[qbgLOVs7q]

Hello,

I have a AC410S that is having issues being able to climb up my hills.

At the outset, it can do it fine. But some time later (30 minutes or so on a warmish day), it won't. I have to move into 1st gear.

The tires are not slipping, and I'm not hearing/feeling anything "abnormal" from the tractor. If I move the "control lever" to the Reverse position (with clutch engaged) and then back to the Forward position, I feel a bit of grab, but it fades very quickly.

In perusing the forums, I did see someone in another thread mention a similar issue, stating: "The only tractor I had that didn't climb that hill was an old Dynamark with a worn out hydrostat,after it got hot (half hour or so) you couldn't even get it to move on FLAT ground!...."

So, I presume the "hydrostat" the poster mentioned is the "hydrostatic transmission." My Shuttle does not have that. So I'm presuming my issue is related to drive belt tension.

Would some kind soul be willing to help direct me...presuming I'm even on the correct path?

I note that I do have in front of me the "Operator's Manual," and am looking at Figures 24, 25, and 26, which I presume represent the work areas I would need to find myself to fix this issue.

Thoughts?

Thank you.

 

[TUDOR]

For a 45 year old tractor, belt condition and tension would be the first places to check.

Over time, V- belts stretch, the sides get glazed, and the tension spring anchor holes or indents get worn. The belt condition will cause slipping as it is warmed up, but the root cause could easily be lower than required spring tension.

Belt pulleys can wear, but that is a low order probability. More likely is the slight possibility that the 2-piece stamped steel pulleys have spread apart due to age, corrosion, and load at the V-groove and allow the belt to sink lower in the groove. The top of the belt should be flat with, or slightly proud of, the edges of the pulley.

 

[qbgLOVs7q]

For a 45 year old tractor, belt condition and tension would be the first places to check.

Over time, V- belts stretch, the sides get glazed, and the tension spring anchor holes or indents get worn. The belt condition will cause slipping as it is warmed up, but the root cause could easily be lower than required spring tension.

Belt pulleys can wear, but that is a low order probability. More likely is the slight possibility that the 2-piece stamped steel pulleys have spread apart due to age, corrosion, and load at the V-groove and allow the belt to sink lower in the groove. The top of the belt should be flat with, or slightly proud of, the edges of the pulley.

Tudor, thanks for the quick response.

So, as I look at the photo of that assembly I see two forward pulleys. But I do not see any type of tension spring. Ok...so I'll get into that area and poke around. Also, as I recall I replaced the drive belt two years ago...but I'd have to double-check that.

Anyway, thanks much for the push. I'll set aside some time soon to see what I can see. :hatsoff:

P.S. 47 years old...lol.

 

[Kbeitz]

I had that problem with a hydrostat and I fixed it with heaver oil...

 

[Dee_Veloper]

After 30 minutes does the engine still have full power ?

I'd be surprised if it's the pulleys. Seems like if it was the pulleys it would be a problem immediately. Belts could be the culprit as they warm up and stretch. Although again, once stretched they are always loose.

Check all belt tensions to determine if that is the cause.

I've had problems where power was fading after the engine was warmed up and it turned out to be the ignition system. I replaced the electronic ignition module and all was well.

 

[qbgLOVs7q]

After 30 minutes does the engine still have full power ?

It seems to, yes.

I'd be surprised if it's the pulleys. Seems like if it was the pulleys it would be a problem immediately. Belts could be the culprit as they warm up and stretch. Although again, once stretched they are always loose. Check all belt tensions to determine if that is the cause.

I've had problems where power was fading after the engine was warmed up and it turned out to be the ignition system. I replaced the electronic ignition module and all was well.

Ignition system? Interesting. Thanks for the suggestions. I hope to get a look at things yet this week.

 

[qbgLOVs7q]

I've uploaded some photos of the belt/pulley relationships for my tractor.

In thinking about what TUDOR stated at the outset, I notice that the inner belt, which I believe the Operator's Manual refers to as the "Forward Drive Belt," sits pretty much flush with the top (I say "crown") of both pulleys. This, apparently, is as it should be.

In looking at the same relationship but for the outer belt, a proper name for which I cannot find in the Operator's Manual, the three photos show that the belt sits well below the top/crown of all three pulleys.

The parts documentation I have indicates that both these belts have a 1/2" width at the top, which this outer belt does have (see photo). So, by my reckoning, this outer belt is either designed to sit very low in the pulleys, OR, all three pulleys have some degree of failure that is causing the belt to ride very low in the pulleys.

I'm not sure what to make of this situation, but it appears to me that nothing is out of whack. Still, I'm happy to have input.

Also, I do not understand the purpose of the unnamed outer belt. I gather, however, that the "Forward Drive Belt" determines direction of the tractor's travel: forward or backward. Am I correct? Is this adjustable? I mean, the tension on that forward pulley for the "Forward Drive Belt" appears to me to be sufficient when the Control Lever is engaged. But what do I know?

Again, further thoughts/direction is appreciated.

 

[TUDOR]

The belt that is sunk well below the edge of the pulley is either heavily worn or the wrong section (width), or the pulley is badly worn or spread.

V-belts drive by the friction between the sides of the belt and the pulleys. That one appears to be so far sunk that the bottom of the belt is now the driving surface.

That doesn't work for very long.

I suspect that the belt is excessively worn. A set of V-belt and pulley gauges will produce a definitive diagnosis. The gauges aren't normally found in Joe Average's tool box, but most tradesmen that frequent mechanical maintenance trade shows will have a set given out as advertising by Gates buried somewhere, or, an industrial supply house that sells a wide range of V-belts should have a set available for use at the counter.

The other option is to try the belt in a known good pulley and compare how it sits.

 

[qbgLOVs7q]

The belt that is sunk well below the edge of the pulley is either heavily worn or the wrong section (width), or the pulley is badly worn or spread. V-belts drive by the friction between the sides of the belt and the pulleys. That one appears to be so far sunk that the bottom of the belt is now the driving surface. That doesn't work for very long.

With that same belt so far buried in all three pullies, I find it hard to believe that all three have the same issue. I'm not saying that such a thing is not possible, just saying that I find it hard to believe. On the other hand, the belt is the correct width. Soooo, yeah.

The other option is to try the belt in a known good pulley and compare how it sits.

I actually have a disused 416S that I've been using for parts. I'll go see what it looks like over there and report back.

I suspect that the belt is excessively worn. A set of V-belt and pulley gauges will produce a definitive diagnosis. The gauges aren't normally found in Joe Average's tool box, but most tradesmen that frequent mechanical maintenance trade shows will have a set given out as advertising by Gates buried somewhere, or, an industrial supply house that sells a wide range of V-belts should have a set available for use at the counter.

I hope it doesn't come to that...lol. Alternately, I could just compare the one I have here and a new one, yes?

Thanks.

 

[qbgLOVs7q]

Just doing a quick look-see and touch on the pulleys/belt, it appears that the belt on my 416S does not go as deeply into the lower-front pulley as is the case on my 410S. I will note, however, that the belt appears to go in to the other two pulleys on the 416S as far as they do on the 410S.

Ok...so, sounds like I'll be doing some disassembly on the 416S and swapping out that lower-front pulley.

It seems prudent that, while I have things torn apart, I should compare all three of those pulleys to see what differences, if any, exist between the two machines.

Thanks loads, TUDOR.

Now to start a new thread for the "PHHHHH" sound the 410S produced, immediately after which it wouldn't start. It's always something....

 

[qbgLOVs7q]

I don't know if the verdict is in, but testimony so far has been very interesting. Let's go to the photos....

This lower-front pulley is NOT the same between the two machines. Perhaps this is to be expected, but I was surprised. In any event, the pulley from the 416S is not as deep (belt deep, that is) and not as wide (belt wide). Overall, the diameter of the pulleys is the same, but the 416S pulley is 75% narrower than the 410S.

I measure the 410S pulley to be 13/16" wide (judging by the wear on the interior of the pulley), while the 416S pulley is about 8/16". The one photo clearly shows that the belt is held much higher in the 416S pulley than in the 410S pulley. But I cannot say definitively that the belt is or is not bottoming-out in either pulley. But it certainly appears to me that the interior walls of the 416S pulley have a much greater level of contact with the sides of the belt than is the case with the 410S pulley.

Well, I've had my pulley/belt lesson for the day (I hope). I may take a look at that upper-front pulley...just to see.

Thanks to both TUDOR and Dee_Veloper for you assistance. (Now to figure out why the tractor won't start....)

 

[TUDOR]

With that same belt so far buried in all three pullies, I find it hard to believe that all three have the same issue. I'm not saying that such a thing is not possible, just saying that I find it hard to believe. On the other hand, the belt is the correct width. Soooo, yeah.

Yup, That's why I suspected the belt.

I hope it doesn't come to that...lol. Alternately, I could just compare the one I have here and a new one, yes?

Yes, that will probably work. Belts can sometimes be expensive and I prefer to confirm the problem before laying out my pension dollars on speculation. But then, I'm a retired industrial mechanic who did get to a few trade shows and have a set of V-belt gauges in my tool box.

 

[TUDOR]

Pictures tell the story. Someone swapped out the pulley at some point.

The one pulley is for A or B section belts. The other is for A section belts only.

 

[qbgLOVs7q]

Hey TUDOR?

I mounted the pulley from the 416S, and it's not quite perfectly in line with the other forward pulley. I'm a little concerned. But if I flip the pulley (note that it has that protrusion on the one side, which is currently outward-facing), that protrusion will be on the inside, thus taking the pulley further out of alignment. It sounds like I have no choice (I can't get the pulley any closer to the interior of the tractor), but what do you think? Concern or, no?

Thanks.

 

[TUDOR]

That depends on how slight the misalignment is actually. Ideally, there should be none, but in reality there is some wiggle room depending on how far apart the pulleys are located. Figure about an eighth inch per foot of shaft to shaft displacement and you should be good.

Note that the belts for LT mowers are operated at considerably more offset, but they are usually a lot easier to change when worn.

 

[qbgLOVs7q]

That depends on how slight the misalignment is actually. Ideally, there should be none, but in reality there is some wiggle room depending on how far apart the pulleys are located. Figure about an eighth inch per foot of shaft to shaft displacement and you should be good.

Note that the belts for LT mowers are operated at considerably more offset, but they are usually a lot easier to change when worn.

Ok...I'll maybe re-visit my work and see if perhaps I missed something. The misalignment is not much ("not much" being a relative term) but from the rear of the tractor, looking down the length of the belt, it is definitely not perfectly aligned. Hmmm...as I think of it, the mounting bracket-slash-belt guards that were used on the two different tractors were not identical. But one had some protrusion on it that interfered with the replacement pulley.

SIGH.

Oh well; back to it.

Thanks for the all help, TUDOR. :thThumbsU

 

[TUDOR]

I once had a wheel alignment tech tell me there was lots of play in the ball joints of my van and they needed changing. I told him that "lots" was not a spec. What is the actual number? They were in spec when he got out the dial indicator. He now manages the shop and reminded me of that conversation a couple of weeks ago. Now I know why I get service there that is above and beyond. :fing32:

The eyeball is a good measuring tool for rough alignment, but a straightedge is better for precision.

 

[qbgLOVs7q]

I once had a wheel alignment tech tell me there was lots of play in the ball joints of my van and they needed changing. I told him that "lots" was not a spec. What is the actual number? They were in spec when he got out the dial indicator. He now manages the shop and reminded me of that conversation a couple of weeks ago. Now I know why I get some things done for free. :fing32:

He must've learned something, considering you still do take your stuff there.

The eyeball is a good measuring tool for rough alignment, but a straightedge is better for precision.

For sure, but with bad eyes?!

Well, I took the tractor back out, and...yeah...no better.

I do find curious a few things:

1) Why is there no slippage in 1st gear?

2) Like I said in my OP, when going uphill, the tractor just stops: no engine bogging down, no wheel spin, no "WHIRRR!!!" or otherwise the smell of belt melting on the pulley. But when going in reverse uphill, the wheels spin, so then I stop. (And that was in 3rd gear, not 2nd and not 1st.) Why the difference?

3) If I very gradually release the foot brake so that the belt very gradually engages, I get a bit more "grip." Sometimes the "grip" is maintained, and I move. Other times, not so much.

So, the engine is NOT getting bogged down, the wheels are NOT slipping on the turf and there is NOT any smell of burnt/singed belt.

I'm so confused as to where the slipping is occurring. Would a belt replacement be the next thing to try? Maybe a pulley (or two)?

 

[TUDOR]

Things that make a tractor go:

- Shaft keys and key slots

- Pulleys (stamped steel pulleys have two parts, the hub and the pulley itself)

- V-belts

- Gears

- Tires secured to rims.

First gear takes less engine torque to get the tractor moving than any of the other gears. There is less strain on all parts of the drive train.

With the sole exception of a failed pulley weld, your symptoms indicate a failure in a rubber component. Is a wheel spinning without turning the tire? Possible cause is low tire pressure.

I'm running out of ideas. :bonk:

 

[qbgLOVs7q]

You're running out of ideas? Now I'm ion trouble...lol.

Anyway, to answer your question, the tire AND the wheel are spinning, usually in spots with no grass...just dirt.

All I can think of is the belt, especially as it appears that all the "heavy" components are working as they should (pulleys, gears, tires, etc.) Well, belts are relatively inexpensive (except at the local dealer) so it seems to be the least-expensive option to try.

Thanks.