The Caterpillar 248 skid steer loader was introduced in 1999. Production of 248 ended in 2004; it was replaced by the Caterpillar 248B. Cat 248b Skid Steer Operators Manual Cat service manuals, parts manuals & maintenance manuals, skid steer loaders; quickly identify and order genuine cat parts to keep your machine running at peak.
I'm having my first real problem with my Cat 248 since I've owned it. The axillary hydraulic circuit is activating on its own for some reason. When I run my 4 way bucket, it opens itself without pressing the button that is supposed to do that function. I can't close the bucket up again until I press the button that is supposed to open it, it kind of cancels whatever signal it's getting to open, then I can close normally. I currently have to disconnect the hoses to the bucket to load material, otherwise the bucket opens whenever it feels like making a mess of things. Because I have to seemingly cancel the 'open' circuit by pressing the 'open' button, I'm thinking there is a problem in the computer somewhere that controls this function.
I would think if there were a short in the wiring, it would not respond to the 'open' switch as it does. Any ideas on what this may be and where I should start looking for trouble?
Steve, I would be considering the switches in the pilot stick. This an electric over hydraulic circuit and dirt or moisture would be the culprit I expect. I haven't had cause to look at the actual circuit for this but, when I had the 246, one of the relays for the ECM got some dust in it and played up once. I got the machine going again by simply waggling the wiring where it went into the relays.
Cat 248b Skid Steer Bucket
These are the big relays on the upper right side of the engine bay in the B series. I have the thumb roller in the 248B and haven't had an issue.
I think I'll have a look in my manual tonight. The one we have at the quarry had a similar problem where when you hit a bump the engine would lug down.
Hit another bump and it would speed up. It had no Aux.
Attachments, just the standard bucket. After much troubleshooting they found one of the Aux. Buttons to be defective. The mechanism in the button that actually makes the button go 'click' when you press it broke and the button was just kinda in limbo. Since there was not an attachment on it the hydraulic strain would lug the motor down.
I was not there when they took apart the control so I don't know what is in the joystick. They replaced the button though and it fixed the problem. If there had been an attachment on the machine the button would of activated it when hitting a bump. Just a thought.
On edit: I should also add that the yellow rubber covers were still intact. They are never used although they are slightly worn from people resting their thumb there. This was at around 1200 hrs. Click to expand.Are you lowering the safety bar in the cab, if equipped? Is the parking brake actually releasing? Is there build-up/debris under the seat?
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Been awhile since I've been on ours but I don't think the seatbelt had to be buckled. You just need to be sitting in the seat with the safety bar down and the parking brake released.
If you're doing all that and its still not working then you might have a problem with one of the switches or interlocks. If you want to rule out the seat switch then you can bypass the switch by connecting the 2 wires directly.
CAUTION: I do not recommend leaving it this way, if the switch is the problem, because you are bypassing a safety feature. Hope this helps.:thumbsup. On my 236 i was using a rock hound on a yard when i lost all hydraulics and power to the wheels. Motor ran fine but no power anywhere. There are two bolts that hold the pump to the motor, well they both backed out and the pump fell. There is a plastic disc that bolts to the flywheel that the pump splines in to.
When the pump fell it eat the splines out of the plastic disc and lost every thing. I think the parts where around 300-400 bucks but had a friend that works for cat install it, i think labor was 700-800. He had to take the motor out to reinstall.
I home it is something simple but if not this may be the problem.