Max IV, T20 or clutch issue?

[rickemd1]

So after months of overhauling my max, today was the day to fire it up and take a ride. After about 5 minutes of cruising around my property and getting almost back to my garage the machine would no longer turn either direction. It would creep forward but no left/right steering. So much for the maiden voyage.

I'm sure someone has an idea where I need to start troubleshooting. Anyone Bueller.

[amphibious drew]

Check to see if the clutches are engaging in nuetral. The. Go from there. A wet belt could even cause what you describe.

[rickemd1]

@@ amphibious drew, thanks for the guidance.

So I understand that there are no dumb questions on this forum so I'm going to ask.....How do I tell if the clutches are engaging in neutral?

I do know while looking at it that the engine clutch or whatever that part is called, it was drawing in engaging the belt as the RPM's increased which seems to make sense to me. It was starting to rain, a light rain during the 5 minute ride, its possible that the belt got wet. I didn't smell anything burning like rubber or ATF.

Could also be that I have too much slack in the drive belt. It's the stock cog belt for the Max iv that I bought from RR. I removed all the engine shims previously installed with the old thin belt and have the engine mounted on the engine platform.

For my own edification what are the symptoms of a failing T20?

[amphibious drew]

Just make sure the belt is going up and down on the clutches. It starts at the bottom of the drive and rises to the top, and does the opposite on the driven. It could be a too loose, but width is more important. 5 minutes of rain shouldn't make a huge difference, and you would have probably heard a sqeal. It is possible for the bands to delaminate. This happens sometimes when different fluids are used in the transmision and the glue dissolves that holds the friction material on. That could explain your symptoms, and could only be verified by splitting the t20 back open. Did the engine rev fine the entire time, or was it lacking power as well. The throttle cable can slide if it's not tight enough causing limited revs. I hope it's something cheap and simple like that for you.

[rickemd1]

Yep Drew the belt was going up and down on the clutches, seemingly opposite of one another. There wasn't any squealing from the belt or the clutches while all this was going on. The engine revved up and down just fine while this was happening. I was able to drive it straight ahead only, no turning even though I could see the belt moving up and down on the clutches. When I pulled the left lever back while in forward, the left side wheels stopped and only momentum caused a slight turn to the left.

I went through every piece of this machine prior to reassembly except the T20. I have said it over and over again that it was the one uncertainty of the whole build. Did I mention that I never drove the Max or saw it operate and basically bought it sight on seen.

Prior to reassembly I dumped about a gallon of grey fluid from the T20. After emptying I poured a quart in and rinsed and rolled and dumped x4 before adding the ATF and diff fluid. After the last rinse the fluid was coming out red. Could be that the previous owner destroyed the T20 with too much fluid?? There weren't any ATF leaks on the T20 or in the belly during disassembly nor any saturated areas around the output shafts.

I guess I'll see if I can find a thread on here about the belt tension/adjustment and see if I'm close with my belt, hopefully that's the issue but it doesn't explain why it would run fine then suddenly not turn at all. The belt is supposed to be the stock belt and if I had to guess I would say it's a little more than 1" wide.

[Rusty-Gunn]

A bit of rain won't cause the belt to slip. I was in constant rain for about five hours a few days ago. No issues but a few squeeks, which is normal.
I did get "tons" of water sloshed over the Max IV July 4. Gallons if water spilled over our laps and into the left (belt side) engine vent screen and on the belt... no power, just belt slipage. We did move mere inches at a time and got out. Tide was high, winds were high, waves were high. The good Lord was with us that ride!
Once the water was drained out the machine ran fine.

[amphibious drew]

What you described sounds like gear oil was in your t20. Then you switched to ATF like a proper aatv owner. The problem is going to be your bands delaminated. I almost guarantee it. On the plus side, you caught it fast by asking the right questions on here. Your going to need case half gaskets and O-rings for the plungers, but your case needs split open and the bands sent out for relining. Don't try and drive it anymore for you are at risk of scouring your drums if you do.

[ARGOJIM]

I would check you belt tension first, it should be 1-1/2 inches measured pushing on one side of belt only. If that seems good you have other issues. How much travel do your sticks have and did you adjust the bands or just start off with where they were?

[msafi65]

Your driven clutch may be turning on the input shaft if the key sheared. Everything still turns but no power to the transmission. The factory belt is 1 3/16" wide and should sit nearly level with the outer edge of the driven clutch. If you have a Briggs engine they had 2 1/8" thick washers between the mount and the engine from the factory. The washers we're there to set the belt tension. I would tear down the t20 as it sounds like it may have had water in it. To see if the input key is missing put trany in forward and rotate the driven clutch. If the clutch is turning on the shaft the clutch will rotate and the two washers behind the clutch will not be turning. Hope you find the problem.

[rickemd1]

Good Ideas

Lots of great points from everyone for sure.

I need to see if the washers on the driven are moving or not. Need to check the belt tension after reinstalling the factory installed washers. And I'm pretty sure the belt that I have is the correct belt based on the dimensions provided.

I'm out of town for the next few days but as soon as I get back I'll check out all these recommendations and suggestions and get back to ya'll.

I'm just hoping this isn't as catastrophic as it sounds like it might be, forever the optimist.

Thanks again for all the guidance folks, much appreciated.

[rickemd1]

ARGOJIM,

Ok so I got back home yesterday and shimmed the engine up to try an obtain the 1 1/2 inches of defelction on the belt, 3 large washers. I might have a little more than the inch and a half deflection at this point but I don't think that it matters now because I did try to drive it around my yard once and it seemed to perform as it should, turning left/right in both forward and reverse. Then again as I was trying to steer back to my garage, no steering in forward. I was able to drive it into my garage with some effort in reverse. It's almost as if the gearbox gets hot and starts slipping. IDK. Guess I need to split the case at this point.

[amphibious drew]

Wait a minute before you split it open. Do a band adjustment first and see if that works. You may just not be gripping enough on the drums to turn on pavement. Even a properly adjusted t-20 should not be turned from a dead stop on pavement. You should be driving forward or reverse a little bit. You may want to change your ATF as well and don't put any friction additive in it at first to see how she does.

[hydromike]

I don't think this has been brought up yet, but how hard are you pushing forward on the laterals when you're trying to steer it? I'm assuming you still have the spring-loaded laterals. Maybe there's enough spring and enough "grab" to the bands when it's cool to steer more easily. I'd do a band adjustment like Drew says and make sure you're pushing hard and pulling hard on the laterals to steer.

[ARGOJIM]

Both good points by Drew and Mike along with the woodruff key from msafi65 which is easily eliminated by pulling the clutch, if the spring has sprung it will also have less power and progress worse, if the bands are out of adjustment no matter how hard you push the c channels can only travel so far.

Did the machine operate properly before tear down? Let's start with a year or serial number, engine in it, driven clutch spring color , belt number you're running and what you have done so far, that should get us all up to speed.

It is possible it will have to come apart and may need some parts, or maybe it's something you or we are just not thinking. Didn't see any pics in the gallery so some of that in the trans area may also help.

Most of these other guys are more familiar with the t-20 than me, yet I do like to k.i.s.s. the little stuff before just ripping stuff apart.

[rickemd1]

Ok guys thanks for all the suggestions and advice. Rebuilding one of these without manuals has been a lot of fun

Here's some specifics about the machine; The serial number is 10375 and I think this makes it a '95 or '96. The engine is a Vanguard 16 HP I think from the numbers (303447). The driven clutch as you can see from the pictures is rust colored and when it rotates the 2 washers inside of it rotate with it as suggested by msafi65. The belt that I got from Richard is a MAX1092M2 and is 1 1/8" wide. I have had the frame and assorted control tubes etc blasted and powder coated. New Peer #50 and Tsubaki 530 chains, new drive sprockets and bearings all around.

I bought it sitting in a backyard full of water and not running. Of course all the chains were toast, drive sprockets were shark finned, T20 to rear axle chain on the left side was broken, all bearings FUBAR'd, and everything was rusted. I got the engine to run with fuel dumped in the carb but there was no reason to try and get it driving with the worn sprockets so I never drove this machine or any other like it before last Tuesday when I first posted my thread.

Prior to installing the T20 which is the only component that I didn't go through thoroughly, I drained about a gallon of gray goo from the gearbox. I flushed and filled and flushed and filled until pure red fluid came out, or about a gallon of ATF later. I added the ATF along with the diff treatment in the top vented hole until fluid came out of the bottom hole in the installed position. I also broke one of the diamond shifters in the process and replaced both of them with new shifters.

The sticks both have 4" inches of travel from the forward position (springs are installed). I have made no adjustments to the bands. The bottom plungers seem to be adjusted equally and the top plungers are about 1/8th of an inch off from one another. I didn't notice any difference regarding the level of effort to make the machine turn in one direction over another.

Since the original post I have adjusted the engine height with washers (yesterday) to acheive the 1 1/2 belt deflection on one side. I drove it yesterday and at about the 5 minute mark once again the steering started to fade. I was able to drive around on my grass and do some donuts beforehand, go forward and backward, right up until it quit steering or moving forward. I limped it back into my garage in reverse. I DID NOT try pushing the sticks forward or at least I don't recall doing that at anytime while driving forward.

Why does it steer fine for 5 minutes then suddenly fade? I'd bet that if I went outside now I could duplicate the ride I had yesterday and last Tuesday......for 5 minutes anyway.

Here are some assembly pictures.......T20.jpgframe and controls.jpgframe and controls front.jpgBody installed.jpg

And if anyone thinks that I need to adjust the T20 could you advise a tool other than the one Richard sells or MuddOx sells? I read where Mike said you didn't need to use tool to get the 5/16ths movement top and bottom. And I've looked at the PDF section of the T20 where it describes adjustment.