3416 H Smoking BGB

[Horvik]

Hello All;

I was cutting the grass(48"Deck) and all was well until something just did not feel right, and I noticed a hot burning smell. Put the PTO in neutral, pulled up the rear seat pan, and the left hand side of the BGB, PTO belt to deck was so hot smoke was coming off that. Also the belt was just as hot.

Pulled it up to the shop, removed the cutting deck , and it checked out fine. Removed the deck. Then I turned the driveshaft, both ends tight on the flanges, but I have maybe a 1/8 turn of slop (maybe more) in the BGB that was not there before. So at least I am happy I stopped to prevent any further problems to it.

This BGB was rebuilt not long ago, all new factory parts and always checked the lube in it.

So I thought before I get into the teardown, any of you fella experience this before?

All the best

 

 

[Bill725]

When the BGB was installed, did you add shims between the RH seal and the side plate so half the thickness of thick shim sticks out past the machined surface of the BGB?

[Horvik]

It's something that I need to check on though I did believe I put in the right shim amount.Could that make the play/make it run hot?

[PhanDad]

I'm curious as to the date you rebuilt the BGB.  I rebuilt one in July 2017 installing a new cross shaft.  In January 2022 the cross shaft seal was leaking on the PTO side when under load (snow blowing) -  90 hours after the rebuild.  I still suspect the new cross shaft was defective - either wrong material or not heat treated at the needle bearing location.  Hopefully that's not your issue.  This post has pics of the failure:

https://simpletractors.com/forums/topic/66821-agco-allis-918h-bevel-gear-box/#comment-534394

 

 

[SmilinSam]

PTO clutch cap getting worn? 

 

If the belt is that hot,  the heat has to be coming  from somewhere close to the belt .  If the cap is geting worn, it could be slipping enough that its getting the pulley hot but not enough to keep it from mowing grass.

A sticking idler pulley can also generate a bunch of heat

[Horvik]

Hello PhanDad... Good point on the seal gap causing a leak , read up on your link and is surely food for thought. I would estimate the rebuild has less than 25 Hours on her.

SmilinSam...When you say PTO clutch cap, do you mean the friction cone clutch ? if so it appears to have a good bit of lining on it. The idlers seem to spin freely.

I still am dealing with the fact that after the rebuild it had minuscule lash on the gears, tight. Now it has too much in it. So I will have to further investigate.  

 

[Horvik]

Bill725;

Would the shims you detail, if incorrect, create the increased  lash?  In turn would this heat things up considerably?

 

[hurleyii]

I’ve had this happen on my sovereign and I lost the bearing in PTO itself This destroyed the entire PTO assemblies. . I had to steal from my 7100 series again for the same tractor!! Lol The not funny part is I have the same play in my Sovereign BGB now and the seal is leaking. My theory the  pto bearing failed  over heating the seal and causing a gear lube leak and eventually overheating the bearing causing a bearing failure. I have so much dust inspecting for leaks unless bad is impossible. 

[acken]

I can't see too much backlash on gears would cause heat out at the belt.  They would make excessive wear on gears.  Did you seat cross shaft when you rebuilt the BGB?  I use a brass hammer to tap shaft back and forth after everything is assembled, and nut on RH side is torqued.  Double check your fluid level, and remove any load on BGB both sides.  Then rotate by hand to see if any bearings feel rough.  If that seems OK, reinstall everything, check idler bearings also.  Then I would run the mower deck for short time to determine where the heat is starting from.

[Tarheel]

 Not addressing the slop in the bgb (1/8th turn seems huge to me) I have a feeling that the heat is likely caused from a slipping belt. (or slipping clutch but a clutch gives off an odor like heated brakes on a big OTR truck. If you have ever smelled it, you'd remember I'd think.)

 Being that the belt got that hot, I'm pretty sure it will need to be replaced anyway. I'd replace the belt, check to make sure the tension on the spring was right and run it for a bit then check for excessive heat.

 Many of these guys know far more about the bevel gear boxes than I do. But I can't imagine one getting hot enough inside to heat up the belt to the point of burning it and I can't understand why all the heat went to that side only and didn't overheat the transmission belt.

Good luck with it.

[hurleyii]

2 hours ago, Tarheel said:

 Not addressing the slop in the bgb (1/8th turn seems huge to me) I have a feeling that the heat is likely caused from a slipping belt. (or slipping clutch but a clutch gives off an odor like heated brakes on a big OTR truck. If you have ever smelled it, you'd remember I'd think.)

 Being that the belt got that hot, I'm pretty sure it will need to be replaced anyway. I'd replace the belt, check to make sure the tension on the spring was right and run it for a bit then check for excessive heat.

 Many of these guys know far more about the bevel gear boxes than I do. But I can't imagine one getting hot enough inside to heat up the belt to the point of burning it and I can't understand why all the heat went to that side only and didn't overheat the transmission belt.

Good luck with it.

I believe this is correct. Your problem has got to be outside of BGB as far as belt issues go. Could be bad bearings on deck or plastic bag wrapped around a spindle. Lost my 60” deck belt from a rope  that wrapped around a spindle two weeks ago on my sunstar. 

[ShaunE]

On 6/26/2024 at 6:29 PM, PhanDad said:

I'm curious as to the date you rebuilt the BGB.  I rebuilt one in July 2017 installing a new cross shaft.  In January 2022 the cross shaft seal was leaking on the PTO side when under load (snow blowing) -  90 hours after the rebuild.  I still suspect the new cross shaft was defective - either wrong material or not heat treated at the needle bearing location.  Hopefully that's not your issue.  This post has pics of the failure:

https://simpletractors.com/forums/topic/66821-agco-allis-918h-bevel-gear-box/#comment-534394

 

 

This is my biggest fear. Sitting with a couple NOS input & cross-shafts & gears for the future with a sixth sense that they aren’t hardened on the bearing surface. 

[Horvik]

Thanks a lot for all of the good ideas to help me along with this problem. I can't help but think on the other 3416 H I rebuilt the BGB 14 years ago and never had a single problem with it. 

So that might mean I have bad parts in it? Anyone that orders briggs parts knows that a real good question. Here's another from me. I know I can dig out an old used but good BGB. Of course you should replace the three seal in the unit. BUT, would you do so far as to disassemble the entire units, as in checking the torgue on the pinions bolt? Just wondering . I don't know of any other way to thoroughly check one of these without totally removing it from the rig.

Your thoughts are appreciated!

[Tom45]

I would at least remove the rear cover to inspect it and check for looseness or problems.  Sometimes it is just a matter of the woodruff keys being worn.  

[Horvik]

Hello;

This is a followup to my original post including the findings. The nomenclature is left and right as seated on tractor.

1. The nut (left side)securing the cone clutch was finger loose.

2. Grease is leaking out of the right side where the hydro drive sheave is located. NOTE: the "spacer" to the left of the hydro drive sheave does NOT turn with the shaft. to me it certainly should. Of course this is going to comprise that grease seal on the right side.

Thoughts and questions; To me the loose nut and hence loose cone clutch will certainly make the belt hot and bgb smoke right there.

Question: Does in any way the left clutch nut being loose affect the internal; gear backlash?

Appreciate the help