Engine/Transmission (1994 - 1998) Lessons learned rebuilding vaccum pump

[A-bomb]

First of all let me say I have over 25 years of experience working on aircraft. That said this is not an easy of a job as most poster make it out to be. I thought I would add my thoughts on this job for future searches.

1. Make sure you remove the driver side battery and intercooler tube. This makes for easier access.

2. You need metric and SAE open end, box end, and wiggle sockets to make things easier to dissasemble.

3 I had to split the power steering lines with a knife to remove them. The original paint had cemented the lines to the fittings. Fortunately there is enough line to reinstall without replace.

4. The oil line and fitting were seized in the pump (Line PN 3923084, fitting PN 68138). I needed to replace the line after removal. I called Cummins Rocky Mountain (303-287-0201) in the afternoon and I recieved it the next morning at my house via Fed-EX. Cudos to Cummins!

5. Order the seal kit from www.tricountymachine.com (John 860-642-7033) a TDR member for $24. They were prompt and safe with the order.

6. You do not have to remove the oil pressure switch as mentioned in the service manual to get the pump out. However, you do need to remove the connector.

7. Get a Quart of power steering fluid before you start.

8. After reinstalling the pump I discovered the oil line needs to be very tight in order not to leak. I understand why it was seized up when I removed it.



Good luck.

 

[SMorneau]

I thought it was fairly easy and I wouldn't want anyone to be afraid to try it. There is a lot of money to be saved doing this one yourself. I also had trouble with the line but I used a crowsfoot wrench on an extension to take it off at the T fitting on the block. I also replaced the fitting but not the more expensive line. I had both on hand ahead of time just in case and I returned the unused parts. I also purchased an 18mm flarenut-crowsfoot wrench to remove the power steering lines at the box (hard to find item). I also had to cut the return lines but I planned to replace it anyway so I didn't give it a second thought. All in all this job was much easier than I anticipated but I know things can get bad real quick with any job.



I will add if there is a burr on the drive dog of the pump when you it apart you will need a new seal because you will nick it. You will want to remove the burr before assembly or it will nick the new seal.



Anyway, I Hope you got it sealed up now. Mine is still bone dry after about 60k.



Scott

 

[A-bomb]

Scott,



Yes it seems to be bone dry. The metric crows feet are hard to find. I also used a set of crows feet to tighten the fitting after install. Also you are right about saving money doing it yourself. However all the stuck lines are what made it more difficult than what I had anticipated. I just wanted folks to know ahead of time before they start saying bad words taking things apart after looking at this site and thinking it is very easy to do. You are very correct that some seemingly complicated things are easy, and easy jobs can go south fast -especially when you have seized studs, nuts, hoses, fastners, or bolts. You never know untill you start the job.



I think there are a lot of very experienced mechanics on this site that would consider this a very easy job. However, there are a lot not so experienced people on this site that may not have a lot of tools or enough experience to know they can cut lines and replace parts as needed to get a job done. It could be a scarry experience. We've all been there at one time or another regardless how expereinced we are.

 

[JGK]

I had to do mine twice as I had a serious oil leak between the 2 pumps AFTER I reinstalled it the first time (I was actually replacing a bad PS pump, and replaced the vacuum pump seal at the same time).



The first time I removed the two as an assembly and replaced the seal on the bench. Yes, the oil lines do seem to be glued to the metal tubes and had to cut mine as well. That was the only fight I had. Flare nut wrenches are the only way to go on that big line on the back of the PS pump.



The second time I decided to do the short cut. I separated the pumps after pulling the vac. pump free from the gear case, thereby leaving the PS pump lines all connected. It's a bit more stress, but actually not too bad. Not nearly as messy, either. It helped to have just taken them apart so I knew how they went together.



Apparently, when I put the 2 pumps back together the first time, I pushed the seal back out of the bushing! That was the cause for the leak. The second time, I put a light coat of non-hardening gasket sealer on the outer surface of the seal to sort of "glue" it in the busing. It all went back together just fine, though its a little harder putting the pumps together working over the fender.



I did remove the intake tube and horn, but I didn't remove the battery.



A pain, but still a heck of a lot cheaper than what the dealer charges.



-Jay

 

[BigPapa]

I just got my kit from Tri-county yesterday. He told me to seperate the pumps and not undo the PS lines. What "special" tools will I need? More detail the better!



Thanks!

Scott

 

[Bill Lins]

He told me to seperate the pumps and not undo the PS lines.

Good luck if you try it that way- there is BARELY enough room to get the vacuum pump out and it is a total PITA to get the pump dogs lined up on reassembly. Much easier to pull both pumps as a unit. I had to disconnect the P/S return line up by the Hydro-Boost unit & pull the line along with the pumps.

 

[towner]

I've done three for people now... . I split the power steering pump and vacuam pump in the vehicle... You have to be careful putting pump back together but I didn't do any extra parts removal and did the last one in just over an hour.

 

[DavidC]

FYI

Sears has a 10 piece metric crowsfoot set on the shelf from 10 thru 19, Craftsman set. The number is 4363.



Dave

 

[Jim Fulmer]

Good luck if you try it that way- there is BARELY enough room to get the vacuum pump out and it is a total PITA to get the pump dogs lined up on reassembly. Much easier to pull both pumps as a unit. I had to disconnect the P/S return line up by the Hydro-Boost unit & pull the line along with the pumps.



I did it this way also, thought it was much easier to separate the two on the bench.



Jim

 

[BigPapa]

Come on guys, tools, tools, TOOLS! What do I need? I've seen mentioned crows foot(what sizes?) and line wrenches(what sizes?). I have to do my work in the evenings and I can't just run down to the store and pick up a wrench. Any help would be appreciated!



Thanks,

Scott

 

[A-bomb]

Utility knife, pliers, drip pan to catch fluid, rags, the following open/box/ratchet wrenches, crows feet, and or wigglers : 7/16, 5/8, 15mm, 14mm, and large deep socket set to push out seals: 9/16, 5/8, 7/8, and 1, if I recall correctly. Ball pein and dead blow hammers, cleaning solvent, a vice, a table or bench. Basicly you need a set of metric and standard crows feet,wigglers, wrenches, and deep sockets, as well as a 4" and 8" extension for your ratchet. The pumps differ on different models of trucks. So, I could not be sure to say what exactly you may need for your pump. If you dont already have any of these tools, get the entire sets, not individual pieces, as it is a lot cheaper and you will probably use all of them in them again in the furture. Tools are not cheap, but they are cheaper than having the work done and they are an investment, not a cost - at least that's what I tell my wife. She dosent argue when I come home with $200 in new tools, which doesnt happen too often anymore, but use to happen all the time.

 

[vssman]

I thought it was pretty easy when I did mine. Pulled both the PS and vac pump together as a unit. I'm going from memory but I removed one PS line that has a fitting on the rear of the pump at the pump and the other from the steering box where it's fitting is located. Getting one of the bolts back in when putting it back on the truck was the hardest part. Took about 1 hour - again from memory...

 

[SMorneau]

No question, I would pull the assembly and do it on the bench. I had to do mine twice and by the second time it was easily under a couple of hours altogether. My arms are short and I don't think I could do the seal replacement in the truck. I also recall there are two diffent types of vacuum pumps and I think the stlye I have requires you to take the back side of the pump off to drive out the collar and seal. I sure would not want to do that in the truck!



The oil lines and PS lines are not a big deal if you don't bugger them up with the wrong wrenches. Removing the intake plumbing only takes a minute or two and gives you plenty of access to remove the assembly from the top.



Scott

 

[JGK]

SMorneau,



I think you may be a bit confused. You don't actually do the seal replacement with the pump down there by the engine. You pull the 2 pumps away from the gear case still bolted together. Then you remove the bolts and separate the pumps. Now you can pull the vac. pump out, split it, and replace the seal on the bench. The PS pump just sets there loose but still all connected up to the fluid lines. It's just a little tricky aligning the dogs on the PS pump shaft with the X-disk in the vac pump and getting the two put back together.



I, too, am short (and won't be mistaken for a direct decendant of the chimp family by checking the length of my arms ). But it really wasn't that bad.



Wrencher's choice!



-Jay