Yesterday I noticed a noise of sorts when we got home from a trip over the weekend. When I opened the hood, I looked in to see that I had a pulley wobbling about on the right side of the engine (passenger side). It's below the A/C pump. Is this a smog pump or some kind? Do I rebuild it and replace the bearings or buy a new one, or remove it altogether and put on a different belt?

what does this little part do and is it necessary?

Thanks,
SnowDrift

There's two things it might be. I've got the van, so mine's different. It's either the vacuum pump, or the hydorboost. Vacuum pump *may* be optional, depending upon your EGR setup. Hydroboost is very much needed for power steering and braking.

Vacuum pump. Operates wastegate and EGR on "S" engines, Operates wastegate only on "F" engines. Replace 3 on mine in 1 year. Loosen the 3 Air Conditioning pump mounting bolts, and then bracket to gain access. Up here the pumps come without Pulley and you need to pull off and press on to new one. I found out that there are 2 different shaft sizes for the taper on the pulley. Stay away from Cardone brand (reman) if you can.

i got two for sale if your interested. ones off of a 94 and the other off of a 97, both in working condition when removed.

I only had a few minutes last night to put my hands on this, but I think I have found that my pulley may be bent. I removed the belt and turned the sheave with my hand and noticed the compression inside the pump. I didn't hear anything, other than the pump making a stroke (no dry bearing sound). The sheave, though, seemed to have a wobble in it that appears to have been there for a long time, judging by the worn paint on the surface. Can the pulley be removed with the pump on the truck, or do I need to be taking the pump off to get to the pulley? I'd like to check it out to see just what is going on.

(I also noticed I'm missing a nut off of one of my bumper pads. I think this may be where the original noise was coming from in the first place.)

Thanks,
SnowDrift

Snowdrift,
Do you have any upgrades? Go to the "User CP" at the top of the page and update your signature so whenever you ask questions we already know what you're working on. Yes you can remove just the pulley. It should have a groove around the edge of where the shaft comes through. That groove fits into a puller made just for pressed on pulleys. They can be rented or bought for $15 at most parts stores. The pulley on the other hand is gonna be a big fat stealership trip for you.

Put a Turbo Master on and you can trash the vacum pump. I have the EGR engine and trashed mine no problems other than I never have to maintain the Vacum system again.......whooooo wait thats a benifit!!!

Put a Turbo Master on and you can trash the vacum pump. I have the EGR engine and trashed mine no problems other than I never have to maintain the Vacum system again.......whooooo wait thats a benifit!!!

All EGR's were not created equal. Some can get rid of them, others will have an SES light about a day after they do all that. I *think* the line begins with the difference between OBD-I and II.

Sorry, about that. I am usually pretty good about telling what I'm working on. It's a '95 K2500 HD 6.5TD "F" engine. I've got a Banks exhaust, triple gauge set, Turbo Master, Heath EPROM V1, remote FSD and a few other things.

Isn't this pump the vacuum pump for the brakes? I can't see how I could remove it, unless I'm missing something?

SnowDrift

You should have Hydroboost brakes, which use hydraulic pressure from the power steering pump for assist. The vacuum pump on your truck should have been strictly for the wastegate, and can now be removed. You will need to use a shorter serpentine belt, however.

The vacuum pump has nothing to do with the brakes on a turbo diesel. There are three 10mm bolts holding the vacuum pump in place some can be removed from the side and at least one needs to be removed by putting a socket thru the hole in the pulley.