Hydraulic issues

I got enough snowfall today to require hitching up the snow blower to clear the driveway. It's fairly cold, probably -15 C with the windchill. The tractor was kind of grumpy but eventually started but then started spewing hydraulic fluid out of the reservoir vents. See attached picture.
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It's a B434. I have done some looking at the IT shop manual but can't decipher how the hydraulic fluid would return or bypass to the reservoir.

If the tractor is off, the control will keep the lift arms at a set height, but the minute I start the tractor, it's as though I have fed the lift arms V1agra.....
 
Ah that ain't hyd oil , that is more water then oil and i do believe ya really need to do some much needed fluid changes all thru the tractor in question before you have a total freeze up on EVERYTHING , you
will not be the first to have a tractor freeze up including the transmission . SO DRAIN flush and let drip dryand install any and all filters .
 

Hmm. The B434 has a separate reservoir for hydraulics versus the more common TDH system.

When I drained the hydraulic reservoir a few weeks ago, the oil was a very dark and smelly reddish fluid. I think I had topped it up with Type F transmission fluid.

After allowing it to drain, I did the refill with an unopened container of Spirax S3 TLV, so unless it's extremely an hygroscopic fluid, I am not sure where the water would have come from. The tractor is stored in a covered shed as well.

To add further to the mystery, I decided to go out and try starting it up. In reviewing the IT manual there is a mention of putting weight on the lift arms after doing a fluid change to help purge air. The lifting was initially jerky but now is behaving sort of normally. There is a whine in the system but I was able to clear the snow as I had hoped earlier. It's now -15C with out any wind.
 
Hi, since you said -15C I assume you are in Canada and have a UK built 434 with only the one hydraulic reservoir under the seat?
Make sure the draft control lever is all the way forward when using the snow blower.
I have never seen a 434 with a breather like yours, does it have a front end loader or what other hydraulics are hooked to the tractor?
Water comes from the moist air that is in the top of the hydraulic reservoir, when the temperature drops to -15C all the moisture will be condensed out of the air and either be small snow flakes on the iron
casting or frozen into ice somewhere in the hydraulic system. In your 434 it sounds like some ice in the 3pt unloading valve and maybe the suction filter.

BTD as we used a 434 for many years to feed silage out of a bunker silo in eastern Ontario and it would get down to -35F/C sometimes and we would have to let tractor hydraulics warm up before the loader would
lift.
 

I am indeed in Canada. Eastern Ontario specifically. We got a 15cm + dump of snow that I needed to clear plus the snowbank at the road, courtesy of the snow plow.

When I refilled the reservoir, there was no space left in it for air except for the space where the seat is mounted. I know this because I filled from the back breather hole until it came out of the front fill hole.

I had used the tractor after refilling the hydraulics, to move a few things around but hadn't loaded anything on the 3PT hitch arms. I was waiting to do that because I have both a blade and a snowblower for clearing the snow and deciding which one gets mounted depends on how much snow I get. I do not have a loader.

What came barfing out of the breather hole seemed to be more like foam as opposed to the more common milk shake goo that's present when you have water contamination. Once the air escaped, the residual fluid was clear.

The Spirax is a multigrade fluid equivalent to SAE 5w30 apparently. In the IT manual, it says that if HyTran is not available, non-detergent SAE straight grade oils can be used with the viscosity dependent upon the expected operating temperature.
 
You must be closer to the St. Lawrence than me as we only received about 4", I am close to the Ottawa River.

The suggested fill level for the hydraulic reservoir on the 434 is to look down in the top filler hole and you will see a shelf, the oil level should just cover the shelf.
We used to use 20W NON-Detergent oil in the hydraulic of our 434 until we bought an IH 454 that required Hytran and then we had to switch the 434 to Hytran as well otherwise the 20W oil would get mixed in on
external hydraulic cylinders that were used by both tractors.
The foam is caused by air getting mixed with the fluid and that could be caused by an air leak on the suction line or the suction filter is partially clogged with ice. The whining of the hydraulic pump is
caused by lack of fluid flow to the pump on the suction line.
Our 434 would whine as well when it was really cold, sometimes when really cold we had to pour hot water over the loader control valves to get the loader to lift.
 

Thanks for this. I will leave the tractor be for now. Hope I don't get any more snow for the time being. When it's above freezing, maybe by the weekend, I will check the hydraulic fluid level and maybe do some exercises of the lift arms with the load in place to remove residual air from the hydraulic system.

I did not have the time to remove the suction filter and knowing how difficult it is to reinstall, may be that's best left to next spring if the system works.
 
It was somewhat warmer on the weekend and I needed to use the tractor for some work. When I started it up, it started to spew hydraulic foam from the vent again. This time the volume was less probably due to less fluid in the reservoir.

I had to change implements and again when the lift arms were unloaded, they rose up to the top position until the tractor was turned off.

After mounting the implement to the 3PT hitch, I tried each of the controls in turn. The draft control was set fully forward as suggested. What I noticed was that the speed control located on the left side of the reservoir seemed to have the most influence on how the system behaved. When set to 'fast' response, the lift arms would raise up the implement to maximum height regardless of what position I had the position control set to. When set to 'slow' the pump would complain a lot but I could then mostly get the implement to sit where I needed it to be.

I decided to take a few things apart to check for dirt or debris in the system. I found the damaged part pictured below which is described in my manual as an Orifice Assembly. I am pretty sure there are some pieces stuck inside the hydraulic control head but the hydraulic system is working much better since I have taken it out. The pump doesn't squeal and the lift arms work properly.
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