I’ve had growing problems the last couple years with one of the control cables on my Sears snowblower. One of those cables like a bicycle brake cable, with the inextensible inner wire, and the incompressible outer sheath. I’m sure there’s a technical name for cables like that, but I don’t know what it is. (Update: They’re called Bowden cables.)
It’s the cable that directs the discharge chute up or down. It became very sticky, so that I could pull the lever to lower the chute, but when I pushed the lever to raise the chute, it wouldn’t go back up by itself.
In previous years, I had tried to lubricate the cable with some 3-in-1 oil, but the effect didn’t last.
This year, I did some research and found a couple approaches that people have used to lubricate cables for other machines:
- You can buy a cable lubrication kit at motorcycle shops. It comes with a pressurized can of lubricant, and a little adapter that fits over the end of the cable sheath. Apparently you don’t have to remove the cable from the sheath, the adapter seals around it somehow. Just install the adapter, connect the pressurized can, and spray the lubricant through the cable.
- I also found a mention somewhere of a clever trick from the snow-mobile world: lubricate your cables with automatic transmission fluid. Unlike 3-in-1 oil, it doesn’t thicken up at low temperatures. And it’s got a lot of detergents and cleaners in it to keep the cable clean.
I happened to have a mostly-unused quart bottle of transmission fluid, so I thought I’d give it a try.
I removed the cable from the snow-blower and brought it into the house. Before adding the ATF, I wanted to try to clean out the cable as well as I could. I used WD-40 for that. I hung the cable up from a ceiling joist. I squirted WD-40 into the top end and worked the cable for a few seconds. And repeat. Many, many times I repeated. Eventually, black gunk started coming out the bottom end of the cable. I continued repeating small injections of WD-40 for what seemed like an eternity, but eventually, the gunk coming out the bottom of the cable started to run clear.
At that point, I started injecting ATF in the top. I used a syringe, because the gap between the cable and the sheath is so small. When the gunk coming out the bottom had the same clear red colour as the ATF going in the top, I figured the cable was finally well cleaned and full of ATF.
I put the cable back onto the snow-blower, and I’m happy to say it’s been working great since then, through a few pretty heavy snow-falls. In fact, I had to tighten up the friction on the control lever, because the chute was tending to creep up all by itself. It’s fabulous now.