Thank you for your feedback, it’s really appreciated, and I think we all have the same problem! I’m not counting all those who don’t come to the forum to tell us what they think
So, about the 8.8 bolt, I tried it, and that’s how I discovered the problem I had!
I also stocked up (2 packs) because I know that when you clear snow from a road you’re driving on, there’s always ice coming off your car, and when you have a truck, it’s even worse (lol). So, I suspected the pins would pop out.
But I really didn’t expect the whole gearbox to break because of it.
Personally, I don’t really understand what these pins are for and why they undersized the gearbox, since with an electric motor, you can tell at any time if you’re hitting a rock or putting too much stress on the gearbox! On a combustion engine, yes, I understand! I’ve already blown pins on tractors and snowblowers because of stupid rocks, but it’s like putting a safety feature on a lawnmower when there isn’t one, I think!
So, in my opinion, this pin shouldn’t exist because the engine is much more powerful than the gearbox. They couldn’t have used the electric motor’s data as an electronic fuse, which would have prevented replacing pins due to heavy snow or other issues! It should simply indicate engine overload or something similar!
I now understand why, after launching the promotion for the professional lawnmower, they ran another promotion offering a longer warranty than ours because I think they should improve this aspect and show they’re capable of surprising us with updates so we can customize the functions ourselves, or even finally access our API requests or have local access to the machine for MQTT People with Home Assistant or similar services will love getting Yarbo, that’s for sure!
The amount of horsepower required to turn the small auger fast enough to throw the snow 40+ feet, makes the required RPMs of the impeller pretty high, the augers that draw the snow in probably have a pretty high reduction ratio. That means the motor won’t have much feedback from the augers themselves. The shear pins are designed to break at a safe torque level. The only snow blower designs I know of not using shear pins are some Honda snow blowers but those might have different motors or other different designs that allow them to not need them.
Busted my first pin today. On me. Mapped it wonky.
However what I found interesting as I was inspecting while replacing the new pin I notice this incident bent one of the tooth barbs on the auger. Slight little bent tooth now.
Yarbo Dental
This sort of thing, along with broken gearboxes, etc has me wondering about people breaking shear pins all the time. It can’t be both things. Either the shear pins are too weak and we need to buy a box of spares, or they are too strong and other things will break.
The shear pins are engineered to break at safe torque levels. Using anything stronger you’re risking breaking more important things. …Pauses to have Gemini explain it better than I am…
Measurements/specifications might not be exact, but they are accurate enough to get the point across
Purely anecdotal evidence that the shear pins don’t always shear from a particular event, but from an accumulation of smaller stresses… I went through all of last winter and most of this winter without breaking a pin, despite Yarbo going through a lot of gravel piles and leaves and other stuff.
Then last week the left side shear pins broke, and then a few days later the right side shear pins broke, without an obvious cause in either case. Unfortunately, replacing them isn’t as easy as it would seem because 1) they are so tiny 2) it is difficult to see where they need to be pointed and 3) the pin remnants always seem to get stuck in the shaft
But maybe if they are really accumulating stresses and likely to break at some point anyway, yearly replacement is a good idea even if they look “good”, so they don’t break during the job in the middle of a snow storm.
One set was the original bolts shipped with the unit, the other set broke when Yarbo lost a fight with a 2x12 before the season started, so it was a replacement set. But both sets made it through all of last season and I guess half of this one.
I had the same problem happen with my big manual snowblower a couple of years ago - Sheer pins broke due to gravel at the driveway apron. It was a major pain trying to get the remnants out because they had bent when they sheered and would no longer easily slide out of the shaft. Took a decent amount of hammering and heating things up before I could get them out.
I only had one pair on the Yarbo break but I just lined up the hole and pushed with the new pin while jiggling the auger a bit, 1 basically fell out on its own and the other needed a bit of persuasion. No percussive forces needed though😁
So, I finally received the correct (fully operational) blower module
It took a long time because the first replacement arrived quite quickly (7 days if I remember correctly). They replaced it completely, but unfortunately, it only worked for 5 minutes before the belt completely broke (I’d never seen a belt so destroyed). But it didn’t break the pins, lol While I still had my old one, I asked if I could swap the belts so I wouldn’t have to issue a warranty claim just for that. They agreed, but unfortunately, the toothed wheel was badly damaged, and they preferred that I send my old one back ;-( The steel wires wrapped around the toothed wheel and completely (sawed) it. It’s the first time I’ve ever seen anything like that (and yes, it’s always me who gets the problems that others don’t have, or rarely have, lollol). So It took 10 days for my old one to be returned, and when they received it, they sent me a new one which I unpacked and which works perfectly!!!
With all this, I can confirm the design flaw regarding the module height!! It’s like taking a Formula 1 car for city driving! You can’t clear any curbs or speed bumps!
The snowblower, as it is now, is good for asphalt surfaces but really not for dirt, rock, or other types of roads because the ice forms ruts when you drive over them, and the Yarbo is unable to get over them because it gets completely stuck, leaving you no choice but to go out in bad weather to free it But apart from this flaw, when everything is flat, it’s wonderful!!!
On the good side, this becomes less of an issue if the unit is working and can keep those tire tracks from forming.
Once they form, though… you’ll be using a garden shovel to flatten them out, lol.
Gravel and lawns aren’t much of a problem, depending on how coarse the stones are. I have good luck running a height of 0.7” on gravel with no snowpack. Once a pack layer forms, you can probably go lower - but be ready to raise the auger if the gravel starts to show.
This has been my experience as well. Basically, you need to be careful and not ingest any pebbles when they are exposed. Once covered in a good layer of snow, you should be good-to-go, even with a lower auger.
Just pay attention as Yarbo works on the gravel area(s) of your driveway, and you should soon get a feel for how low you can safely go. Don’t overdue it though!
0.5” is the lowest I go on my gravel even in the best conditions. Otherwise with the little hills and valleys and things it’s bound to scrape something. Normally I run closer to 0.75” or 1” if the base isn’t great yet.
The problem is that I have a long driveway, and unfortunately, some snow melted into slush, and when it refroze, it stayed the same! Then, when it snowed again the next day, it created dips and hollows ;-( Unfortunately, with the very low ground clearance, it really doesn’t help at that point! Yes, otherwise, after a pass with my snowplow, it helps a lot, but if I had to rely solely on the robot, I’d be outside with my shovel all the time!
