D8 14a finals

Yes I believe you can unbolt the ham cases and everything will come off with it after the bearing holder is free. We pulled the bearing holder by pulling on the sprocket. I was surprised it worked too. The sprocket is not free after this, there is still the big nut holding it on behind the bearing.
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The question is why are the gears chewed up? We just rebuilt a 14a with chewed up bull gears too.
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We found both dead axles were slightly bent causing miss alignment between the pinion and bull gear. If you put a fresh bull gear on you might chew it up too. If you decide to swap out pinion gears you have to pull the steering clutches. A puller is required to pull the pinion flange off the pinion while in the transmission case. We could not get the pinion and flange to come out together on a wet deck 14a.

This is the simple tool we made to check the dead axle for straightness. It has a matching centered lip to fit the bearing race. We could rotate the blue piece and watch the all tread move away from the dead axle.
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If your in this deep fix it right and be done with it!

Hey Team,

I have learned the hard way... All these older cats need to have the Finals torqued once a year back to spec. I was told up to 14-a and older models. Smaller tractors too. The 14-a with the most power on basic final design, would fail if not torqued to spec. I was informed to tighten the sprocket nut to 1200ftlbs once a year. If it starts getting loose it will bend the dead axle, then put uneven wear on bull gear. The pinion rides uneven on the bull gear putting strain on only a portion of the tooth rather than meshing the full tooth. The gears start to fail and chip off. That metal fragments then destroy the whole final and bearings.

All smaller cats need finals tightened too. I measured the front width (gauge) of tracks and compared the rear measurement. It was running an inch or more wider up front. I moved the tractor to a different spot and measured again. Almost 2" toe'd out. Started to ask questions. A seasoned mechanic instructed me to get right to the point and drain the oil from finals and see if any metal was present. Wow, lots of metal right side. So, I'm learning. Please all of you learn at my expense. Tighten your finals.
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All,

Back in 1970, the contractor I was working for had one of his 14as in the shop and was into the right finals. The pinion gear was really torn up but I don't remember seeing much damage to the bull gear. I have no idea if he tightened his finals on a regular basis. If the Cat books said to do it, he probably did. I also don't remember how much other work they did before it went back together.

I am wondering it the pinion goes first before the bull gear? I also do not remember what they thought was the reason for the failure. If they blamed me, one of the operators, I never knew about it.

JanM

Hey Jan,

That Employer and I conferred. Yep... Hahaha, why is it on your mind... Did you do it???

The way I see it, the design of the finals handled the strain along the D8 line from the early 8's up through the 2u's. When the 13-a came around and then the 14-a's, the horse power on torque started showing signs of failures on the finals. They changed design after the 14-a.

So, I guess after Cat realized Jan was tearing up Cats, they had to step it up a notch or two... Hahahaha

Hey Team,

Come to think of it, Jan did run my 14-a... And shortly after that... Rebuild time on the Finals... Something's never change... :doh:

Thanks for the prompt and in depth responses! Now I have no excuse to get at it. Other than the snow thats still in the yard and the mud. Cheers.

Glen/Mike, does the 14A have a single dead axle that goes from side to side, or one each side? What was the design change that Cat made with the 36A?

The 'H's had double reduction final drive, ie intermediate gear. Individual dead axles in all 8's

The dead axles on the D8H are much thicker than the 14A with a flange to bolt them tot he back end case inside the final drive, making the whole assembly stiffer, the outer track frame support bearing is a shim adjusted double taper roller, pressure fed with oil rather than the single bronze bush with 'sometimes' type greasing by the operator on the 14A.