CAT 245 Final: Must I pull sprocket ?

[Sockeye]

Hello Friends,

Our CAT 245 Excavator became broken (then, I came along).

Final drive gears were stripped. The CAT manual sequence of replacement starts with removal of the sprocket from the output shaft. However, I noticed that there is a retainer ring on the inside end of this shaft shown below (opposite the sprocket end). It appears to me that, if I remove this retainer ring, we'd be able to pull the output gear off this end of the shaft. The track, sprocket and shaft would remain in place (saving us tons of work).

* Is my theory a good one?

* Have you done this?

* What challenges might we face in pressing it back on from this end?

I've spoken to many. All have done it by the book because they could (they had facilities & tools and never questioned it).

I'm in town this week collecting tools and info. The worksight is remote and all I'll have is what I take out this week. Any insight would be greatly appreciated.

Thanks, folks.

Sockeye

 

[spitzair]

Wow, that's quite some carnage in there! I know nothing about 245 final drives, but looking at that picture it looks to me like the final drive gear is splined on to the axle and would probably slide off. Would it clear/fit over the bearing on the end of the shaft? Or could you pop that bearing off of there? Let us know how you make out!

 

[mitch504]

It looks worth a try; please let us know how it works cause I might have to do this myself someday.

 

[Cmark]

Interesting idea.

I can't say for sure, but I think you'll find that by design, the retaining ring can't be removed from the counterbore in the gear.

If you find you can remove the retaing ring, the gear should come off as planned. However you may then find that the springiness of the duo-cone seals makes it hard to push the gear back on far enough.

Also the weight of the track will be pulling the shaft out of alignment which will make refitting the cover difficult. I think you will have to remove the track whichever method you use.

Good luck...

 

[willie59]

I agree Cmark, and would add that given the amount of metal debris piled up in the pic, I'd wager that unit hasn't seen a good amount of oil for some time. Makes me wonder if the duo cone seal leaked the oil out. I certainly don't want to make your project bigger than it needs to be Sockeye, but given that amount of metal, it would be prudent to take the whole assembly apart and inspect all components, which would involve removing track and sprocket.

 

[Sockeye]

Good morning, Gentlemen.

Thanks for the feedback.

You have raised worthy concerns and insight.

As it stands, I believe we'll start by trying to remove this gear as stated. If complications arise, well, we'll just pull the sprocket anyway and resume with the book method.

I believe we will need to ensure the weight is taken off of the shaft to prevent it from teetering on the remaining bearing as CMark suggests (causing misalignment). Thanks, CMark.

When I got to it, ATCOEQUIP, it still had about 10 gallons of oil. Your concern was shared by others as well. Thanks for the comments and recommendations.

My guess was that the operator simply got it stuck in the rocks and mud and forced it. The track and car body were full, up to the cab, of grapefruit-sized rocks held together with mud and smaller rocks. These are tough machines but that's a hell of a lot of resistance. Something had to give..

I'll provide follow-up reports FYI.

Thanks, guys.

Sockeye.

 

[OneWelder]

It may have been low on oil ,usually there is some heat bluing with low oil level failures . but I suppose if it did not travel much it might not have gotten hot. Here are a couple of other reasons : On high mileage machine sometimes the hardness on the little gear will wear through- once this happens the little gear wears fast, filling the oil with a fine steel paste- then either the bearing wears enough or the teeth wear enough that everything breaks apart
which ever happens you end losing proper gear mesh= explosion

 

[JDOFMEMI]

Sockeye

For what its worth, I would doubt that the episode of being stuck caused the failure. It may have been the straw that broke thae camels back, so to speak, but hydraulic drive machines can rarely if ever put out enough force to break the gears unless there is already a serious problem.

I think OneWelder's explanation would be the likely culprit.

Also, with as much iron as there is inside the case, I think it would be prudent to go ahead and pull the sprocket so you can get at the bearing and seal behind it. With all that iron in there, even if the bearing is OK, the seal is likely ruined, and as you know, that may lead to a repeat of the same thing later on.

Good luck with the repairs.

 

[Sockeye]

Hello JD and 1Welder,

Thanks for the notes.

I'll bet you're right. Your comments resonate with another local comment one made here. I mentioned to him that there was another 245 near the mine. He said to forget about it. His justification: those crawlers were made to move the machine around the work site, not 20 miles up a trail which is what happens 'round here. He advised that you travel 1/2 mile, cool tracks and finals. The history of this machine is unknown by those of us now working it.

Thanks.

Sockeye

p.s. We'll pull the plug on the other side to look for shavings on the plug there as well.

 

[dsichewski]

when I worked with cat, if we saw a failure like that it would be an automatic rebearing reseal...as everything would be contaminated and for sure there would be a repeat failure. (seal leaking, bearing let go etc) Good luck on the repair and yes +1 on checking the other side final drive.

 

[John C.]

For a failure like that the machine isn't worth repairing with new parts. There are plenty of those old dogs around so use parts shouldn't be too hard to come by. Replace the soft parts with new.

Better yet, find a complete final and swap it in.

Good Luck!

 

[watglen]

I checked my oils this morning!

 

[JDOFMEMI]

Watglen

I have to say, I love your tag line.

By that method, I have succeeded!