2015 Hydraulic Relief Valve Need Tweaking?

[7AcherHaven]

I suppose I am pushing about 35 hours now on my new 2015 HST with ML104 loader. Overall I am very pleased but I get the idea the relief valve may need to be bumped up just a smidge.

I have had several cases now where the x-mission will stop when under a heavy load.

When I first got the tractor, I noticed that the x-mission would refuse to go under very little load using the High setting, but I am talking about the Low setting here - and running at high engine RPM. When I asked the dealer about it, he said that this was normal for this tractor in the High setting, but that it should always spin the wheels in the Low setting.

When using the loader, I use my Tennessee River BB for rear ballast, plus my Ag tires are filled. The first time this happened I was dumping a full bucket over an embankment. I ended up creeping over it more than my comfort level liked. Anyway, reverse pedal didn't move the thing. I had to use the bucket to give it a boost backwards. I have noticed this sort of thing happening a few more times, like when heavily loaded and on an incline, and it seems reverse may be more prone to it than forward. Also, when punching forward into a loose pile of dirt, the wheels will stop (not spin), and the loader seems to give out a little early in that situation, I would expect to hear the engine load up more. The engine doesn't lose many RPM at all in these cases - seems like it's got plenty more oomph left.

So does it sound like a little tweak is in order? And if so, how should I go about it? I bet the right way would be to connect a pressure gauge to get it right.

Anyway, I may be complaining about normal behavior. And if that is the case, I still have to say I love this little thing. And I'm glad I didn't buy a bigger one - lots of stuff I have done with it would have been impossible or only partly done if it was even a few inches bigger. Had to take the BB off for some close work in my courtyard area.

I have been running industrial strength skid-steers etc, so maybe I'm just spoiled.

Regards,
Jon

 

[shvl73]

Checking it out with a pressure guage would seem a logical first step. Can you try another one out, maybe at the dealership?

 

[srjones]

Take a look at the following thread:

http://www.tractorbynet.com/forums/mahindra/93576-2015hst.html?highlight=pressure

-srj

 

[7AcherHaven]

Thanks, waiting for a reply back from my dealer.

 

[7AcherHaven]

Since I last posted, I've worked it up to 50 hours. I was gonna do the service myself, but since I've been so short on time lately, and wanted the dealer to look at it anyway, I pulled it on up there.

The gauges say the pressure relief valves are either right on or even a little high. The mechanic took it out and worked it in the test area and he saw no problems. After talking to me awhile, he says I am trying to do too much with the tractor, that the HST draws a good bit of power, and that it is normal for the tires to stop in those circumstances.

I can live with that I guess. I am the kind of guy that can push any equipment to its limits, whatever I'm driving, airplanes, cars, you name it. However, the last thing I was doing with the tractor before I took it in was trying to back up with a full bucket. It wasn't even much of an incline so I thought it would do it fine - at least it didn't seem like much of an incline to me. It was a shame to have to dump the bucket so I could get back out of there - had to dump it right on the silt fence.

I can duplicate this problem by simply sticking the bucket (I have a toothbar) in the ground as if to back-drag. If the conditions are right, even without much of an incline, the wheels may not spin. Where I'm working is fairly hard clay, and the Ag tires really get excellent traction in it.

Also, one time with a very full bucket trying to drive up a steep incline in forward it wouldn't go or spin at all. The mechanic pointed out that in reverse the HST is only 75% as efficient as in forward - which makes sense because this was a bit steeper incline, and it would have been a lot of work. Normally when driving up that same incline with a bucket of dirt the engine would labor quite a bit - even can come close to stalling out if I am using the loader at the same time.

He said he would have gone with a gear tranny on that tractor, but I wanted the easy HST control because my wife was gonna do some digging - she hasn't yet.

I sure thought we were onto something with the relief valves. Especially when I would notice the loader stop lifting with hardly any engine RPM drop. The FEL has a different relief valve anyway. I guess I got spoiled running that Case skidsteer out here so much. Heck, I 'bout shut the motor down on that thing down too, come to think of it. I'll have to go out and check that incline I was trying to back up and see just what it is.

I sure have done a heck of a lot with the 2015, and these incidents hardly slowed me down at all. I might consider a gear model if the opportunity arises, tho.

 

[SteveCornell]

This may be a silly question but you are letting up on the HST pedel right?

My 2015 HST would stall on a very steep hill with a load but if I let up a bit on the HST pedel the tractor would power itself on up the hill, I could also stall the tractor if I stuck the loader into a pile and had the pedel too far down.
There were a few times when the tractor would not pull a very steep hill with a load (usually if the tractor had been worked hard and was hot) but most of the time just letting up on the HST pedel it would power on up the hill.

I just sold mine this morning, the Mahindra has been a great tractor but it looks like my next one will be a larger Kubota.

Steve