reverse rotaton pump mount

[muddstopper]

I have two section hyd pump, I want to mount on a 7.3 international engine. Pump is 75gpm combined. shooting for 3000psi, but might be able to get by with less pressure. Anyways, the engine is coming out of a old international truck, Tranny is shot before someone suggest using the transmission to reverse shaft direction. And no the rotation direction cant be changed, without buying a lot of expensive parts. I would like to mount the pump at the rear of the engine, but I would have to build jack shafts and use belts and pullies to make that work. Second thought is to just mount the pump on the front of the engine using a short drive shaft with universal joints. My concerns with mounting at rear of engine is the possibility of slipping belts. 75gpm oil at 3000psi, would take some power to pull. I could use vee belts, but not sure to how figure out how many vee's I would need. Probably a chart somewhere on the net, I'll have to search for it. Also side loading on the pump shaft would make me worry. My second thoughts are mounting the pump on the front directly to the crank. I have seen a ton of hyd pumps set up this way, but nothing the size I plan on using. I am wonder if the crank keyway will hold up, and will the front engine bearing take the stress. I can make a mount for either end, just wondering which method would be the best to use.

 

[IceStationZebra]

That flow and pressure work out to ~130hp. You didn't state what RPM you intended to run the engine at which has a huge effect on the torque, which will determine if a key might work and what size couplings would be required. You might consider just using one coupling to eliminate the universal joints, but alignment is critical. It would also be helpful to understand the duty cycle of the pump - constant load or constantly changing.

A quick look at a Gates V-belt application guide shows that you can probably run belts off of the back. The advantage here is that you can optimize the engine RPM. Under max load the torque peak is at 2000rpm, which should be the most efficient. Another thing to consider is if the engine will get pulled down or has to start under load. Unlike electric motors, engines don't generate a lot of torque at slow speeds so they can struggle. The rule of thumb I've seen range from 1.4 to 2.0 times the horsepower of the pump.

powerstrokehub.com/7.3-power-stroke.html

ISZ

 

[bigdeano]

I've seen when they run a supercharger off the front of the engine they sometimes drill a hole in from the front of the crankshaft so it's half in the crankshaft and half in the pulley. Then they use a dowel pin as an extra key. You can probably find info about it with a little searching. I think they use a drill bushing setup to get the hole straight.

 

[muddstopper]

Pumps are a Sauer gear pump and needs 1750rpms to get the advertised flows. The smaller section of the pump will run a axial piston hyd motor.. The larger section will provide flow for a pair of 4.5in bore cyl. I intend to combine the flows after the hyd motor to provide the full 75gpm flow to the cylinders. Since the hyd motor will use a lot less pressure than the cyl, I will set it up as a high/low system by using a unloader valve to dump motor oil back to tank once a set pressure is reached. Sort of like a two stage wood splitter pump. Motor will get full flow of smaller pump section at 2000psi +/- when in use, then be diverted to unloader valve where it will combine with large pump section to provide the extra speed of the cylinders and dump back to tank when unloader setting is reached, 2000psi+/-. The larger pump section will provide full flow to the cyl at 3000+/-psi. Control vavle for cyl is a parker v70 rated at 70gpm. There will also be another double section pump, of around 14/5gpm to run other functions. The smaller 5gpm will to to run a continous conveyor, the 14gpm to run a small knuckle boom. The knuckle boom will not be in use while other operations are performed.

My plans where to run the smaller 2 section pump off the front of the engine, and the larger pumps off the rear. The smaller pump I thought I could get just became unavailable yesterday, so i have to regroup a little and look for another pump. The larger pump also being reverse rotation kind of thru a kink in my plans as well. Since this project is being built on the cheap, the pump I have is the one I will use. I can machine a stub shaft to fit the flywheel to put pullies on. Not sure if hyd pump can stand the side load of a belt drive.

 

[Whatswrong]

If I was creating this I would definitely go off the rear ,would you be able to use chain and reduce side thrust issues. Can you extend the shaft at the rear and run both pumps from there? I guess I am hesitant to run stuff off the front unless I know it has been industry proven satisfactory.

 

[Rustyiron]

Is this for your (iirc) log loader?

 

[muddstopper]

Is this for your (iirc) log loader?

Yea, this is for my firewood processor. I have been laid up for a while and just now getting back to the build.

If I was creating this I would definitely go off the rear ,would you be able to use chain and reduce side thrust issues. Can you extend the shaft at the rear and run both pumps from there? I guess I am hesitant to run stuff off the front unless I know it has been industry proven satisfactory.

What I am considering doing is making a stub shaft to bolt to the flywheel. Mount a timing belt pulley to the stub shaft to run a jackshaft, and mount one pump to each end of the jackshaft. Not a perfect setup, but cheapest way I can think of.

 

[Rustyiron]

Yea, this is for my firewood processor. I have been laid up for a while and just now getting back to the build.

Glad your back,:thumbsup: don't forget we need our pictures!

 

[muddstopper]

Paid for the donor truck today, might be a few weeks before I can get it home and pull the engine. Nothing but rain here, after a summer of drought. We need the rain, I just wish it was spread out a little more evenly instead of all at once. I have a plan for mounting the pumps at the rear, but got to make sure nothing interferes with starter location first. I have a decent cab and chassis to get rid of if anyone needs parts for a 89 international truck. Transmission is suspect, but 2sp rearend is good and has air brakes. Will have a clear title to go with it as well. I will be using the engine and related parts, including the air compressor and air tanks and the fuel tank, but everything else will probably go for scrap.

 

[oldnslo]

What size is the crank shaft? Compare that to your pump shaft. This should give you some idea on whether the crank would take the load. Very common to have a short drive shaft with u-joints running pumps in this manner.