# HS520 Belt Adjustment/Replacement ???



## Golfergordy (Oct 29, 2014)

I have a Honda HS621 and the owner's manual tells you how to check the drive belt adjustment. I'm currently planning to replace the drive belt (along with the scraper and paddles) on my son's HS520, which is more than 10-yrs old, but the owner's manual doesn't tell you anything about checking or getting the belt tension correct, other than refer you to a Honda dealer.

Does anyone know how to check the belt and make an adjustment?
Thanks


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## CalgaryPT (Dec 7, 2016)

My shop manual for the HS520 for Belt Tension (Section3-11) says Clutch Spring Length s/b 78 mm (3 inches). There is some adjustment available via the Z bend fitting at the Auger Handle, but it is minor. I've replace a couple of belts before and no adjustment was ever necessary.

Let me know if you need more and I can upload the page from the manual.

HS520's are/were/remain great machines.


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## Golfergordy (Oct 29, 2014)

CalgaryPT,
Thanks very much for your information.
I've installed the new drive belt, and adjusted the clutch lever free play as per the owner's manual (7-1/2" to 8" of distance between the clutch lever and handle bar), and I then measured the clutch spring length at 3-3/8". You stated that 3" is the correct spring length, but I'm sure that the allowable clutch spring length is within a range, such as 3" to 3-1/2". Could you please check the shop manual and tell me what that range is. Also, please upload the page from the manual as you offered.


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## CalgaryPT (Dec 7, 2016)

Golfergordy said:


> CalgaryPT,
> Thanks very much for your information.
> I've installed the new drive belt, and adjusted the clutch lever free play as per the owner's manual (7-1/2" to 8" of distance between the clutch lever and handle bar), and I then measured the clutch spring length at 3-3/8". You stated that 3" is the correct spring length, but I'm sure that the allowable clutch spring length is within a range, such as 3" to 3-1/2". Could you please check the shop manual and tell me what that range is. Also, please upload the page from the manual as you offered.


The only adjustment spec I see in my manual is on these pages (other than torque specs which I can provide if needed).


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## Golfergordy (Oct 29, 2014)

CalgaryPT,
Thanks again for your assistance.
Trying all the adjustment possibilities shown on the 2-pages you provided, the closest I can get to the recommended 7 1/2" - 8" clutch lever measurement once you take out the free play in the clutch cable, and the 3" belt tension spring length, is 7-1/4" and 3-1/16" respectively. When I make adjustments to lengthen the 7-1/4" to 7-1/2", the 3-1/16" goes up to 3-1/4". To achieve a 3" dimension for the belt tension spring length, I have to reduce the clutch lever dimension to about 7", which is 1/2" below what's recommended. I would guess that the 3" belt tension spring length measurement is the more important to achieve since it's more directly related to the actual belt tension, which seems more important than the clutch lever dimension for good machine performance. For the final adjustment, I'm going with the 7-1/4" and 3-1/16" setting. 

When I first measured the clutch lever measurement with the old drive belt still installed, it was 7", but I never measured the belt tension spring length until after I installed the new belt. I'm sure there have been no adjustments made since the HS520 was brand new, so I wonder if the factory or the selling dealer set the belt tension spring length to 3" and didn't worry about the 7" clutch lever dimension being 1/2" out of spec. 

I wonder if Robert has read this thread and has anything to offer?


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## CalgaryPT (Dec 7, 2016)

Golfergordy said:


> CalgaryPT,
> I would guess that the 3" belt tension spring length measurement is the more important to achieve since it's more directly related to the actual belt tension, which seems more important than the clutch lever dimension for good machine performance. I'm sure there have been no adjustments made since the HS520 was brand new, so I wonder if the factory or the selling dealer set the belt tension spring length to 3" and didn't worry about the 7" clutch lever dimension being 1/2" out of spec.


I would have done exactly the same as you have done here. If the machine is 10 years old, expect slack in the wire rope.

The big question is, does it work OK???


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## Golfergordy (Oct 29, 2014)

Since my last post on this thread, I replaced the scraper bar and discovered something interesting in the process:

The left edge of the scraper wouldn't easily slip onto the lower edge of the auger housing when I first tried installing it. It was hitting something on the left side of the housing. I ground off enough of the plastic scraper so that it could then easily slip into the correct position, but after I tightened the mounting bolts and checked the scraper ground clearance, I noticed that only the left side of the scraper touched the ground, with the right side being approx. 1/4" above the ground. I had to loosen the bolts in the center and right side of the scraper and lower the right side only, and then I tightened the bolts back up. There was still 1/16" air gap on the right side, but I couldn't adjust the scraper any more, so that's how I left it. Then I noticed there was approx. 3/16" - 1/4" ground clearance between the new rubber paddles and ground, which is supposed to be 1/16" - 1/8". I left the machine in this condition and returned the snowblower to my son, who told me that it operated this morning (after a 3" snowfall) as well as it did when it was brand new.

I think that in the previous years that my son operated this snowblower, he must have hit something pretty hard which knocked the auger housing slightly out of alignment, which is what caused me to have to make deviations on the belt and scraper installations, that weren't quite up to Honda's specifications. Since the HS520 now works well, I don't dare try any more adjustments and consider my work to be well done. 

I have read other threads about Honda HS520's and HS621's, and the 621 owners usually agree that it's a superior machine to the 520's. I've owned a 621 for 3-yrs, and I worked on an HS521 this past Fall, and I'm starting to agree that the 521/621 series is superior to the 520's. It seems like the sheet metal of the 521/621 machines is thicker to go along with the commercial quality engine design. 

Thanks to CalgaryPT for the help provided to me.


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