Toro HMR Interactive Steering
#1
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Toro HMR Interactive Steering
Previous Posts dealing with my successful remod of the Ogura Clutch (that runs the deck on my toro HMR 1600 Model 55620 only made for a year 1989 got me past that and now I have an issue with same mower that is irritating but not as critical. This mower has "interactive"steering, which controls the two peerless transmissions that drive one side or the other rear wheels to create a zero turn effect. With everything back together, and adjusted per the manual, I still cannot get the mower to turn right in first gear. it tries, but the minute the steering wheel is turned 45 degrees or so to the right, the mower slows to a stop. I can get it moving again (forward) by turning the steering wheel toward center. Im guessing that this has to do with the linkage, but I can assure you that I have tipped the mower up on its back and located the rods and pins exactly where they are supposed to be. If I shift to 2nd gear it will work fine, but when I am trimming I would really like to be going slower. The raritiy of this mower being a one year build may limit all your experience, but I need some ideas before I remove the deck and start again on this mower.
#2
Wish I could help but I've never worked on one that I recall. Not too many Toros around here. I don't know why it would go in second but not first. Could the belt be slipping? If not, I'd say the transmission on that side is just getting weaker than the other. Might have to adjust it a bit to compensate for that. I see that a lot on lower end zero turns... one side is usually stronger than the other after a while.
#3
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well since the transmission is all gear drive, I don't know what could get weaker. I know that belt tension is pretty critical, The belt guides are adjusted in thousanths rather than fractions, so I may have to play with that. I will have to take the deck off and raise the mower up vertical to see what happens when I turn the steering wheel to the right, Maybe I will see something there. thanks for the reply cheese, I will post back for the few owners out there of this machine.
#4
I'm trying to figure out how on earth it can use two gear drive transmissions to work as a zero turn unless it has some sort of slipping clutch that engages one side more than the other like the cone clutch system on a Dixon. But to act as a zero turn, it would have to even reverse one side. Both transmissions shift gears at the same time too? I just haven't ever seen one of these.
#5
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If you have an e-mail address I can send you a copy from the manual that shows how these transmissions are interconnected. I have never had any luck using the attach pictures to this website. The gear trans on either side does not reverse, it just slows one side or the other down enough to really turn nice and sharp. I love this mower for that reason, but the adjustments and maintenance are very critical. I can trim around a very small object with a steering wheel rather than levers,
#6
Cool... I wish there were more made to steer with a steering wheel but still have a tight radius. I have carpal tunnel and the way I have to hold the bars on most zero turns, it makes me have problems with my wrists and then it takes days for the problems to go away. I loved the old snapper ZTR with a joystick. I'll send my email, thanks!
#7
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I think I have finally determined what the problem is. Credit to my neighbor Dean, who suggested disconnecting the chain from the right side transmission to the rear wheel and see what happens. After doing that I took it out and found out that with the chain off, I had absolutely no forward motion in first gear. I had forward motion in all the other gears, and could easily turn right with full rotation of the wheel. I believe I have a stripped gear, or key in the Peerless transmission that is still engaged by a chain to the left side drive wheel. I guess I have a winter project now to see what broke, but at least I now have a smoking gun lol
#8
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This Toro 55620 has two peerless transmissions as I said before. It appears that the one with a Peerless model # 700-030 has the problem with first gear. It almost looks like there is enough room to take the top off of this transmission without taking it completely out of the machine. If I can do that, I might be able to take the whole set of gears and the shafts that they rotate on to change gears etc right out of the trans and replace what I think is the damaged spur gear PN78136 (smallest gear going into a much bigger gear) Has anyone ever done it this way? (taking a peerless trans apart while still in the tractor? ) It would sure save me a lot of time if it can work!
#9
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Well i like doing things the hard way. I took the transmission out of the tractor to get the best look at what was going on inside the case. Fortunately there were no broken gears or shafts. As best as I can tell without having it all back together, is that the adjustable rod that runs from the other transmission over to this one has never been moved,(had to heat the jam nut red hot to move it ) I am pretty sure that what was heppeng was that this trans was remaining in neutral when the other one went into first. I now have them both going into first gear when I select it with the console mounted shift lever. (you CAN take the top off the left one in the machine without removine the trans. The other one not so much!
#12
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Not quite there yet. With everything back together, the trans I had apart and re set the linkage to will not hold first gear under load. With the tractor on jackstands and the interactive steering isolated, If I shift into first gear the wheel on the left side will spin but I can put my hand on it and it will stop, therefore no improvement in my ability to turn right without stopping in first gear. Everything normal in all the other gears. I could see no visible damage to any components, but it probably could use some new gear grease. What else do I need to look for, or replace? (Peerless 700=030)
#13
It's been probably about 2 decades since I was inside of one of those. One shaft has selector keys in it. If the inside of the gear is worn where the selector keys go, it can slip. The other shaft has small splines for the gears to fit on. I don't think the splines would wear off the shaft, but they could very possibly wear out of the inside of the gear. I think your problem is going to be one of those two areas since it's only affecting 1st gear.
#14
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Hi Chuck, Not being an expert on Peerless transmissions, as best as I can tell from your description and what I have on the bench, the shaft that is driven initially by the pulley under the trans has several gears on it. I believe the smallest gear on that shaft engages the largest gear on the other shaft, which is selected by the selector keys you mention. (these two should give me 1st gear) that gear is pretty wobly right now, but I have not got it off the shaft yet to get a better look. The smaller gear seems to be ok movement wise. Will a new gear be a logical fix for this, unless I find a worn shaft when I get it apart?
#15
Yes. The largest gear on the second shaft would be the suspect area for me. The gear should be softer than the shaft I believe, so most likely the gear will be worn and the shaft will be okay but you won't know until you check. Hopefully that will be all it is.
#16
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Peerlesss Transmission
Thanks for your input, lets me know I am not ready for the funny farm (maybe) I have a friend who is a professional small engine mechanic stopping by to help me get this apart the rest of the way without breaking something. (I think he helps me so he can get his yuks for the day lol) All of the videos I have watched show bushings on the end of both shafts that just drop into the case on each side. THIS trans has actual ball bearings on the keyed shaft we are talking about. These are going to have to be pressed off, and pressed back on, so I will be learning more about Peerl.ess transmissions than I really want to know at my age, but maybe my experience will benefit someone else some day.
#17
I doubt you'll have to actually press the bearings. Maybe. They likely just slip on with a close fit. Might take some tapping to get them on and off, or worst case scenario a little puller.
#18
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Peerless Transmission
The bearings came off with a puller easily. The shaft was fine, the 35 tooth gear not so much! The Keys left deep gouge marks in each of the 3 internal legs of the gear, definitely the smoking gun (finally) Getting a new gear and some new shift keys right now! Thanks for your comments!
#20
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Everything else was bathed safely in that 140 wt grease peerless specifies and looked great. I DO have an issue with the safety switch being in there for 40 years not wanting to come out. Soaking in Blaster but it is not giving yet. I do not want to crack the alumin um case, and I do not have a pencil thin torch to heat up the switch base. What do you like to do when you have a steel switch stuck in an aluminum case?
#21
Usually I try to heat the aluminum. It heats faster and expands more than the steel, allowing the steel part to come out. Sometimes I heat the steel piece near red and let it cool down a bit and the heat transfers to the aluminum and allows removal. Depends on the scenario.
#22
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Since I really didn't want to put a torch to this case, or the switch for that matter, I thought I would try the PB Blaster one more time. THIS time I put it where it would soak the top of the case where the fat part of the switch mated to the top of the case, rather than from underneath the case top where the spring loaded ball was visible. I had faint hope until I started pulling on the breaker bar and socket attached to the switch and it started to move with the torque I was applying that I considered safe. It would not move AT ALL before I did that, so I give the Blaster credit again. That stuff is great! Saved the case, and good to go.
#23
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Since Cheese hadn't been near a Peerless 700-030 I did not want to bother him with a question I had about a wafer thin thrust washer that resides between each gear on these transmissions. The installation instructions are adamant about placing the flat side of the gear towards the shoulder on the crankshaft. Along with that they want the "chamfered" edge of the washer facing the shoulder as well. (this chamfer, or machined 45 degree angle cut into the ID of the washer allows the shift keys to ride up over the washer to engage the gear it is next to. Very hard to see, and I have found out that many people have no idea what a "chamfer" is. Peerless has a new washer made differently now, which should help one to determine which side is which for installation in their transmissions. No help for me, but I should be rocking when my Bentonite Grease gets here monday.
#24
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The bentonite made it on Saturday so I measured and placed it in the trans, then resealed the case. Put the trans back in the tractor today and it is performing flawlessly. I now know more about Peerless transmissions than I ever wanted to know, but at least they are no mystery to me any more.
#26
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Lol, no forks yet. If you still have the photo I sent you, there are two transmissions that make this mower work and both of them are 40 years old this year. The other transmissions pulley is inverted to allow for the belts to cross over each other on there way to the crazy but functional belt tightening pulleys in the back. I should service this other transmission this winter, but the allen screws that hold this onto the trans input shaft (that were both visible and easily acccessable on the broken trans are located in between the mower floorboard and the pulley, with VERY limited access. (I cant see them) I saw a utube video where the guy used a tiger saw to cut the pulley off so he could get it out. THAT is not going to happen here, but THAT challenge will wait for this winter!
#27
Huh. Can you use an extension and allen socket to get them? I assume it's the allen screws that hold the pulley tight to the shaft?
#28
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I suppose I can, after all someone installed them at the factory that way, I just hope they are not frozen after all these years. and yes there are two allen screws, one hits the half moon key in the shaft, the other hits the shaft directly from maybe 90 degrees around the shaft.