B7800HST Hydraulics Question

[Gurney10]

I have a B7800HST, 2003 model with approx. 400 hrs. The 3 pt. lift works fine, except that when you engage the lift lever, it will lift some then seems to bind, if you release the pressure on the lift lever it then will lift the rest of the way as soon as you engage the lift lever. Has anyone else experienced this sort of behavior or is this normal for this model? I never noticed this happening until after I changed the hydraulic filter, even though it may have been happening and I just didn't notice it.

 

[themichelob]

Hi Gurney10- What implement are you lifting when this happens? I know when I am using my rotary cutter, if I've attached the top link too long to the upper hitch on the cutter I will sometimes get some binding. I have to re-adjust the top link so the hitch is above horizontal when connected. That's the only time I've experienced what you describe. Regards, Mike

 

[Gurney10]

About the only thing I use with the tractor is a 6ft finish mower and a 5ft bushhog. However, the lift will do this even if there is nothing attached.

 

[Yankee Clipper]

Gurney,

The 7800 has a quarter inching valve which raises and then stops at intervals. The idea was to allow small cuts with rear box blades and each movement of the handle will move the hitch only a part of the way to the top.

Other models have position control which when you pull the handle, the hitch comes to the point without stopping and then the htich quits moving where you leave the handle.

No way to convert it to postion control without some highpriced parts - if this is important, think about another model tractor.

 

[crbr]

You may very well already be aware of this:

In addition to Yankee's comment, the 7800 1/4 inching is implemented when harboring the lift control lever in close (inward toward the right leg) between the two set stops.

A full uninterrupted motion is achieved when positioning the lift control lever outward, away from the right leg.

Be sure you're not inadvertently riding the inside pull which will use the 1/4 inching mechanism. It may be that the positioning stops are not set properly, thus the sporadic motion, if indeed you are in the 1/4 inching position.

As you know, it should lift smooth and continuous in the continuous range position.

 

[DAP]

Gurney,

The 7800 has a quarter inching valve which raises and then stops at intervals. The idea was to allow small cuts with rear box blades and each movement of the handle will move the hitch only a part of the way to the top.

Other models have position control which when you pull the handle, the hitch comes to the point without stopping and then the htich quits moving where you leave the handle.

No way to convert it to postion control without some highpriced parts - if this is important, think about another model tractor.

Sorry Phil .. this is poor information for the original poster, GURNEY. It is NOT possible at all to convert a B7800 to use position control. This would require a completely different rear end to the tractor.

Additionally, the quarter inching valve on the B7800 does NOT Stop at intervals unless you completely release the lever. In fact, it will go to the top stop if you hold the lever in an engaged position.

I won't bore the others with a detailed explanation of how the valve is supposed to be operated and why it is so named as that has been done here ad nausuem.