Cold weather slow FEL

[valley]

My FEL was working great. I drained the hydraulic fluid and refilled with the same type and weight fluid 32. Now,with the return of cold weather, it takes a long time for the FEL to start moving.
Wondering if I should flush the system again and refill or fill with lighter oil or both.

 

[Diamondpilot]

I would check the filter first. You may have stirred up the pot and now its partially blocked.

Chris

 

[greg_g]

Hindsight is 20/20, but a flush should probably been included before refilling with fresh. And I NEVER change fluids without also replacing the associated filter or cleaning the associated screen. Also - are you sure you bought AW/ISO32 hydraulic fluid? Some folks have mistakenly used AW/ISO32 machine oil. It foams, effectively infusing air into the system.

//greg//

 

[Diamondpilot]

Hindsight is 20/20, but a flush should probably been included before refilling with fresh. And I NEVER change fluids without also replacing the associated filter or cleaning the associated screen. Also - are you sure you bought AW/ISO32 hydraulic fluid? Some folks have mistakenly used AW/ISO32 machine oil. It foams, effectively infusing air into the system.

//greg//

Good point about the oil. I would go back and check.

Chris

 

[RonMar]

Did you mess with any of the fittings? Is anything loose? If something on the suction line is a little loose, it could be sucking air in thru a pinhole leak instead of lifting the cold fluid up and out of the resovoir...

 

[valley]

Thanks Guys, I didn't change anything just changed the oil. It worked well after I changed the fluid until the temp dropped. Its not real cold its 30*. Maybe I'll flush the system and check the screen tomorrow. What weight oil do you use in the cold? I have 32 in now. Thanks for the input.

 

[greg_g]

T What weight oil do you use in the cold? I have 32 in now.

I use AW/ISO32 year round; thin enough to work right away with weather in the teens. A little slower warming up in single digits. AW32 has a viscosity equivalency of 10W engine oil. Might find some thinner in your area, but what's sold around here starts at AW32 and gets thicker.

//greg//

 

[valley]

greg, I bought and used hydraulic oil and it is 32. Crossed my mind too if I could have put some gear oil in there. When you flush your system did you break all the fittings or just drain at the reservoir?
We have a storm going that they say will be out of here by noon.

 

[RonMar]

A simple changeout, depending on what cylinders were in what positions, would still leave perhaps a gallon of the old oil in the cylinders and lines on your typical small loader. Perhaps there is still enough old oil in the system to be effecting your cold weather performance. A flush then changeout also results in this same leftover, but it is of mostly the flush fluid(kerosene) that will evaporate out of the system over time thru use, to be replaced by regular hydraulic fluid.

I recall reading about one guy who propped up his loader and disconnected all the cylinder from the loader structure and layed them out so they could fully extend and retract without touching anything. Then he applied compressed air to the system and worked the controls repeatedly to work most all the old oil out of the system...

 

[greg_g]

When you flush your system did you break all the fittings or just drain at the reservoir?

My tractors are a bit different than yours; each has two pumps, two completely independent hydraulic loops. But in general practice, just drain at the sump. Doing so - especially the first time - usually requires a drain/flush/drain/flush repetition.

When the old fluid's been replaced by kerosene, start the tractor and exercise all the hydraulics. Get that kero pumping through the system, drive around a few figure 8s, hit some bumps, make the kero splash into corners and crevices. Stop, drain kero through cheesecloth or window screen. That way you get rid of the big chunks and globs, and be able to re-use the kero for additional flushing. Repeat as necessary, until no more chunks and/or crud are caught by the cheesecloth or screen. Refill with fresh hydraulic fluid. Repeat the figure 8s, topping up the fluid if necessary. Park the tractor with the front a bit higher than the rear. Now's the time you want to service the suction screen or replace the filter - depending upon how you're configured.

The next day, what kero is left in the sump will have settled to the bottom. Drain till hydraulic fluid comes out. Top up again. May be the last time you ever have to do it. I flushed both of my current tractors as soon as I got them. 700 combined hours later, the hydraulid fluid is nearly as clean as the day it was put in.

//greg//