OutdoorKing Repair Forum Forums Repairs and Maintenance Questions On Ride On Mowers Questions Ride On Mower Transmissions Toro Groundsmaster 72 Hydrostatic Trans problem

G'day, I was hoping some of you guys could maybe help me with some advice..
I have an old Groundsmaster 72 with the continental/ Renault engine.
I have actually just done a total rebuild of the engine and now unfortunately the machine has lost all power in drive....its still moving and I am able to cut grass, though its very slow, particularly going forward... I have noticed over time i have needed to push the peddle further in order to move...now I am flat to the floor and the machine moves very slowly....
So i guess my question is, what am i up for here? can i rebuild the transmission my self? are parts available? what is the problem?

Good morning AlwaysTinkerin.
Is there a model identification label on the machine itself (possibly located under the seat) to get specific information on your Toro Groundsmaster 72? If so, a photo of the label would help. :-)
Can you find any identification labels on the Hydrostatic Transmission to determine it's actual make and model?

HydroGear labels would look something like this: -



Peerless labels will look like this:-



Some information may be obtained from the number stamped on the Peerless (shown below), but it's better to go from the manufacturers label identification, as it's more detailed: -



If you could provide photos detailing this information, then it would be easier to find the manual relative to your specific transmisson to answer your questions.

Thank you.
Daryl.

G'day Daryl and thanks for your reply, This is an old machine, I have had a look for any ID plates or markings on the transmission/pump axle housing etc and cannot find anything...I do however have some paperwork that came with the machine showing transmission assembly and quoting the number (48-1790) I hope this is helpful?

Thank you for your response.
Just Googled the Transmission reference as "Toro Groundmaster 48-1790" and found this exploded Parts Diagram information. Hope it helps:-

http://www.ajsrepairandservice.com/pages/OemParts#%2fToro_Commercial_Equipment%2f30782%2c_Groundsmaster_322-D%2c_1985_(SN_50001-59999)%2fTRANSMISSION_ASSEMBLY_(48-1790)%2f30782-15718-1985%2f3312-444-444A0019-00017

Still not sure of the manufacturer, but if I found more information, I'll post it up for you.

Also found an exploded Parts Diagram on PartsTree.com and these transmissions seem to have been used in several Toro models around mid-late 80's: -
https://www.partstree.com/parts/tor...9999-1988/transmission-assembly-48-1790/

Sorry for the extra replies, but having a guess at the actual Toro model being somewhere near the 322-D based on the transmission information I have been reading, but they come in 2WD and 4WD versions as well. Here's a Toro link that may be more helpful if it is the wrong machine.
https://www.toro.com/en/parts?SearchText=Groundsmaster+322-D&SelectedFilterByOption=equipment

This link is also from Toro website for the transmission based on the 327, which appears to be the same as the 345 and 322-D. All of these are from around 1981-1991.
https://www.toro.com/en/parts/partdetails/?id=15710

To get an idea of year, the model serial numbers I found are:-
1984 model 40001-49999
1985 model 50001-59999
1988 model 80001-89999
Sorry, best I can do with limited information.
:-)

More research based on the Toro Groundsmaster, which is running the Renault Continental engine, indicates your mower is most likely to be the Model 327. These were built between 1985 and 1989 and Toro only lists two models, being 30781 and 30787.
Model identification and serial numbers for the machine should be stamped into a plate located in front of seat on the bulkhead.
If that is the case, then this is the Toro page you will need:-
https://www.toro.com/en/parts?SearchText=Groundsmaster+327&SelectedFilterByOption=equipment

If you are lucky, you may be able to find a secondary label on the machine as indicated in this link from JacksSmallEngines in the USA: -
http://www.jackssmallengines.com/jacks-parts-lookup/toro-model-locator.aspx

If the information above is correct, your Renault engine number should be something like R08-D15-2002.

Operators manual for the Model 327 (link below) is 52 pages and has troubleshooting information that may help. Also make sure the correct oil is used in the Hydraulic system to ensure correct operation. In this link, they indicate the Hydraulic Oil used is either 10W-30 or 10W-40, not Hydraulic Fluid as you would expect, but that is for the model I selected, which you will need to verify.

https://www.toro.com/getpub/7671

I'm still unsure of the transmission manufacturer, but it may be one built in-house by Toro. If you can confirm your machine information, then it may pay to send an email to Toro about the loss of power through the transmission and see if they will reply and post back resolution to assist others.

G'day, I believe this may be the first version of this mower, before the 322 or 327, they were the later version with the diesel engine i think. I think this model is known as the groundmaster 72, that is what is actually marked on the hood...

the paperwork i do have does have an exploded diagram of the transmission but thats it, there are no trouble shooting procedures ..
my experience with toro manuals is that they give very little technical info just very basic service details and part numbers
I have topped the transmission oil up with good quality 10-40 as specified/marked next to filler which is located between your feet..
When i took the engine out i needed to remove radiator which has a oil coolant line through it for the transmission....I am wondering if the system needs bled once this line is refitted....though i dont think this is the problem...
the model numbers for machine i have on paperwork are 30780 , 30710 , 30721
I know the machine is around 40 years old now but surely someone must be familiar with this transmission?

I have no problem pulling this thing down, I would just like to know what I am getting my self into here before i start and if indeed thats what i need to do....is it just a case of cleaning it out and replacing a few O rings? or will there be other parts that i need to replace? the whole transmission is caked in oil so its probably well due a service...

If the transmission is caked in oil, then that may indicate you have a leak in the lines somewhere, so you could benefit from a complete degrease and check for any oil leaks.
The following Toro link should take you to page 28 of their Parts and Manuals section where the Groundsman 72 is listed and starts with Model 30720 through to page 30 with Model 30780.
The following are the only Models listed as a Groundsmaster 72 with no additional name/title in these pages, so hopefully, one of them is your machine:-
Model Year of Manufacture
30725 1975
30774 1974-1977
30778 1977-1978
30780 1979-1985

https://www.toro.com/en/parts?Searc...ctedFilterByOption=equipment&page=28

I think the best way to help identify your machine would be to provide photos.

The earliest listed Groundsman 72 located above is 1973 model 30720 with serial numbers from 30001 and up called a Groundsmaster 72 Traction Unit. I've provided the link to the Owners and Service manual that has a photo of this machine on the first page. This machine also has the Continental engine R839-46 where the R should indicate it to be a Renault.

https://www.toro.com/getpub/7473

Once the machine is identified, then may be able to get the correct manual for troubleshooting.

It's a pity you can't find a Manufacturers Plate hiding on the machine with serial and model number details to make it easier, but the challenge to identify your machine is in progress.

Any bits from this one help seeing it is in Vic and will probably sell for not a lot of dollars

http://www.ebay.com.au/itm/Toro-Groundmaster-327-Ride-On-Lawnmower-/262340832324?hash=item3d14bb6c44:g:HHQAAOSw2ENW65UZ

I've just had another look and there is indeed a plate located under left leg, number is 30780-40315

thanks for that, i will keep an eye on it

Excellent work to find the Model and Serial number plate. Thank you.
Based on this, your machine is the 1984 Groundsmaster 72. Actual Model is the first set of numbers, being 30780 and the serial number 40315 shows it was made in 1984, being serial numbers 40001-49999.
I have checked the Toro website (link below), and confirmed the parts listings indicate this has the Renault R839-46-15-2005-A engine and the Transmission as being 48-1790, which you mentioned earlier.

https://www.toro.com/en/parts/partdetails/?id=15708

From this link (above), you will be able to get both the Operators Manual and Parts Manual. Both of these are 52 pages and are available to download Free from the Toro website. Link to the Operators Manual for your machine is shown below: -

https://www.toro.com/getpub/7604

Pages 32-34 of the Owners Manual deal with Traction Drive Maintenance, which your machine may only need some adjustment to fix the issue around lack of forward motion, and Pages 39-48 details Hydraulic System Maintenance, including a Troubleshooting section on Page 42 that could help determine cause.

Let us know how you get on after looking over the manuals as it may help others in the future.

Hope this information is of benefit and cures your machine.

Thanks Bushy, I went through that manual, and all i have done is adjusted rod which seems to have fixed the problem...I have only given it a short test as there is no grass to mow at the moment but it seems strong...again thanks for your help and i will let you know if the problem comes back...I think i might do a complete oil and filter change also...cheers

Thank you for your quick response AlwaysTinkerin.
Sounds like a good result and success, at the moment.
I'd give the transmission, if not the whole machine, a good degrease and clean so you can spot any leaks that may be present.
Finding the Manufacturers Identification Plate on this Toro Machine has saved you a lot of drama, especially with unnecessary replacement parts, if it was just a rod adjustment required.
It also stresses the importance of knowing the full details of a machine to get the right information. i.e. Finding any identification label to get Model and Serial numbers for research purposes. :-)
I would recommend an Oil and Filter change in the Hydraulic System sounds like a great idea judging by its age. At least you now have access to the correct manuals for the machine, as well as parts lists. They will come in handy should you need to go further into your repair if the issue is not sorted.

Note to Admin:-
I recently suggested, in the past few days, of having a separate section for Transmission issues. As this query is located way down the Forum List in the "Customising and Modifying Ride-on Mowers" area, is there a better section this can be moved to so it is more available for others seeking information on their Transmission Issues?
Thank you.
Untrained, but computer savvy in tracking down information.
Daryl

Tinkerin, not sure if you followed the one on ebay, sold for $513, just proves I have no idea what some people will pay for things, I'm always gobsmacked, I can't work these ride on mowers out

Good evening NormK,
It maybe a simple case of getting hold of a cheap replacement deck or for other parts. Then again, maybe it was an ODK Member who read this Post and scored a great buy. :-)
Funny it was being sold in Vic when it used to be a Sydney Water Board machine (going on name shown in their photo on the machine).
Maybe they should have joined the ODK Forum and got the decks hydraulics working and then sold it in full working order for a heap more.
Makes me wonder if they did a repair/replacement on a blown hose (or whatever) and used Hydraulic Oil instead of the correct fluid for the system, being motor oil 10W-40 (or 10W-30) for the Model 30781 as I discovered, which is why I have suggested a separate section for the ODK Forum to be created on Transmissions/Transaxles.
Maybe I should suggest it to be a General Section on Hydraulic Systems to cover Transmissions, Transaxles and Hydraulics instead.
Have a happy Easter all, and Cheers
Daryl

Hi Daryl, of course you are right, if somebody had one of these and was chasing a particular part to get theirs going again, $500 doesn't go far and seeing there is over 9000 members listed here there is always a chance that some lurker saw that I had put it up here and if that is the case I possibly did the seller a favor, or am I overthinking this.

Anything's possible NormK, so how do we get our commission? :-)