My 1958 D6 9U loses power after a half hour

Change the fuel filters and check the oil bath air cleaner.

[quote="daxlw"] I also have to drive it back it to the shed in first because it will come to a stop going up a hill if in second or higher. just no power.
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Sounds to me like the clutch is slipping.

Does sound more like a clutch problem since it comes on when the tractor gets warmed up. Easy way to tell if you need to adjust it is to pull the clutch in. If it snaps in with a firm pull, it should pull the load. If it pulls in easily, probably not going to pull much. It should be a definite snap in and then out when you push it back forward to disengage.

It's also possible that you have steering clutches slipping. The way to tell that is when the tractor won't go, look at the drive shaft (oil clutch models) under the floor plates and see if that keeps spinning or stops. If it keeps spinning and the transmission is in gear, then the steering clutches must be slipping.

Steering clutches tend to slip worst in low gear under heavy loads while the main clutch tends to slip worst in higher gears under load.

If it's the engine that's slowing down and won't pull the load, try to see what the fuel pressure gauge on the filter housing is showing. If it works and it's in the red, then change fuel filters. NAPA 3164 (takes 4 of them and no gaskets for the cover), or you can order from CAT. Look under the fuel tank at the rear of the tractor, left side and you should see a shutoff valve there in the fuel line. Turn it 1/4 of a turn with a 7/16 or 3/8" open end wrench, can't remember which it is. Then remove the filter top cover (4 nuts) and lift the top off. Pay attention to where the bleed valve is pointing so you put it back on right when you're through. You should be looking at 4 springs and retainers that mount the filters below the plate you're looking at.

Lift whole top plate off and CAREFULLY compress the springs and remove the retaining pins from the square filter holder rods. They are relatively delicate items, handle them carefully. The last time I changed a set of these filters, I found that one filter holder had broken and dropped the filter into the housing and I broke another one just handling them. The square shaft appears to be threaded into the round piece at the bottom. That is where mine broke, just at the threads on the bottom. I had some spares, so I didn't do a redesign with threaded rod, but I think it wouldn't be too difficult.

Before you install the new filters, drain the housing (cap on nipple at the bottom) and get rid of as much sludge and water as you can. Won't hurt to wash the housing a bit with gasoline or clean diesel. Replace the drain cap and pour the housing nearly full of clean fuel. Ease the filters down into the housing and button everything up. That fuel will be filtered when it comes up around the square filter retainer shafts to the top of the plate.

Turn fuel back on under tank!

When you crank up the pony motor or get ready to start the engine, HAVE THE THROTTLE CLOSED, and the bleed screw on top filter cover open. turn engine with filter bleed open and throttle closed until you purge all air out of the filter housing. Once you get that closed, you should be able to start the main engine without bleeding the fuel pumps or injector lines. If you started trying to crank it with air in the lines and the throttle open, you may have to bleed the fuel pumps and injectors.

Good luck!

Ya if the engine rpms stay up but the tractor doesnt move or slows then it does sound like the main or steering clutches may be slipping. The main clutch should pull in with a hard snap. check the steering clutch release arms if they have some freeplay if not it can cause the clutches to slip or it might be time for new clutch dics.

D6

I agree with Rome. If the RPM's come down with the power loss, it's not the clutch. If they RPM's come down, change the fuel filters, clean the fuel tower, and check valve on the fuel system. Service the air breather. If it's an oil bath type, wash the screens out too. My
D6 lost power as you discribed. Changed both the air and fuel filters and it came back to life again.

If the RPM's stay up and the tractor slips in the drive train, then look at the clutches.-glen

One other little thing to check would be the fuel tank lid, make sure it is venting properly. I have seen that side hole pluged with a mud dauber (sp) nest, causing fuel pressue to drop over time , thus lost power. Just a thought.

Bruce P