Hi All, My name is Ben, and I am a newbie to this forum. A number of friends/acquaintances have recommended this group. Here is my question: (and if this is not the right forum, please redirect me to the right place to ask this question.) I have a 1988 Cummins NTC-400 (855) engine with a Cummins PT injection pump. This is in an International straight truck that I have setup as a self loader log truck for hauling short logs. I am trying to find a way to set the RPM's for when I am running the loader. I need to have a way to govern the pump in order to keep a constant RPM, at no load, and with a load when I am loading logs. I have tried doing this with a cable and manually setting the throttle, but the pump is so touchy, that it really doesn't work, and it does not modulate in order to keep a constant rpm through the load range. I am looking for any suggestions about how to go about this. Are there aftermarket options here? Thanks so much -Ben
You need a governor for your PT pump. https://www.apexinds.com/tools/TR-1001.html This will set you right up.
Do you operate it from a seat or a standing platform, or do you swing with the loader in a cab, with a hydraulic swivel etc? On the cranes I typically set them up with a auxiliary air throttle, so I can control the throttle from the operators seat or platform. Pedal on the platform, mount the cylinder on the engine. Make the linkages will both pedals work, and you can still drive it and/ or run it from the loader, without doing any switching. The pictures are of williams controls versions, any good truck parts place can come up with them. I can take some pictures of how some of mine are mounted to give you a idea of what you need to do. Just post here if you need some example pictures. You would just need to plumb into a air supply, to the treadle pedal, then a signal line from the pedal to the slave cylinder. And make your brackets to hold the slave and the throttle linkages. I try to build mine with some adjustment in them, and always end up fiddling with them a little.
This air cylinder is extremely versatile, I've used it as a throttle control on many different applications using the pedal, you can also use a trailer control valve like the ones mounted on the steering column of a truck, or even an air toggle switch with an adjustable regulated air supply. On twitchy governors I like to add a fairly heavy return spring to the arm to smooth things out.
Thanks for the replies. The Apex governor looks like it would do just what I need. I am intrigued by the auxillary throttle pedal as well. That would definitely be doable. The rotator for the boom is operated by a set of foot pedals, so both my feet are already busy though.... I will have to think about that. Below are two pics of my truck. The first is before we had the second set of bunks on. The second is while we were still working on it.
Good looking short truck! Something similar to the apex governor is what I put on a PT pump for running a self loader. It works really well on a Cummins. Set the RPMs at 1200 and they won’t move off of that all day. That’s the only down side to a Cummins in a self loader. Cat or Mack, a standard throttle works fine. Something else I like to have is a kill switch in case you blow a main hydraulic line. It’s a bad feeling to have to run through a fountain of hydraulic oil to shut the truck off.
I would advise to stick with the idea of a constant speed governor for a log loader or maybe a 2 speed switch (idle/1200 or whatever) opposed to a variable air throttle. If you do an air or cable throttle add the governor anyway and run it through that, not direct to the "rack" or whatever you call its eqivalent on a PT system. I have worked with cranes where the operator has a foot throttle but it is more of a c-shaped deal that goes over your toe and stays wherever you put it. Sometimes you need to do a lot of boom in or out or cable in or out real fast, other times you want it at idle for fine control. But you would still want the governor to keep it where you set it regardless of engine load.
I just wanted to say thanks to everybody who wrote in on this thread. I got an Apex governor and installed it on the truck this summer. It was easy to install, and works beautifully. Thanks for all of the help.