# HSS928 SST oil expansion kit



## Toon (May 11, 2021)

Hi Folks
I have read here on this site that there is an external oil expansion kit that was installed on the early HSS928 models. Does any one have a part number and perhaps pictures of the way this kit was installed. I think I would like to upgrade my 2016 machine.
Thanks


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## tabora (Mar 1, 2017)

Here is the thread with the discussion... Check your serial number against the range in the first post. Later HSS units don't need the tank because the SST has internal baffles that perform the same function.








Honda HSS Service Bulletin: Intermittent Ground Speed...


Cavitation can cause air to sometimes enter the HST pressure circuit under the described conditions. This is rare, but can happen. What's the fix? For customer units, an expansion tank is fitted that will prevent air from getting into the circuit. Units built after the affected range are...




www.snowblowerforum.com





Pictures:


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## tabora (Mar 1, 2017)

The parts are the ones in the upper-left corner #8 - #15...











Ref NoPart NumberDescriptionSerial FromSerial ToQty00815422-V45-PA0TUBE, OIL10000019999999 1
 

00956850-V45-PA1TANK, OIL10000019999999 1
 

01056853-V45-PA0COLLAR, TANK10000019999999 2
 

01156860-V45-PA1ELBOW ASSY., OIL10000019999999 1
 

01290303-V10-000NUT, NYLON LOCK (6MM)10000019999999 2
 

01394201-30180PIN, SPLIT (3.0X18)10000019999999 1
 

01495002-40850-08CLAMP, TUBE (D8.5)10000019999999 2
 

01595701-06016-07BOLT, FLANGE (6X16)10000019999999 2


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## Toon (May 11, 2021)

tabora said:


> The parts are the ones in the upper-left corner #8 - #15...
> 
> 
> 
> ...


Thank you. I will see if I can get these ordered Monday. Can this be done with the transmission in place?


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## tabora (Mar 1, 2017)

Toon said:


> Can this be done with the transmission in place?


So your machine falls into the affected range? I've not experienced the procedure since mine was installed by a dealer under the Service Bulletin, but it sure looks like it can be done with the snowblower level.


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## Toon (May 11, 2021)

tabora said:


> So your machine falls into the affected range? I've not experienced the procedure since mine was installed by a dealer under the Service Bulletin, but it sure looks like it can be done with the snowblower level.


Yes mine falls into the affected range as my serial number is 1004551 and the affected machines fall between 1000001 and 1018373 for a HSS928A.
That's what I get for not registering my machine when it was new. Having had 20 years of great service out of my HS828 I got complacent.
I'll order the parts and have a go at the upgrade and will let you know how it goes.
Thanks for your help with the part numbers and pictures. This site is great, I wish I had found it sooner.


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## Toon (May 11, 2021)

Just ordered the parts. $122.69 US.


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## Toon (May 11, 2021)

tabora said:


> Here is the thread with the discussion... Check your serial number against the range in the first post. Later HSS units don't need the tank because the SST has internal baffles that perform the same function.
> 
> 
> 
> ...


Hi Tabora
Just looking these pictures over and noticed the oil level in the expansion tank is lower than the oil level needs to be in the transmission. Am I correct in assuming the transmission is completely full of oil and syphoning action keeps it that way as the oil expands and contracts, with heat, from use?


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## tabora (Mar 1, 2017)

Toon said:


> Just looking these pictures over and noticed the oil level in the expansion tank is lower than the oil level needs to be in the transmission. Am I correct in assuming the transmission is completely full of oil and syphoning action keeps it that way as the oil expands and contracts, with heat, from use?


Presumably? The SST oil level is maybe a bit higher than the height of the oil in the tank? Or perhaps when the tank is used the transmission is filled all the way? A good question for Honda...


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## Toon (May 11, 2021)

tabora said:


> Presumably? The SST oil level is maybe a bit higher than the height of the oil in the tank? Or perhaps when the tank is used the transmission is filled all the way? A good question for Honda...
> View attachment 185006



Honda USA sent me on to Honda Canada, and Honda Canada sent this reply.

Thank you for contacting Honda Canada Customer Relations department. 

Please note, that we are not trained technicians, and we cannot speculate on how to set up the expansion tank for Hydrostatic transmission on your 2016 Honda Snow blower. It is for that reason we have our dealerships in place, we assure you that the service manager and his technicians will do their best to ensure the proper functionality of your vehicle, and explain how components operate as per Honda standards. Please feel free to visit the following link, where you will have the option to locate the closest authorized Honda Dealer by entering your postal code, or city of residence:
http://powerequipment.honda.ca/dealerlocator 
It just makes me think a little less of Honda.


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## tabora (Mar 1, 2017)

Toon said:


> It just makes me think a little less of Honda.


Honda Canada support has failed to impress me on a number of occasions... However, the sales/marketing folks who specify the options for the Canada market seem to be on top of things... The HSS928ACTD having the same features as the HSS1332ACTD and the HS720CC having the GS190 engine are a couple of examples.


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## Toon (May 11, 2021)

Well the parts arrived on Thursday and I got around to installing them today. I installed the expansion tank on the back of the blower frame to get more height so the oil would gravity feed into the SST transaxle.


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## orangputeh (Nov 24, 2016)

Toon said:


> Well the parts arrived on Thursday and I got around to installing them today. I installed the expansion tank on the back of the blower frame to get more height so the oil would gravity feed into the SST transaxle.
> View attachment 187419


Interesting to learn down the line how this works for you.


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## Toon (May 11, 2021)

orangputeh said:


> Interesting to learn down the line how this works for you.


I blew the snow yesterday and I expected the oil level in the expansion tank to go down as there should be air in the top of this SST transaxle, but it did not go down. I used the original vent fitting on the top of the transaxle as it is very difficult to access.
Does anyone know if the original SST vent fitting has a check valve in it, that would prevent the oil flowing into the transaxle?


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## maxcbrdriver (Apr 13, 2020)

My HSS724 service manual doesn't say whether there is a check valve, but I suspect not. The manual does make note to rotate the breather output 120 degrees clockwise when looking at the transmission from the back, top down.


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## Toon (May 11, 2021)

maxcbrdriver said:


> My HSS724 service manual doesn't say whether there is a check valve, but I suspect not. The manual does make note to rotate the breather output 120 degrees clockwise when looking at the transmission from the back, top down.


Thanks I didn’t think there would be as air has to travel in both directions for a vent to work. But you can never be sure.


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## wgmccorm (2 mo ago)

Toon said:


> Well the parts arrived on Thursday and I got around to installing them today. I installed the expansion tank on the back of the blower frame to get more height so the oil would gravity feed into the SST transaxle.
> View attachment 187419


 Having a similar problem and want to do this fix myself. Did the parts come with installation instructions?


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## tabora (Mar 1, 2017)

wgmccorm said:


> Did the parts come with installation instructions?


Toon kinda made a departure, though. He didn't mount the tank where it was meant to go. His is higher up; still waiting to see how it works out for him.


wgmccorm said:


> Having a similar problem


Does your serial number fall within the affected range? If not, you may have something else going on...








Honda HSS Service Bulletin: Intermittent Ground Speed...


Cavitation can cause air to sometimes enter the HST pressure circuit under the described conditions. This is rare, but can happen. What's the fix? For customer units, an expansion tank is fitted that will prevent air from getting into the circuit. Units built after the affected range are...




www.snowblowerforum.com


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## wgmccorm (2 mo ago)

tabora said:


> Does your serial number fall within the affected range? If not, you may have something else going on...


HSS928AAT Yes, it is in the s/n range, bought the machine in November 2015. I think it's been experiencing this issue for the last few years, but it was _very_ noticeable at the end of last season. No trailer or truck, so I'm willing to try this solution ($123) at home. My other thought is that it might be a worn drive belt ($51), so I'll look at that first before ordering any other parts.

Very slow in forward gear. The engine is running strong, starts on the first pull every time, blows snow as good as ever, the engine oil is clean, fresh gas, new spark plug, and adjusted shift lever cable. Any other thoughts?


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## tabora (Mar 1, 2017)

wgmccorm said:


> Very slow in forward gear. The engine is running strong, starts on the first pull every time, blows snow as good as ever, the engine oil is clean, fresh gas, new spark plug, and adjusted shift lever cable. Any other thoughts?


No, that sounds like the hydro oil aeration issue. Too bad you can't get to the Honda dealer. They should still cover it as a known issue under the Service Bulletin. It's a design fault, not a warranty issue.


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## Toon (May 11, 2021)

wgmccorm said:


> Having a similar problem and want to do this fix myself. Did the parts come with installation instructions?


No the parts came without instructions. 
I used it from January 2022 till spring and still did not see the oil level drop in the new expansion tank I had expected. 
On the bright side I have not experienced the intermittent slippage I got when the machine was shifted forward to reverse many times in short order which was the only occurrence I had causing slippage of the drive system. 
If I ever have the transaxle out, I will certainly inspect the fitting on the top and look for a check valve.


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## Superman58 (Feb 7, 2019)

Had mine done under warranty, The expansion tank. I can’t really tell if it moves forward any faster f or reverse. I forget the rule of thumb so many feet distance in so many seconds.
PS this was done back in 2017. A picture of the reservoir I marked it with magic marker when the oils Cold it’s below the Mark.


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