TO-20

[rozenbag]

our hydraulics are always in motion, either going up or down. we were going to remove the top cover for a look inside and noticed a lot of sludge, so we pulled everything apart to clean. there was silicon sealer in the pump valves and the plunger/actuater in the control valve is curved. is that right. and could these be the problem?

 

[Bruce(OR)]

Chances are your control valve was gunked up and going bezerk. Curved parts? Sure it"s not bent??

 

[John (UK)]

Silicon should never be used on the hydraulics as it is not suitable for high pressures involved and as you see it can get in places that it shouldn't, always use new gaskets. If you mean the short rod between the Tee piece and the Control Valve, is the part that is bent, then that is due to mishandling and someone trying to lift off the Top Cover without detaching the Control Valve. It will not be the cause of the problem of the hydraulics "bobbing" like you say, that will most likely be the silicone sealer that is in the Side Chamber valves as they are non-return valves and they would allow the oil pressure to leak away which would cause the system to drop. You should consider changing the Safety Valve/Check Valve while you are doing all this,because if the Check Valve leaks, that too will cause the system to drop. The sludge while not desirable, will play no part in the problem you have. You should also make sure that there is no free play (in and out) on the Draft Spring at the back of the seat as this will also cause your problem, you should JUST be able to turn the Draft Spring when you have an implement mounted and in the raised position, you will probably find that the adjustment on the Plunger and Yoke through the Spring, is seized and will require freeing while you have the Top Cover removed so that you can hold the inside of the Plunger Rod. Use some grease on the threads of the Rod so that they will not seize again as you need check the adjustment regularly. Make sure that you use the correct grade of oil 15W/40 (not Diesel engine oil though) and change it every 12 months when hot after work. Fit a new felt seal under the Draft Spring and a Rubber Boot to the bottom of the Gear Change Lever to stop any water getting into the system that helps forming this sludge. It is also possible that you could have a leak on the system which you haven't diagnosed yet, you will find out when you rebuild the system. You should always locate the problem BEFORE you tear down the system as you can't always find problems unless there is a pressure in the system.
If you need more help, email anytime:- [email protected]

 

[RenegadeV8]

John UK wites:
"Make sure that you use the correct grade of oil 15W/40 (not Diesel engine oil though) and change it every 12 months when hot after work. "

15W/40 ??? I thot the TO20 used MIneral Oil in trans/axle and hydraulics.

 

[John (UK)]

You haven't been reading what has been said on here for the last two years (at least). Using a straight mineral oil in cold weather does not allow the hydraulics to work immediately, as it is too thick when cold. So we looked for a better oil and the oil manufacturers came up with this one. It is thinner when cold and retains its viscosity better when warm, so the people who needed to change the oil for summer and winter use, no longer have to do that.You possibly have never needed to do that but there are lots who did and as you can imagine it was a pain to do. The original oil that was specified is no longer available in that original form as it is no longer a straight oil, they told me that all oils now have some form of additives to improve lubrication properties and prevent wear etc. but it would still be thick when cold. Don't forget that oil was specified over 70 years ago when there was nothing else available, using the Multi-grade oils means the the hydraulics are immediately available for use when the weather is really cold and you don't have problems starting up (oil drag) or have to wait for the oil to warm up before you start to move snow. The people who have changed over are pleased with it, up there have been no complaints at all. We have had the "purists" who insist that since it was carved in stone in the Ferguson handbook all those years ago, that we must not deviate from the oil that was recommended at that time....we changed the oil and it is called "progress" They don't use the old type oil in the 35's or later and it is more or less the same system. Just try and and see what a difference it does make in a cold climate. This oil is recommended for use in all America and Canada except the very North where temperatures get extremely low, but it is still better than the original oil in these very low temperatures, just that there are a better range of oils available now. We have tractors in Scandinavia using it and they too get extremes of cold. Anyone using it in more temperate climates will not notice much difference but there is reduced wear and better lubrication with this oil because of the additives used.Don't forget that the oil in the Transmission/Hydraulics is a compromise between a Gear oil for the Gearbox and the Rear Axle and a Hydraulic oil for the Hydraulics, this Multi-grade is somewhere in between, but it doesn't get too thick, like treacle when cold.Just before you come back at me again about the word "recommended" as I think that is what you are getting at, it is recommended by the oil companies to replace the original oil type. We did use a version of this oil in the UK (still do)in the 1950's with great success AND it WAS approved by the factory too, but being as the climate in the USA and Canada is completely different to the UK, it wasn't obvious what would [email protected]

 

[RenegadeV8]

Thanks for the update. I was not aware that 15W-40 could be used in the hydraulics of the TO tractors. It gets cold here in Tennessee and i plow snow in the winter with it among other uses. Mow lawn in the hot summer.

Using engine oil makes life easier for me. Thanks again.

P.S. I'll be reporting back on the axle project in a few days and will send pics of the tool.