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any 806 specialists?


rustred
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i got back to this problem again.   i can work in the field for one hr ,and my lube pressure drops in this hr. down to around 13-14 psi . cold it is around 19 psi.  tractor functions perfectly cold. once this pressure drops then it hesitates on clutch release. then will jump and take off. i pulled the MCV out this afternoon  thought maybe bad o ring in pump or else where. here is a few pic's . also wonder if the three oil tube o rings could be leaking. sure dont feel like spending 400.00 on a mcv kit just as a guess. dont think its the pump . put oil in it and tryed turning with thumb over outlet and it pushes thumb off with out hardly turning pump. what ever it is is a very slow leakage someplace. in the third pic is the only actual bad sealing i found on the middle gasket. i see scratches on those plates so some beginner must have been doing some work on it before.

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Yes if that's the problem. 

I have a 1066 that does what you are describing but the lube light comes on so lower that 5 psi hot. More in kirect drive than TA. I plugged off the hydraulic seat supply and the brake suppply and the clutch booster but it didn't matter. Went thtough the MCV and replaced the pump and it still does it so it's internal. Then last winter loading manure the TA started slipping so now I know it has to be fixed. Just haven't got to it yet. 

Sometimes the TA's leak so bad internally turning the steering wheel when hot can make the tractor stop moving. 

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13-14psi after working an hour doesn’t sound too bad. Mine has about 10psi when hot.  As Matt says if it won’t drive immediately as you release the clutch the sprag is bad. Easy check is engine not running select a 4th gear high range forward. Try to roll the tractor backwards. The spray should lock and try to turn the engine in reverse.   Get a couple of people to push on the tires to roll it back while you watch the fan. If the tractor tolls back easily it’s time for a split and t/a. 
would be worth checking drive pressures in hi and lo.   If dump valve is over adjusted the main clutch will engage before the t/a clutch pack. This will make drive take up pretty jerky. When I bought my 806 the seller said it had a power assisted clutch. Dump valve had been adjusted too much. Resting uour foot on then pedal would disengage drive (sprag was shot).   Rebuilt t/a with all genuine IH parts problem solved. (Apart from the hit to my wallet!)The old unit was in a bad way. No idea how long they ran it like that. 

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2 hours ago, Matt Kirsch said:

Yup and while you're in there may as well do the TA. Your low range sprag is not catching anymore. There should be no hesitation even if there is no hydraulic pressure.

well that makes no sense to what is happening on the tractor. as i said all is good when cold everything works as should. i have the gauges mounted in place of the light. you can start off cold with 19 psi , then as oil is warming up the pressure CREEPS DOWN , dont drop. then once its at around  the 13 psi range if you stop tractor and then try to take off it hesitates  then will jump and go. it does not do this cold when it has the higher oil pressure.  NO problem with the steering at all, warm or hot. and the other thing is tractor keeps pulling as long as you dont step on clutch and stop it, as then it will not move. so how can oil pressure have a no affect on it?

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1 hour ago, Matt Kirsch said:

You know you're near the end when this starts happening.

i also checked pressure with steering dead ended in both directions and have 1700 psi. 

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16 minutes ago, rustred said:

i also checked pressure with steering dead ended in both directions and have 1700 psi. 

and to add to this on the lube pressure,... if i KEEP WORKING , it WILL KEEP  DROPPING had it down to 5-6 lbs. so where is this oil going is my question.  you guys are giving me general answers. i heard it was not good to be working below 9-10 lbs pressure on the lube side.

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26 minutes ago, rustred said:

i also checked pressure with steering dead ended in both directions and have 1700 psi. 

That's steering relief pressure, not drive pressure. Steering is the priority circuit. Lube is the last priority so that usually goes first. The order is steering brakes Ta then lube. , That should be around 240 checked at the bottom port of the MCV. 7'8" diameter plug.  

There are probably thousands of tractors running low lube pressure since if the light never comes on it's ignored. Put a gauge on and people worry about it. 

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Just now, FarmerFixEmUp said:

That's steering relief pressure, not drive pressure. Steering is the priority circuit. Lube is the last priority so that usually goes first. The order is steering brakes Ta then lube. , That should be around 240 checked at the bottom port of the MCV. 7'8" diameter plug.  

There are probably thousands of tractors running low lube pressure since if the light never comes on it's ignored. Put a gauge on and people worry about it. 

yes i have that gage hooked up also. i have 190 psi working.

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yes , it appears that way now. i blew air in those oil tubes and it comes out the other tubes.  so  that sure dont seam right. if things are sealing in those ta and direct clutch pack it should not do that. 

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Air pressure will blow past the steel seal rings on the TA input shaft. this will allow air to come out the other tubes, like you said. They are probably worn badly.  To much air on the lube circuit will warp the seal baffle plate. The hesitation to move is your sprag clutch is getting bad, oil pressure will not fix that.

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17 hours ago, mrfred54 said:

Air pressure will blow past the steel seal rings on the TA input shaft. this will allow air to come out the other tubes, like you said. They are probably worn badly.  To much air on the lube circuit will warp the seal baffle plate. The hesitation to move is your sprag clutch is getting bad, oil pressure will not fix that.

i am trying to find out why low oil lube pressure is affecting my hesitation. i keep saying that cold everything works just fine... till after one hr of heavy pulling the deep tillage then this hesitation comes up. everytime i let the tractor cool off then its good again. no one has given me an answer to that.

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I would think that when it’s cold and the oil is more viscous it will maintain pressure to the T/A clutches. As the oil warms and thins there will only be just enough pressure to maintain drive but the moment you de clutch an try to start again there is not sufficient pressure to provide sufficient friction between the T/A clutch plates for drive. Combination of worn plates insufficient oil pressure and a bad sprag clutch. If the sprag is good it should drive in low T/A with no oil pressure at all. 

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8 hours ago, Matt Kirsch said:

The low lube pressure isn't "causing" your problem. It's a symptom of a larger issue, which is, your TA is on its way out.

I wasn’t implying low lube pressure was the cause of the problem. Just a symptom of wear and leakage. 
these tractors are getting old now so they are entitled to have a bit of wear. 

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