling for
braking, the pump stays off.

When the SSBC pump is running you really have to listen for it, the pump
is fairly quiet.

I would recommend the SSBC pump be the first choice when the stock
Jacobs pump fails.

Lee

Rednax

Bookmarked.

Danavilla

I like it. Good Job. My single concern is your reserve tank. I made a similar one for my '98 to give me instant vacuum for my BD brake. I discovered that the heat near the engine coupled with the vacuum caused it to collapse. To forstall that, you might want to place it away from the engine, perhaps in a fender well or behind your bumper.

Lovemydodge06

hey Smokeman, I tryed to look at the photos of your vacuum pump install but they don't load< is there another way for me to see them?
Thanks

Smokeman

Well you got me on that one. I had them all hosted on webshots but now I cannot even get to my account there. I mounted the vacuum pump in front of the drivers front fenderwell. I had to upgrade the vacuum switch as it failed twice on me. It has worked flawlessly now for four years or so.

Lovemydodge06

Thanks Smokeman

Reelay

Me too next time!

FiverBob

This is an old post, but thought I would throw my two cents worth into the mix. I lost my ebrake two days from home coming back from Alaska. Scotty had warned me to replace the hoses before I left, but it was too late - - I had to go. I did look while in Alaska one day but had no idea where the pump was or where to look for the hoses. So, nothing got done. Incidentally, this was the first I had driven this truck without the brake operable. Oh my goodness, I was lost. What a difference trying to stop 24,000 pounds with just the conventional brakes or controlling speed on the freeway or slopes without using the brakes - - I would never run this rig without it working again.

My first input on this is do what Scotty told me to do. If your truck is a few years old, replace the hoses. Here are some tips. The vacuum pump is under the accelerator sensor right behind the fan on driver's side of engine. You have to remove the three bolts on the bracket of the sensor and move it out of the way to see the vacuum pump. The hose from it runs up toward and over the fuel filter to the firewall and the wiring harness that crosses over the top of the engine to the passenger side. Right where the hose comes up and turns to cross the engine, there is a rubber preformed 90 degree coupler to the plastic line for the ebrake. That line goes thru the wiring harness and then down the passenger side to the ebrake. That little 90 degree hose is the culprit. It had split. What I learned the hard way is you cannot operate that vacuum pump in an open condition without destroying the diaphragm. It seems it only takes a few minutes to cost you a bunch of money. Check that 90 and the other parts of the line.

Now I am home and pursuing getting that thing back up and running, I contacted Geno's garage. Seems Geno's has a repair kit diaphragm that is less than 1/3 the cost of the pump. I have not received it or completed the repair, but hopefully my warning can save some members a bunch of money. Check those hoses.

Bob