Cat 239D Down Pressure Issue

[onehunter]

Hi, I recently purchased a 2018 Cat 239D and I believe it may have a function issue. I am new to Cat skid loaders and perhaps this is just operator error? All of the hydraulic operations function properly, except for boom down pressure. If I tip the bucket so the cutting edge is down, and then lower the boom until the tip of the bucket hits the ground, I cannot lift the front of the tracks off the ground. I have tried toggling the stick fwd and backwards, but that does nothing. If I have the boom all the way down with the bucket flat to the ground, I can tip the bucket and easily raise the front of the tracks off of the ground. The only way I have boom down pressure is to roll up on the roller button as I move the RH stick fwd. Am I doing something incorrectly, or is this just how Cat loaders work? Seems odd to have to do 2 inputs to get boom down pressure. I appreciate any feedback. Thanks Al

 

[flyerdan]

I moved this up to the Cat forum hoping that someone will have an quick answer.
Not familiar at all with it, but it sounds like it could be a float mode issue. Check your operator manual for float function.

 

[creelinecat]

I moved this up to the Cat forum hoping that someone will have an quick answer.
Not familiar at all with it, but it sounds like it could be a float mode issue. Check your operator manual for float function.

ya check the float/detent button, likely in owners manual

 

[onehunter]

I moved this up to the Cat forum hoping that someone will have an quick answer.
Not familiar at all with it, but it sounds like it could be a float mode issue. Check your operator manual for float function.

Thanks for the response. The float button seems to be working fine. When its depressed the boom will float.

 

[ianmcolo]

When you lift the boom arms all the way up, then hold it there, do the engine rpms drop? You might want to compare the rpms to the tilt function. If they RPMs do not drop that means hydraulic pressure is not building up inside the cylinder which means oil could be bypassing past the cylinder piston. Easy fix-reseal the cylinders. Another way to check this is also leave the boom half way up and see if it drops with in an hour or so. If it does again it might be oil bypassing cylinder piston. Does your machine seem to pick up heavy loads like it should? If the problem is not in the cylinder in might be in the boom section of the control valve. Hope this helps.

 

[onehunter]

When you lift the boom arms all the way up, then hold it there, do the engine rpms drop? You might want to compare the rpms to the tilt function. If they RPMs do not drop that means hydraulic pressure is not building up inside the cylinder which means oil could be bypassing past the cylinder piston. Easy fix-reseal the cylinders. Another way to check this is also leave the boom half way up and see if it drops with in an hour or so. If it does again it might be oil bypassing cylinder piston. Does your machine seem to pick up heavy loads like it should? If the problem is not in the cylinder in might be in the boom section of the control valve. Hope this helps.

Thanks for the feedback. With the boom fully raised or the bucket fully tilted, and held in those positions, the engine rpms dropped by around 100. When I shut off the machine, with the boom elevated, it starts to slowly drop almost immediately. As far as picking up heavy loads, I can raise a full bucket of sand at idle. The hydraulics seem very strong. You mentioned resealing the cylinders, if the seals are bad, wouldn't that mean they should leak? My machine is nice and dry with no leaks anywhere. Or can a cylinder not leak, but also not hold pressure? Thanks Al

 

[foton]

Thanks for the feedback. With the boom fully raised or the bucket fully tilted, and held in those positions, the engine rpms dropped by around 100. When I shut off the machine, with the boom elevated, it starts to slowly drop almost immediately. As far as picking up heavy loads, I can raise a full bucket of sand at idle. The hydraulics seem very strong. You mentioned resealing the cylinders, if the seals are bad, wouldn't that mean they should leak? My machine is nice and dry with no leaks anywhere. Or can a cylinder not leak, but also not hold pressure? Thanks Al

yes cylinders can and do leak internally, and they usually are not to pricy to rebuild , but can take some specialized tools to take them apart.