Engine/Transmission (1994 - 1998) Vacuum pump oil leak fix

[JGheen]

Just had a couple questions about fixing a small oil leak around the vacuum pump.

First, I was wondering if it is all possible to remove the Vacuum/PS pump assembly from the bottom of the truck? I noticed the PS gearbox is somewhat in the way, but if that is removed can I just drop it down instead of pulling it out from over the driver side fender. My truck is lifted pretty high so pulling it out from the top would be kind of a PITA, but if I can't do it form the bottom then I guess I will have to live with the PITA.



Also, how many seals are there for this job? I was reading up in my service manual and it stated nothing about a vacuum pump seal or PS seal, only the gasket on the back of the gear case and the o-ring that goes around the coupler adapter on the vacuum pump side.

After searching and finding some good info I am gonna get the pump seal kit either from cummins or the fixinrams site, but in the kits they include two seals, an o-ring and a the gear case gasket, so my question is, should I replace all the seals along with the o-ring and gasket or just leave the seals alone if they don't appear to be leaking?

Overall, the job seems easy from the descriptions in the service manual, I am just looking for an easy way to remove and install the assembly. To me it looks like removing the steering box and dropping the assembly down seems the easiest. I am only saying that cuz I just got my Piers intercooler boots on and I don't want to have to go through that pain again of removing the intake tube and re-installing it.



Thanks, Joe

 

[Fireman Dave]

Joe,



I have to do this too, but I haven't done it yet. I've been told that it can be done easier by not removing the power steering pump, but just tying it off to the side (and leaving the lines connected). I have the seal kit from Cummins (about $7. 50), and that's all you should need, from what I understand. Sorry I can't give you any hands on info, since I haven't done it yet. Good Luck.



Dave

 

[bcallahan]

Joe, Regarding your vacuum pump oil leak -- just completed the task on my '99 2500 quad cab. Nasty job getting the pump assembly out -- take it over the top even if you need a ladder! I removed the air/turbo ram for more room. Go with fixinrams. Mr. Gould has a very good kit with very good instructions. I recommend him highly. Mine is now nice and dry. I can park on my friends fancy driveway again!

Bud.

 

[JGheen]

Suppose I did remove the steering box which really is no problem, could the assembly be dropped down instead of going through the top? I really don't want to remove the intercooler tube, just my feeling after scaring up my knuckles real bad from installing the friggin' Piers boots. I can have my box off in less than 15 minutes which to me is a lot less painful than scarred knuckles. But if it cannot be removed from the bottom, for various reasons, please explain and if I have to do then I guess I will.



Thanks, Joe

 

[HLEschenko]

Go through the top.



I replaced the gasket that's between the front gear housing and the vacuum/power steering pump assembly. I started at 8:30 and finished at 2:30. And I had to get the new gasket at the dealer. Plus lunch.



The manual calls for removal of the assembly from the top.

The pump assembly and hoses are like an octopus. You might be able to remove and re-install the unit, but you'd be on your back looking and working up.

The gasket between the gear housing and pump assembly must be installed onto clean surfaces or you will have an oil leak.



Best of luck.

 

[JGheen]

Well, I did another search on this and most, well, pretty much all you guys who did this removed it through the top, so I guess I will have to do it that way since it seems much more practical that way. Oh well, gonna have to go get another tube of Neosporin this weekend for my knuckles. It sure sucks having bigfoot hands sometimes. :-laf

So, anything else that I should remove besides my Banks twin ram and intake tube? What about the windsheild water reservoir or I heard of some guys removing the DS battery?



Also, does anyone know about the seals? Should I leave them alone if they appear leak free or should I just hammer them out and install the new ones?

 

[JGheen]

Just found out something interesting from the guy @ fixinrams. Just ordered the repair kit and asked him a few questions about the removal and install. He said since the truck is a 4x4 and lifted quite high I can remove the pump from the bottom, but I have to leave the PS pump in the truck. I really didn't want to do that since I believe the PS pump is probably leaking as well, so I guess I will still be going through the top of the engine bay, cuz it would be a really tight and probably impossible fit to remove the assembly from the bottom. Oh well, got my hopes up until I asked him about the entire assembly removal.

 

[RSergeant]

vacuum pump fix.

Jgheen,

I just finished up putting all the new seals in my vacuum pump. Watch the video from Pete. All I can say is Pete @ Fixnrams is a great guy and has a great kit personally i would go through the top. My truck has a 4. 5 skyjacker lift and 35 inch bfg's I think the whole project was less than 1 hour from start to finish ( about my fifth time. wrongs kit from cummins etc. ) Pete explained to me that I had a older 3 piece pump. and the only kit cummins had is a 2 piece kit. Finally no more leak... Thanks Pete Oo. Any other questions I'd be glad to help.

 

[B KIRK]

When I converted my vacuum brake booster to a hydro unit, I did mine from the bottom. Power steering gear box was off, as well as the sway bar. Put the power steering and vacuum pump together on the bench, and installed from the bottom as a unit. No problem at all. I even had the auto transmission lines there also. Might have to remove your ground cable on the block as it is next to the pump. Mine was off at the time, but looks like it would be in the way. No way was I going in from the top.

Glad to see your going with Fixinrams for the parts.



Brad

 

[JGheen]

Jgheen,

I just finished up putting all the new seals in my vacuum pump. Watch the video from Pete. All I can say is Pete @ Fixnrams is a great guy and has a great kit personally i would go through the top. My truck has a 4. 5 skyjacker lift and 35 inch bfg's I think the whole project was less than 1 hour from start to finish ( about my fifth time. wrongs kit from cummins etc. ) Pete explained to me that I had a older 3 piece pump. and the only kit cummins had is a 2 piece kit. Finally no more leak... Thanks Pete Oo. Any other questions I'd be glad to help.

RSergeant, Pete had told me that I may have a hydro booster on my truck and not the vacuum pump. I am almost certain I have the basic vacuum pump, but was wondering if the booster was only installed on the 24v '98 and up trucks. Do any of the older 94-98 truck have a booster over a vacuum pump? My '98 service manual says nothing about a hydro booster and being I have never had the pump assembly off the truck before, just from the looks of it, it has to be a vacuum pump. Just wondering if you or anyone has any input on this that Pete had told me.

 

[Dave M]

Do any of the older 94-98 truck have a booster over a vacuum pump? My '98 service manual says nothing about a hydro booster and being I have never had the pump assembly off the truck before, just from the looks of it, it has to be a vacuum pump. Just wondering if you or anyone has any input on this that Pete had told me.

I just found out my 97 has the Hydroboost unit not the vacuum boost. I believe 97 was the first year for the hydroboost unit... someone can correct me if I'm wrong. And with the hydroboost unit you still have the vacuum pump to supply vacuum to heater controls etc. . but vacuum is replaced by power steering pump fliud in the hydroboost unit.



The hydroboost unit is mounted behind the brake master cylinder and is bolted to the firewall. It has power steering pump lines going to it from the power steering pump. If power steering lines go up to the thing mounted on the brake master cylinder... . vawahla. . you have hyrdoboost. Hydroboost uses the hydraulic fluid from the power steering pump to provide boost to the brakes instead of vacuum. I'll be replacing my leaking hydroboost unit this weekend with a new one from www.hydroboost.com.



Hope that helps.



Dave

 

[RSergeant]

pumps

Yes. We do have a 97 1 ton cab and chassis 2 wheel drive, it does have the hydra boost set up. look on petes site and see if you have the later 2 piece pump if it doesn't look like it then more than likely you have the hydra boost(also the hydraboost has a blue anodized part on it, and the vacuum pump doesn't). hope this helps

 

[Dave M]

Yes. We do have a 97 1 ton cab and chassis 2 wheel drive, it does have the hydra boost set up. look on petes site and see if you have the later 2 piece pump if it doesn't look like it then more than likely you have the hydra boost(also the hydraboost has a blue anodized part on it, and the vacuum pump doesn't). hope this helps

The blue anoodized part about the size of a soup can is the accumulator. This stores up hydraulic power steering pressure in the event of an engine stall condition, to provide reserve brake assist power for up to 3 applications of the brake, similar to how a vacuum booster would function in an engine stall condition.



Also there will not be any vacuum lines going to the hyroboost unit because it doesn't use vacuum. Instead there are power steering pump lines and there is no big round vacuum boost unit anymore.



Here is a link to www.hydroboost.com that shows a pic of the hydroboost unit except their accumulator is gold instead of blue:



http://www.hydratechbraking.com/products/mopar_ram/



They have a good explanation of how the hyroboost works.



Dave

 

[JGheen]

Thanks guys, well I have a hydroboost set-up since I recognized that anodized cylinder right away. And yes, I have power steering lines going up towards the master cylinder. At least the kit goes for both the vacuum pump and hydroboost trucks.

Wonder why my '98 manual refers to it having just a vacuum pump and no hydroboost anywhere that I read? Maybe it does and the section is so small on it that I totally missed it?

 

[JGheen]

http://www.hydratechbraking.com/products/mopar_ram/



They have a good explanation of how the hyroboost works.



Dave

Thanks for that link, it has some good info as well as attractive products. Just curious why does it say the boost kit for our truck is for an "R" Model?

 

[RAndrae]

Fix Web Site

Fixinrams.com

 

[B KIRK]

Reading this post is a little confusing. The master brake cylinder get its assist bolted to either a vacuum booster, or a hydroboost. If you have a vacuum brake booster, it runs off the vacuum pump. If you have a hydroboost, it runs of the power steering pump.

Regardless of which you have, you still have a vacuum pump with the power steering pump bolted to it. Only difference is if you have a 2 or 3 piece vacuum pump. The kits are different for each. The earlier models have the 3 piece vacuum pump, usually with a vacuum brake booster, The later have a 2 piece vacuum pump, with a hydroboost for the brakes. The 3 piece vacuum pump has a nipple for the vacuum hose to run to the vacuum brake booster, with a check valve at the booster. The 2 piece vacuum pump has a check valve right at the pump. The other difference is if you have vacuum assist brakes, the power steering pump has a smaller reservior, with 1 pressure line, and only 1 return line. The hydroboost power steering pump has a large reservior, 1 pressure line, and 2 return lines. The extra return line is from the hydroboost unit.

The seal is located between the vacuum pump and the power steering pump. It will only stop engine oil in the vacuum pump from leaking out. If your power steering pump is leaking, as you mentioned, that is a different problem and this kit will not fix that. It is also a lot easier to bolt the vacuum pump and power steering pump together on a bench, instead of on the truck. Working under the truck there is a good chance of not being lined up, and nicking the new seal.

The reason I converted to a hydroboost is I installed a Dana 80 out of a 2002 model with disk brakes. I got the master cylinder to go with this. It wouldn't bolt up to my vacuum booster, so I got the hydroboost unit, hoses, and power steering pump. The 2002 power steering pump bolted right up to my 94 vacuum pump.

Another thing I would recommend is to install a filter on the return line from the steering gear box. Check HERE. It's the second one down. The 3/8" for $26. 95 with free shipping. Just cut the return line, slip it in, and clamp. I use to change the steering fluid every year. When I did the conversion, the fluid that I couldn't get out I guess settled to the bottom. Looked like dirty gear oil. Big difference now.

Sorry for such a long post. Hope this helps.



Brad

 

[BigPapa]

I had good luck with these directions:



https://www.turbodieselregister.com/forums/showthread.php?t=115442



Scott

 

[JGheen]

Reading this post is a little confusing. The master brake cylinder get its assist bolted to either a vacuum booster, or a hydroboost. If you have a vacuum brake booster, it runs off the vacuum pump. If you have a hydroboost, it runs of the power steering pump.

Regardless of which you have, you still have a vacuum pump with the power steering pump bolted to it. The later have a 2 piece vacuum pump, with a hydroboost for the brakes. The 2 piece vacuum pump has a check valve right at the pump. The hydroboost power steering pump has a large reservior, 1 pressure line, and 2 return lines. The extra return line is from the hydroboost unit.

The seal is located between the vacuum pump and the power steering pump. It will only stop engine oil in the vacuum pump from leaking out.

Sorry for such a long post. Hope this helps.



Brad

Thanks Brad, that helped a lot. Went out and had a look at everything and I have 2 return lines and 1 supply line going to my hyrdoboost.

That seal you mentioned is most likely the one that is leaking as it is very wet around the adapter that mates the PS pump and vacuum pump together. It is also wet around the gear housing, so most likely that gasket is leaking as well. I think my PS pump cap is leaking and that is where the little bit of PS fluid is coming from. I guess I will know more once i get the assembly out. It does seem a lot easier to just take the whole thing out through the top. Just gonna have to remove the intake and pull the elec. harnesses out of the way.

I like the filter idea and that seems like a pretty good quality filter for this purpose. Have you had to change the filter at all yet? I would think for the price it should last pretty long.

Well, just waitin' for the parts now and should be tearing into it soon. Oo.



Oh! One other question about the system. It didn't say on the website, but that aftermarket hydroboost set-up from Hydratech, if those parts were removed, does it require to bleed the brakes after install or is it just a quick bolt up deal then just fill the PS pump up with fluid and purge the system of air by turning the wheel left and right? That sure is a nice set-up by the way.

 

[Dave M]

Hydroboost "R"

Just curious why does it say the boost kit for our truck is for an "R" Model?

On the www.hydroboost.com website, the 'R' stands for their racing version. They offer kits to replace vacuum boost with hydroboost and the 'R' version is pricey.



To get the price of the OEM version you have to email or call. My price for a new hydroboost unit for my 97 is $275. Only problem is my old one has to be shipped to them so they can remove the old firewall mounting plate, the special mc pushrod, and the brake pedal rod from my unit and put on the new unit.



I'll be doing mine this weekend, so I'll let you know how it goes.

Oh! One other question about the system. It didn't say on the website, but that aftermarket hydroboost set-up from Hydratech, if those parts were removed, does it require to bleed the brakes after install or is it just a quick bolt up deal then just fill the PS pump up with fluid and purge the system of air by turning the wheel left and right? That sure is a nice set-up by the way.

If you don't disconnect the brake lines, and I don't think you have to, then I don't see why you'd need to bleed the brakes. I plan on not touching the brakes. There is no fluid connection between the master cylinder and the hydroboost unit. There is a rod sticking out of the hydroboost unit that pushes on a cupped area on the master cylinder on my 97 anyhow. The rod from the hydroboost unit is what couples the brake pedal (thru the hydroboost unit) to the master cylinder, the way I understand it.



Look at the "FAQ" section on the website and/or email/call them. Paul is good at returning my emails. Here is an excerpt from Pauls response to changing p. s. fliud:

Hi Dave,

Timing? Whenever you are ready. PS fluid? I'd prefer you use the commonly available Valvoline SynPower semisynthetic fluid as opposed to the NAPA, though you'd be OK with the NAPA fluid too. I would like to see the system flushed before installation of the new brake assist unit. How? Yank the return line off the ps pump reservoir, cap the fitting on the pump, extend the return line as needed to reach a suitable container, fill the ps pump reservoir up then start the engine briefly - this will vigorously push the fluid through the system into the container. Next, reconnect the ps return line to the ps pump, fill pump up again, start engine, run for 2-3 minutes while steering the vehicle full right / left a few times and also applying the brakes randomly. Shut the engine off, depress the brake pedal firmly a few times to relieve any pressure in the brake assist unit accumulator. Disconnect the low pressure return line again, and repeat the first part of the procedure 2-3 times, or until you see clearer, cleaner fluid coming out of the system into your container. If you are "fast enough", you could continue pouring fresh ps fluid into the pump while it dumps out into your waste container...

The NAPA fliud referred to in the above quote is regular NAPA P. S. fliud. They approved of the NAPA synthetic Redline P. S. fluid. Guys on TDR warned me about using synthetic Valvoline SynPower even tho the Hydroboost people recommend it (or any synthetic). I'm using NAPA Redline synthetic P. S. fliud ... don't use Valvoline SynPower... that's another loooong story.



Hope that makes sense.



Dave