MX4700DT nasty, expensive noises

[sunandsand]

Next door neighbor has an MX4700DT which he uses hard.

(He also hasn't read the sig line here about taking time to maintain your equipment or your equipment will make time for you to maintain it.)


Anyway, I stopped in today and he has the front of the tractor off the ground (using the front loader bucket) and a bunch of parts scattered around. Did I mention he's wearing a LONG face? Well he is . . .

Tractor runs fine in 2wd, runs ok in 4wd as long as it is going straight, but when you turn in 4wd, it makes nasty, expensive crunching and grinding noises from deep down inside the back end of the tractor.

Dealer cheerfully advises "Bring it down and we'll do diagnostics for you!" I'm sure they will, I'll tow it right down behind Dear Bride's Subie.

He's thinking he broke something at the rear end of the drive shaft to the front diff. I'm not so sure, because I'd think it would make noises in 4wd going straight as well, but I really don't know what's inside there although I'm guessing it is a) hard to get to (he's going to split the tractor in the next couple of days) and b) its going to be expensive (assuming he can even get the parts in some reasonable time frame).

I asked if he had found any metal in the gallons and gallons of hydraulic fluid he's drained out, and he said "No, not yet."

Open to suggestions . . . he's a good neighbor and I do want to help him if I can. I even told him I was willing to come get dirty this weekend if he wanted. He doesn't even need to supply beer, my beverage of choice is Diet Coke.

Best Regards,

Mike/Florida

 

[JWR]

Well,... the only way something changes when it is being turned compared to straight line is that the differential in the rear end is involved. So that says that inside the rear end there is broken hardware between the normal rear end function and the drive headed to the front end via the drive shaft. Not pretty to picture. That's why the thing is being split. Most Harry Homeowners with a tractor for fun are not ready to do that kind of repairs -- one wonders if he has the experience/ability figure out what parts are broken much less how to remove replace -- even of the logistics of getting the parts is solved. Good luck to your neighbor...

 

[sunandsand]

JWR, thank you, and that's pretty much what I expected to hear - major surgery, bring big bucks and have the manual at hand at all times.

I think he can do this (he's split the tractor previously to change the clutch), but I agree that it isn't going to be easy, cheap or fast. He's well equipped with tools and fairly competent in using them, so I think ultimately he will be successful. I'll make sure he has the torque settings and end play measurements available and help if I can.

Best Regards,

Mike/Florida

 

[big bubba]

diet coke? you deserve something with more substance for helping. cheers

 

[BeezFun]

I bought this inspection scope, helps a lot with diagnostics without always taking everything apart. It's waterproof and pretty thin so it fits in any filler or drain hole. It's nice because it's wireless so you can have one person poking it around inside while a helper looks at the phone or tablet screen to figure out what you're looking at.

 

[rScotty]

It sounds like he isjust getting started. If he did a successful clutch job then he is a decent mechanic.

Since the best way to start a repair is to do some simple tests to determine what is broken, so that's probably the stage he was at when you stopped by. It's probably what he was doing. I'd watch for awhile. Maybe you could get him to post here.

Most any mechanic can do basic diagnosis without any tools at all, though some are better at doing that than others.

Basic maintenance doesn't automatically mean failure. Over stressing, overloading, and yanking the controls around are what breaks things.

Basic maintenance can be as simple as checking the lubricating and cooling fluids and still be pretty successful. If the fluids are up to level and not contaminated....just unchanged, then my experience is that mechanical parts may wear faster, but not necessarily break.

rScotty

 

[5030]

Sounds to me like indiscriminate use of the locking rear differential to me. I bet the locking pins are sheared off and are doing damage in the rear case.

 

[sunandsand]

Noon Wednesday

Inspection scope is a REAL good idea - keeps from taking stuff apart needlessly.

Stopped by, he wasn't there, but he has the front axles out and the wheels are turned 90 degrees. I suppose that makes for a great turning radius. I'll report back on what he's found.

Best Regards,

Mike/Florida

 

[5030]

Why would you remove the front axles when the noise is in the back end?

This is gonna get interesting I suspect.

 

[sunandsand]

I have no idea why he pulled the front axles, but I will ask him later today. He wasn't there when I stopped by so it is possible he found something and has taken a ride to the Kubota dealer for parts.

Stay tuned . . . you're right, this may get interesting indeed ;-)

Best Regards,

Mike/Florida