Question? Best place to put another hydralic pump

[cjohnson1]

Found out today that I have an open loop hydraulic system. Was planning to run the hydraulic pump on the Cummins 5. 9 : to run both Power Steering and brakes. Hydraulic guy (40years exp) told me it wouldn't work. Something about not building pressure with two loops.

I'm getting cramped for space and was hoping to put an on board air above the ALT. So I'm looking for alternatives. I need the on board air to run air tools for the Off Road truck repairs. I can make air some other way if I have to! But, I sure wanted the On Board air.

Has anyone any thoughts on where else or how I can mount and run another pump for my brakes system? I have Class "A" Motorhome with 90 Ford components on a John Deere Chassis. And like I said, there isnt much space in there.

I know about the tandum dual pumps for the Cummins , but then I wouldn't have a vacuum pump for the Exhaust Brake, Cruise Control and rear booster brake on the taq axle. Not to mention their price!

I'm fresh outta solid ideas. Anyone? Or is this open loop problem not a problem in the real world?



Curtis J

 

[bmoeller]

Do you mean open-center? If so, he is right. Any of the farm tractors with it that I have used, you cannot operate 2 remotes at the same time.



Do you have a pto cover on your transmission? If you do, you can find a new or used pto drive and pump from an old dump or grain truck. Can find pumps with or with out control valves built into the pump.

 

[Scrappy]

open center syst.

THe '01 cummins I have has powersteering AND hydroboost brakes with One pump. You might just have to get a later model hydyoboost brake assy.

 

[cjohnson1]

Yea I thought of that and I studied my system on my 2000 Dodge pickup for hours.

My motorhome has a hydra boost too. It's the steering box that's the problem.

I think I'm going to hook then all up together, off of the one pump, and see what happens. I may have to just plumb it different. The biggest problem with a new brake booster is this one operates three axles and has a hydro assit parking brake in the works too.

Not to mention doing a brake and steering swap will be much much more complicated, space wise, than the engine swap. It's under a bunch of bridge work below the floor. A Motorhome doesn't have a firewall with all this stuff hanging off of.

Anyone do a full brake/ steering swap? How big a truck does it stop? And how many axles are you operating the brakes with.

I'll shoot some pictures during today's wrench session and post them tonight.

Thank again



Curtis J

 

[Steve Graham]

I'm running hydraboost on my Scout, the hi pressure line goes to the hydraboost first and then to the power steering, in series. If you run the hi pressure line the same way on your motorhome I don't see why it should not work. The powersteering pumps for hydraboost have 2 return lines, one for each of the systems.



Steve

 

[tgbol]

F*rd f500s with diesels use an electric vacuuum pump. It works fine with the A/C and cruise controls, and engine brake. I am not too sure about the tag axle.

 

[cjohnson1]

bmoeller

Do you mean open-center? If so, he is right. Any of the farm tractors with it that I have used, you cannot operate 2 remotes at the same time.



I know about the tractor thing. Used to plow my aunts farm with an old Brown Tractor. It was the same way. one unit motion at a time.

The hydraulic guy was calling it an open system versus a closed system. Not absolutly sure which mine is, but he was telling me almost every automotive system is an open loop. He said the way to test it and find out would be to hook the pump to the brake or steeing and put some oil in it and start turning the pump. If it leaks out the other side then it's a open loop. Won't build up and pressure. That means (if I understand it right) that if there is another unit in parallel neither one will work as they keep bleeding off the fluid pressure. Just like a tractor. I never did find out what equipment used the closed loop system.





]bmoeller

Do you have a pto cover on your transmission? If you do, you can find a new or used pto drive and pump from an old dump or grain truck. Can find pumps with or with out control valves built into the pump.



There's another good idea. Yes the Allison does have a PTO option on it. I could hook up another hydraulic pump on it ,but , not sure if it will work all the time the motors running or would have to be kicked out of gear when driving. Guess I'll call my Allison Expert I met on another board and ask her!



tgbol

F*rd f500s with diesels use an electric vacuuum pump. It works fine with the A/C and cruise controls, and engine brake. I am not too sure about the tag axle.



Yea, I thought about that too! I need a lot of vacuum to run that tag axle. That's one of the reasons I was so happy with the vacuum pump that came on the Cummins I bought. So, not sure if the electric vac pump would work for me in this application. Not to mention the cost of the double hydraulic pump I could get for the Cummins. Very pricy. But this may be the way I have to go.



Sorry, I forgot to take pictures yeaterday until I was halfway home.



CJ

 

[CrewCabDiesel]

I would try setting it up like my 01 Cummins with both steering and brakes driven by one pump. I would think it should work fine, GM been doing it on thier diesels for years and I have seen a simular setup on some school busses.

Kyle

 

[tgbol]

Bendix make a small belt driven vacuum pump that would work for you. It is designed for diesel trucks with vauum brakes. It looks like a small blower. Could be pricy.

 

[Mtngoat]

GO to Sears and buy a small air compressor. Mount it in the back of one of your storage bays. Its easy to wire in for house or generator electricity. You then have the air you need! I wish mine had the bays you have so I could do so!



Robin

 

[cjohnson1]

Ok, here's the plan.

Going to use an elecric air compressor mounted somewhere under the bus to run the air tools and pump up tires. Less wear and tear on the belt drive this way, I figure.

Going to mount an extra hydraulic pump on the 6b Cummins to run the power brakes. In fact, it's the same pump that ran the power brakes before. I have a friend who has a 4 B Cummins with a bracket on top of the head for mounting something. He's sending pictures tomorrow of it. I'll just make one like it and turn it off of another pully on the water pump with an idler tensioner pully to keep it tight. Got two left over from the Ford motor. Since the brakes have an electric motor back system on them, I'll try it. This way, I won't have to worry about using up the one Cummins mounted pumps pressure while steering and braking at the same time. This hydraulic brake pump I'm going to mount is a remote tank type so it should be easy to set up. Remember I have a lot more room than you pickup guys. Seems the 4B bracket is just like the 6B. It mounts on top of head on the drivers side with 3 bolts horizontal and 1 verticle. The water pump pully should be a stock Cummins item. Just a little fabricating and I should be set.

The motor driven vaccum pump stays where it is cause I need all the vaccum I can get to operate the rear axle brakes, a/c doors and cruise control.



If anyone would be interested in seeing the final set up, I'll have pictures in my My photo Albumn link . Along with all the picture of other obstacle I've had to solve so far.



Thanks for you suggestions so far. Ya'll are the greatest!



Curtis J

 

[cjohnson1]

Dual water pump pully is made. Took all day to turn it, but they look good and are exackly the same size as the stock ones. Bolt on just like the Cummins factory ones.

Damn I'm good!



Tomorrow, the pump bracket. Won't waste your time. Hydraulic pump bracket is done as of Sunday afternoon. Even got a 6 groove belt on it. Will have pictures tomorrow. if anyones interested?.



And if I have time,l turn the oil pan around and modify/change the pickup tube. tomorrows job



CJ

 

[sgriffing]

Getting there

Glad to see (Hear) it's almost there.

What type of machine equipment do you have?

Brand and size that is?

Just curious.

 

[cjohnson1]

Re: Getting there

Originally posted by sgriffing

Glad to see (Hear) it's almost there.

What type of machine equipment do you have?

Brand and size that is?

Just curious.

Gunmaster 17 x 32 Mill/Lathe combo. Not a CNC but it works well for me.

It will turn some big brake rotors, No Problem.

Curtis J

 

[Steve Graham]

Curtis,

By any chance did you try the Cummins options list for this type of pully arangement?



Steve

 

[cjohnson1]

Originally posted by Steve Graham

Curtis,

By any chance did you try the Cummins options list for this type of pully arangement?



Steve

Uh... NO Steve, Didn't ever find any links to to parts options.

Remember, I'm new to these big ol smokers.

And beside the Dodge pulley is 9 groove I believe. And the one I needed to add for the hydraulic pump is a 6 groove. Soooo, I made one that would work for me. The pulley guy I talked to never mentioned the possibility of being able to buy one off the shelf,(or anyone else for that matter), so I didn't look for one.

OH WELL... ...

Curtis J



Progress Report: I took the weekend off... . After killing myself on this project for more than a year and hitting it hard every day after work till way after dark for 3 months, I was facing burnout. Just so happened all the major stuff was done, except for a few that couldn't be done now anyway. I found myself waiting for parts Thursday. I was getting cranky and very hard to live with, (so says the S. O. )so I goofed off for three days. If you can call mowing 3 acres and washing 4 trucks and cars goofing off. Not to mention all the other projects that were put on hold for 3 months. I actually wired my new garage for sound and satelitte TV. Played with the pets and shot fireworks with the neighbors till we ran outta money. Over 500 artillery shells shot. Most of the time between ten to 15 at a time. Hope everyone had a good 4th. Damn proud to be an American.