Ford 7810 Transmission problem

Hi Guys,

I am trying to problem shoot a transmission problem on a 7810. I havent seen it yet, it is my uncles. This tractor has the 'dual power' box between the clutch and main transmission. I have been told that when the engine is started and its put into gear, nothing happens.

Some things I observed when last using it:
When driving along not necessarily under load, there was occassionally a shudder in the front wheels, more like a jerk and a scary noise as it appeared the front wheels were thrown into rotating forwards. I 'think' it wasnt in 4wd at the time?

Additionally, when the pto came under heavy load, the pto dropped out and stopped. This may be unrelated. I would add that also when under very heavy load smoke was observed coming from the back of the tractor, exiting somewhere near the top link. Again, maybe completely unrelated.

Any suggestions for problem shooting the transmission of power from engine to wheels is appreciated. It did have a new clutch 12 months ago.

Thanks very much for any suggestions.

Kind Regards, Iain.

I would say that the PTO clutch is toast and maybe the DP as well. The place to start is checking hyd. pressure. Inadequate pressure will allow the clutch packs to slip and burn. You will need a gauge adapted into an hyd. hose or coupling to plug into one of the remotes. You will need a manual to tell how high the pressure is supposed to be. There is also likelihood that the primary clutch is slipping, most likely due to oil leaking on it. Repairing it will require a front split. PTO clutch can be accessed under the rear cover.

I agree. Low clutch pressures would also allow the 4wd to start engaging causing the front wheel shudder. 4wd is spring engaged and hydraulic release.

There's a loss of pressure somewhere in the Dual Power/PTO/MFWD clutch circuits. They are all supplied by a second pump section on the rear of the main pump with the pressure regulator in the PTO control valve. Your first step is to get a 300 psi pressure gauge and get it fitted to the tractor. If it's got a newer pump it will have a 1/8" NPT plug in the manifold of the pump that leads to the DP/FWD clutch supply lines on the bottom of the pump. If it doesn't have that plug you will need to tee into the DP supply line to get the pressure reading. What you do from there is test with the engine operating at a fast idle... you want 160-180 psi although 150 is probably fairly normal. You test with the DP in high, then low... with the PTO engaged, then disengaged and then with the MFWD engaged and disengaged. Try all various combinations. If a 10% or more loss of pressure is observed in one of those variations that is not observed otherwise then you can assume that there is a leak in said circuit when it's engaged. You will also notice pressure dips when something is shifted but it should recover momentarly. You should also look at the pump body to the rear of the main filter... you will see a plastic square plug. This is the strainer/filter for the PTO pump section. Remove this and clean it. At this point you're probably going to find a LOT of crap in the oil.
If it's been run this way for a long time then you're probably looking at a major teardown to reline the DP, the mfwd and PTO clutches... and clean the accumulated buildup of filings and clutch material. It's also possible that if the brakes are worn down that their material has contaminated the oil to the point that it's blocking the intake strainer continously...
If it's got a system wide loss of pressure look directly to the strainer. If it's got no pressure period it may also have a sheared spline on the PTO drive hub at the flywheel.
Remember, pressure test FIRST. THIS IS THE SINGLE MOST IMPORTANT STEP YOU WILL TAKE IN THIS REPAIR.

Rod

Hi
Sadly sounds to me that if you can't fix it all your self it's time to shoot it and go find another tractor :-( Thats hopefully better .
This little lot doesn't sound cheap for Parts and shop time at current rates if you can't do it.
Regards Robert

Guys,

Thanks so much for your comments. I have some partial new information but will await for the final comments about the machine which may help in pinning down the issue.

As a start I think when left to sit for a while where it stopped in the paddock, the tractor was then able to be driven back to the shed.

I'll get the exact info soon and hopefully some of you very knowledegable guys might be able to add some further comment.

Thanks so much.

When you get more info repost on the Ford forum... Discussion will be more focused there.

Rod