Snowblower gearbox oil

[babzog]

Last year, I picked up a well-used McKee 6' snowblower. It works well enough, even though it's seen some abuse in its days. Looks like there's fill and drain holes on the site of the gearbox (not in very convenient positions, I might add), so would I just add oil till it flows out the fill hole or should I add a smaller, prescribed amount instead? How often should I change the oil in the gearbox and what kind of oil should I use?

Thanks!

 

[DemcoEd]

if I didn't know when the last time the oil was changed, I would drain it out and replace with new 80/90 gear oil. Small price to pay for a piece of mind.

 

[babzog]

Sounds reasonable (though I'd prefer a piece of something else... ). So, should I fill to the top of the fill hole, or put in less? And how often (either running house or calendar time) should it be changed?

 

[Fixemall]

Should be a third hole for sight level, about 1/2 to 3/4 up the side of the gearbox. Put a strong magnet on the drain plug and run the unit for about ten minutes, shut it down and drain it, inspect and wipe drain plug for filings, reinstall plug and fill till fluid runs out the sight plug on level surface. Should be good to go. Make sure you use the right gear oil, some take 75 weight not 90.

 

[babzog]

This is the gearbox in question. I thought there were two ports, but it appears there's just one upturned and capped. So, what do I do with this thing? I see no drain plug on the bottom either.

How would I know which gear oil to use - 75 or 90? There appears to be no info placard on this thing.

 

[JCByrd24]

That doesn't look like a factory configuration to me. I'd remove the elbow to drain, pull the plug out of the elbow and put it in the hole left by the elbow (after draining). The fill is the bolt head looking thing a couple inches above the elbow, looks like a vent fitting to me. Yes, fill up until no more goes in the fill hole.

 

[mark1]

That's easy..drain it anyway you can then fill it using the upturned fill plug till the oil is up into the elbow. Either weight will be good.

 

[babzog]

If I just drain it to the bottom of the hole where the elbow is, I'll still have an inch or so of oil in the gearbox. I suppose I'll have to suck it out somehow. As for filling... is it to the hole above the elbow or just to the elbow?

 

[Fixemall]

Get an empty pail and a length of plastic tubing and vac that thing out using a compressor blow gun. It is very easy and fast, just cut a slit in the pail end of the tubing about 6" from the end just big enough to get the tip of the blow gun in there, insert the other end in the gear box and blow compressed air toward the pail, the air will create suction and get all the sediment from below the drain port. I use a similar setup to degunk stuff that won't drain by gravity all the time, nice thing is when it gets too dirty you just get another section of tubing and go...you would be surprised what is lurking at the bottom of some assemblies.
Based on age of that thing I would go with synthetic or Dino 90wt.

 

[babzog]

I ended up just setting the blower down on an angle and pulling the cover. Glad I did... all I found inside was a tiny bit of milky water with maybe a drop of oil mixed in. :shocked:

The old gasket was cracked, probably letting all the old oil out while under the previous owner's "care". Hosed it out with brake cleaner, wiped it out real good, cleaned up the cover, then used Permatex to create a new gasket. Took almost a whole bottle of gear oil to fill 'er back up.

Thankfully, the innards were still clean and rust-free and seemingly undamaged.

Amazing the neglect that some people inflict upon their equipment. Thanks for the input everyone!