Kubota B7800 Noisy in 4WD (Front)

rlray · Mar 24, 2009

Well I finally solved my L225DT front axle problem!!! (Sold it to a guy who only needed to brush hog)

I bought a 2006 Kubota B7800 HSD from a neighbor!! (Only had 75 hrs on it)

I notice that there is quite a bit on noise from the front whenever I have it in 4WD - Anone experience this?

Any gripes (fixes?) concerning that uncomfortable, forward sloping seat?

Thanks, Richard

Ken · Mar 25, 2009

Had a L3600 GST The 4whl. front end problem I had was the ring and pinion direct from the engine shaft. Then the reduction gears to hub There is a metal cap bottom of hub by removing this cap I found a 1/2 cup full of metal parts all having filtered past the bearings. so total rebuld of front axle. Know I have not used correct names of parts but to far from the book listing the parts. The price will make you walk with a limp for a while.
With a gringing noise in front end think it would be good to locate problem before gets worse.
Also went to TSC and bought a complete new seat did wonders for the back.
ken

36Tango · Apr 1, 2009

Ken said:
Had a L3600 GST The 4whl. front end problem I had was the ring and pinion direct from the engine shaft. Then the reduction gears to hub There is a metal cap bottom of hub by removing this cap I found a 1/2 cup full of metal parts all having filtered past the bearings. so total rebuld of front axle. Know I have not used correct names of parts but to far from the book listing the parts. The price will make you walk with a limp for a while.
With a gringing noise in front end think it would be good to locate problem before gets worse.
Also went to TSC and bought a complete new seat did wonders for the back.
ken

The front end on my B2400 is getting the same job done to it right now. Can I ask how much the damage was?

Yankee Clipper · Apr 1, 2009

rlray,

If the noise is only present in 4WD and not 2WD, likely you have an issue with the differential or ring and pinioin.

Drain the oil from the differential and see if there is a lot of metal - what kind / colr. Steel will be gray or silver and brass / bronze is yellowish.

If the oil is basically metal free, drop the driveline cover and collapse the tube to get at the roll pins on the drive couplings on each end. Drive the pins out and then slide the couplings to the middle and the shaft / cover will come down. Grab the front axle pinion and see if you can move it. If so, then likely the pinion bearings are loose or the nut backed off that holds the preload on the bearing set.

You may be able to tighten up the nut and restake it with a punch ("stake" means to upset some material adjacent to the retaining nut so it won't back off.) Jack up both sides and roll it over to check for noise or lack thereof.

I hope you find something easy - you did not say how old the tractor was but if less than three years old, you can get the Kubota dealer to do all this under warranty.

Good luck!

Ken · Apr 2, 2009

36 tango Rebuilt the front end after several Propellershafts broke and parts cost of 57.25 +shipping from Dallas to dealer then again to my address things were getting tense with the Kubota. Bought a repair Manuel to locate problem. book suggested to raise front end and check the front axle case bosses and brackets.If out of adjustment requires new front axle case. Took off the ring and pinion for front end diff. ground to being unusable.removed right front wheel hub metal parts bearings gone and bevel gears unusable. Looked at left side and same condition required total rebuild. Prices of parts less front end case came to $1556.00 This parts only. Had a local welder build up the case bosses front end always had Hydrolic fluid.replaced this with 80 weight gear oil
Hope your tractor is under warrenty.
ken

rlray · May 12, 2010

Wow! Where has the time gone? Over a year since I posted! I took my tractor in to the dealer... Tractor was out of warranty -- Service mgr. drove it & said some noise was normal & that it was probably the front drive shaft rubbing on the plastic cover -- ?? (Was not impressed with the service dept!)

Well, it's still doing it (maybe a just a bit worse) so it must not have been too bad...

I had somehow missed the replies from Yankee Clipper & Ken until today so I'm gonna take your suggestions & look for metal 'grindings' & go from there...

Ken - where can I get a manual? Sounds like you did the work yourself? Is it fairly straight forward to rebuild using the manual? I do have access to a local semi-retired mechanic/machinist I can go to for help if I get in over my head.

Wish me luck!

Richard

Ken · May 14, 2010

rlray. Not sure where you live but cannot be far from Clinton. have a book for my L3600 Kubota. But no longer consider being the owner. The hourly cost had became to much for the use. Placed on side of road as for sale. only one that stopped didn't have enough to purchase. So loaded and delivered to his address to use. He only puts hours in a year what I put on in a week.
Now to the problem of front end. There is caps and seal at bottom of axle that can be tapped off with a punch. this will show the metal that has worn off the gears and any broken parts if any. Removing and checking for metal will help in the deciding what to do.
If you are breaking the propeller shaft going to the pinion shaft or the retainer pins holding in place. check for wear in the front transmission shaft retainer boss held by 4 bolts on engine side and 2 bolts on front of center of axle.There is a adjusting bolt to correct in front.
If the front transmission is wobbly when front of engine is raised. look for worn housing the book says replace housing. Also with the pinion shaft if grinding when turned can be removed and checked for problems. Hope you locate and quickly repair the problem. Give me a call and can meet to loan the book. Not being neg. but expected more from Kubota. ken