Snowblower Adjustment

[RodNH]

I have a new Bobcat SB200 72" snowblower. There is a separate steel plate that partially blocks the upper left quadrant of the fan opening. The bolts that hold this plate in place are in slotted holes in that plate. These slotted holes permit between 1/2 and 3/4 of an inch horizontal adjustment of this plate. The as-delivered position of this plate is as far to the left as the adjustment permits, yielding the maximum opening to the fan. The promotional literature for this blower indicates the following:
"The fan opening is adustable, allowing the operator to control the amount of air and snow entering the efficient 6-inch deep fan."
There is no mention of such an adjustment in the Bobcat O&M manual for the blower. The dealer has no idea what such an adjustment is all about. My request to have the factory rep address this adjustment resulted in the dealer's expressed opinion that the factory rep was not particularly suited for such matters!
Does anyone here have a handle on this adjustment? When would I want to change it? How is the performance modified by doing so?
Thanks,
Rod

 

[bludorbronc]

the opening could have a venturi effect on the amount of suction the fan is sucking, wider opening the slower, smaller opening the faster it sucks snow. if it is only 3/4 inch difference and not to hard to do ,i would adjust it all the other direction and stand back and see if you can tell the diff. you mite want to test on varying types of snow conditions, lite, heavy,dry or wet.

 

[bludorbronc]

the opening could have a venturi effect on the amount of suction the fan is sucking, wider opening the slower, smaller opening the faster it sucks snow. if it is only 3/4 inch difference and not to hard to do ,i would adjust it all the other direction and stand back and see if you can tell the diff. you mite want to test on varying types of snow conditions, lite, heavy,dry or wet.

i fergot to tell you that i deal with some great people that are bobcat dealers in pennsylvania, they should know about snow,mailto:[mailto:[email protected]]if anybody can help they will.hope it helps, russ

 

[skidsteer.ca]

i fergot to tell you that i deal with some great people that are bobcat dealers in pennsylvania, they should know about snow,mailto:[mailto:[email protected]]if anybody can help they will.hope it helps, russ

I doubt you will see any real diffeence.The Erskine ones bolt on too but are not adjustable. They have been making blowers for 50 years, including 17 years for Bobcat. The purpose of the plate is to help keep the snow on the fan as it is lifted.
Ken

 

[RodNH]

I doubt you will see any real diffeence.The Erskine ones bolt on too but are not adjustable. They have been making blowers for 50 years, including 17 years for Bobcat. The purpose of the plate is to help keep the snow on the fan as it is lifted.
Ken

Thanks for the replies. I have also asked Bobcat through their website about that plate. Here is their response:
"Thank you for your interest in Bobcat equipment.
In regards to your question, the slotted plate should be at its maximum opening for operation the majority of the time. When blowing in very heavy and wet snow, the cover may be slid to the right (closed) to limit the amount of snow entering the fan. This allows the fan the opportunity to eliminate the wet/heavy snow more easily.
If you have further questions, please do not hesitate to contact us!
Thank you for contacting Bobcat Company."
I don't know if that is just a bunch of BS or not. It seems odd that if such an adjustment is worthwhile bothering with, Erskine would also have it. The small amount of adjustment permitted by the slotted holes wouldn't seem to make much of a difference. However, when I get some wet snow to deal with I'll give it a try and see if I can notice any effect.

 

[skidsteer.ca]

Thanks for the replies. I have also asked Bobcat through their website about that plate. Here is their response:
"Thank you for your interest in Bobcat equipment.
In regards to your question, the slotted plate should be at its maximum opening for operation the majority of the time. When blowing in very heavy and wet snow, the cover may be slid to the right (closed) to limit the amount of snow entering the fan. This allows the fan the opportunity to eliminate the wet/heavy snow more easily.
If you have further questions, please do not hesitate to contact us!
Thank you for contacting Bobcat Company."
I don't know if that is just a bunch of BS or not. It seems odd that if such an adjustment is worthwhile bothering with, Erskine would also have it. The small amount of adjustment permitted by the slotted holes wouldn't seem to make much of a difference. However, when I get some wet snow to deal with I'll give it a try and see if I can notice any effect.

I suppose, if the plate slow the speed the snow could enter the fan it would help keep the fan rpm up, which of course is harder to do when the snow is wet/heavy. But what percentage of the diameter would that plate change the opening?
Let us know if you see any difference.
Ken

 

[RodNH]

I suppose, if the plate slow the speed the snow could enter the fan it would help keep the fan rpm up, which of course is harder to do when the snow is wet/heavy. But what percentage of the diameter would that plate change the opening?
Let us know if you see any difference.
Ken

By my calculations, moving the plate as far to the right (looking at it) as possible (about 5/8") will result in approximately a 4% reduction in normal free area to the fan. That's not a lot and I seriously doubt one would be able to see a noticeable difference in performance without a direct side-to-side comparison under constant snow and travel conditions (not reasonably practical) or some very specific measurement(s), also under constant snow and travel conditions. I really don't expect a "wow, there's a difference" result but I'll try it sometime when conditions allow.