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hoodeleydoo

t340 sprocket advice

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hi all!

need to pick ur brains....

my t-340 that I just overhauled the engine on has a bit of an issue with the tracks and sprockets. the tracks are berco's and visually look good. i didnt measure the wear yet (with gage etc). however when i was moving snow a couple months ago I didnt get very far as the track would bind up at certain points (not continually) and the resistance to moving was extreme. i thought it was because the tracks got bound with snow and ice and dirt, so i released the track tension a bit - but it still would bind at certain points. extreme to the point that I feared for the final drive bearings and housing. after much investigation I found that the pins and bushing are all still "round" and about he same distance apart - but some sprocket teeth were hitting the bushing squarely on the bushing and not meshing properly. first thought was worn pins, second thought was worn sprockets and bushing. well turns out the sprockets has some non-uniform tooth wear. see the pics. not sure why this is happening other than that the track pitch and the pitch diameter of the sprocket are perfect for the bushing to hit the same sprocket tooth all the time (even # - not progressions). I was thinking of several subsequent actions:

1) providing that the same tooth get the bushing each time, rotate the engagement of the sprocket one tooth and go to the "un-worn" teeth. would also need to verify that the sprocket  wear is systematic and not random. 

2) grind down the tip of each "bad" sprocket tooth to engage properly

3) take off the sprocket and weld/machine/grind back to mate to the existing tracks.

4) maybe some of the other spare sprockets i have will fit better.

 

I'm really hoping for option one or two as I have to get some work done WITH the machine and no longer ON the machine!!! (haaa)

of course option 3 would be the most interesting (and expensive) but I would need to get info on the materials, geometry, and hardening. when I got the machine someone had put some work into the tracks (i think it was running well at that point - prior to being submerged) but had the tracks SUPER tensioned. wondering if that was the fix or possibly the cause. dont have much time to think about it these days - nor play around.

thanks!

1.jpg

1.jpg

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If the sprocket pitch is worn from the bushings always running in the same place, can't you index the sprockets 1 tooth to get back to the correct pitch?  Something isn't right, though as they should be alternating....

 

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I'm wondering if the wear on the sprocket teeth, especially on the one side of the tooth, is not holding the chain in the right position as it comes around to engage the next link.

Assuming the chains are the right ones for the machine.

 

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so i was able to spend some time and investigate. one sprocket has very random wear and a bit more than the other (this is the one causing trouble) however in general most wear was every other sprocket valley. I suspect that sprocket was used prior to being installed on this one. the other sprocket looks quite good comparatively.

so i marked the sprocket tracks for those receiving the bushing and drove around for a bit - no progression - so verified that the same sprocket locations always get a bushing and the adjacent never does. so it must be an even number of sprocket teeth. 

so i am going to go with option 1 listed above and try to change the location as well as throw in a little option 2 and grind some of the worst offenders. we'll see how it goes and at least prove the concept. when I progress the tracks I'll check out the condition of the "new" valleys and go from there -  I need to investigate my other machines to see if any sprockets are good. 

 

so i also want to look into number of teeth - i think the later ones have an additional tooth (solid versus spokes) but not sure - ran out of time before I could check. 

 

maybe the parts book lists it.....

 

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i also think that the prior owner tightened the **** out of the tracks to try to overcome that issue. could have played a tune on the tracks they were so tight....

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If you haven't ...

you should count your links...if somebody has removed a link to shorten the chain it will cause this type of wear 

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so i rearranged my schedule and worked on the dozer this evening. so my track tension gear was pretty clean and i was able to loosen it up enough to fully retract the idler wheel with gave me just enough room to manhandle the tracks over one sprocket tooth.the sprocket is definitely worn non-uniformly but the new position is much better then the existing. i retentsioned the track and took her for a ride. MUCH MUCH better. PHEW!!! now i just need to get some drive clutch adjustments done, keep going thru commissioning trials and rebuild the loader and bucket........

 

i also need to measure up the bushings and figure out if I should consider turning them soon.

 

the drain hole drilled into the bottom of the exhaust manifold needs to be plugged - its getting soot all over the engine and add to the noise. i think its heating up the carb too.

 

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On ‎6‎/‎13‎/‎2018 at 12:29 PM, hoodeleydoo said:

so i rearranged my schedule and worked on the dozer this evening. so my track tension gear was pretty clean and i was able to loosen it up enough to fully retract the idler wheel with gave me just enough room to manhandle the tracks over one sprocket tooth.the sprocket is definitely worn non-uniformly but the new position is much better then the existing. i retentsioned the track and took her for a ride. MUCH MUCH better. PHEW!!! now i just need to get some drive clutch adjustments done, keep going thru commissioning trials and rebuild the loader and bucket........

 

 

 

...first  thought, upon reading your post, was......are those chains the correct length....i.e.   center to center of bush.......given that visual of the sprocket  ...that tells me that your track chains are far from worn out......and reading the above quote confirms my initial   thoughts .......

There is no way the sprocket can wear  ''  non-  uniformly''   (quote)...if your chain /sprocket  assembly.   are matched......  they will wear out...!!  but uniformly...  and if the previous  owner had tensioned those tracks up  really tight.....an   incorrect dimension link.........either to long  or...to short....  would have the effect of a tooth eventually wanting to hit a bush...bang on.......and as for the 'incorrect dimension "....we are only talking  a fraction of an inch...maybe one sixteenth or so...that is all it would take.........conversely   ...if  by some unbelievable  piece of stupidity...an incorrect sprocket was installed, I guess you would see similar symptoms.......

Find a data sheet for the machine track specs and progress from there......my thoughts

Mike

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I'm with Mike, wrong chain or sprocket but, and I know nothing about the 340, maybe worn/bent dead axle or track frame mountings??   Plowing snow is extremely hard on tracks, snow will pack in the link so tight it will break something.   

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T-340 sprockets have 26 teeth, 1- 7/8 in. wide, 35 shoes each side. The sprocket teeth engage on every other revolution. (Hunting tooth) You need a chassis service manual, it will give you the maximum allowable wear and pitch of the chains, pins, rollers etc.  Maybe mmi has that info.

IH T-340 tracks.jpg

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Hey hoodleydoo I see you're not too far from me.i gather from reading your various posts that you have a parts machine or two. I'm looking for a complete engine to put in my t-340. Would you happen to have any or any t-340 parts available?

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Hi. 

I have some parts but most are needed or spoken for.  Send me a PM and we can discuss. As far as t-340 parts -as far as engine parts - my suggestion would be to investigate going with the later serial number engine series.  I beleive they rotate in the same direction and bolt up properly to bell housings and trans input shafts.  The parts are easier and less expensive to find.  I will be doing that on my next t-340 build and replace the lower serial 135. However the engine i just rebuilt is a nice runner and has plenty of power.  It’s just things like all bearings, heads and pistons are hard to find ( good quality ones).  

 

In in regard to the original post I have about 40 hours on the dozer now and I found out the issues of the tracks.  First, the tracks are not worn consistently over the sprocket.  The number of teeth are even so every other sprocket sees a link every time whereas the alternating sprockets never see a sprocket. No progression like in the later 340 models. So I picked the nicest teeth to run in.  Secondly, and most influential, was that I had a couple of stuck pins. When I say stuck I mean STUCK. lickily they were stuck in the arc of the sprocket so driving was possible. This is how the tracks loosened and tightened as the machine drove.  Well after loosening the track just enough to prevent damage and applying kroil continually, all the right pins loosened and now the tracks are perfect! I’m continually tu big and adjusting as I commission the unit but getting more work done and please with the performance   The next issue is to adjust clutches and then rebuild the ripper   

Thanks for all the advice  

of anyone has any questions let me know 

thanks 

Kevin

 

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