743 axle seals and bearings

[donald r can]

can any one tell me do I need to separate the chaincase or remove the pump to do the front axle in my 743,i know you need to do it to do the rear but how about the front,im gonna do the front for now,i will do the rear later unless I have to remove the pump them I will do both,thamks

 

[Bobcatdan]

Pull the top cover off by your feet. That's the hole you will doing most the work from. Little trick on the sprocket nut. Put the wrench on the nut and jam it against something. Start the engine and turn the wheels in the propper direction to loosen. To remove the the axle, a flat porta power cylinder works the best. You can also use a bottle jack between the hub and frame.

 

[donald r can]

Pull the top cover off by your feet. That's the hole you will doing most the work from. Little trick on the sprocket nut. Put the wrench on the nut and jam it against something. Start the engine and turn the wheels in the propper direction to loosen. To remove the the axle, a flat porta power cylinder works the best. You can also use a bottle jack between the hub and frame.

thanks dan,ive seen kits on ebay with axle bearings,races,and seal for about 75 bucks per axle,these must be Chinese,anybody use these kits or should I use Japanese stuff

 

[Tazza]

thanks dan,ive seen kits on ebay with axle bearings,races,and seal for about 75 bucks per axle,these must be Chinese,anybody use these kits or should I use Japanese stuff

I'd rather go for quality, you don't want to do the job a second time.
The genuine seals aren't too expensive from the dealer. As for bearings, when you get the old ones out, you can get the numbers and get good ones from a bearing supply shop. I think I paid about the same for the ones I got for mine.

 

[donald r can]

I'd rather go for quality, you don't want to do the job a second time.
The genuine seals aren't too expensive from the dealer. As for bearings, when you get the old ones out, you can get the numbers and get good ones from a bearing supply shop. I think I paid about the same for the ones I got for mine.

thanks tazza,not to be a pain but ive read all the threads on this subject and am a little confused on whether to spit machine or pull the pump,why does the engine need to be pulled,is this to get the pump out,i have to check the rears for play,so still deciding if to do them now or not,they do leak a little so I know they need done,just money is tight now and I thought id get familular and do the front first,but if I need to remove pumps and engines then I might as well do all them,i got a price from dealer on stuff,80 dollars bearing,40 per race,i called my bearing supplier,used the numbers from here,thanks to tazza for that,59 dollars for bearing and comes with race,these are Japanese,not china,she can sell me china for half that but I think ill go with Japanese,bearing and race,dealer seal and wear ring,can my axle be welded and turned on a lathe if worn at seal area,i think one will be bad,or does this weaken the axle,i read here that you don't need to do that but how would the seal work on a grooved area,thanks don from ontario

 

[Bobcatdan]

thanks tazza,not to be a pain but ive read all the threads on this subject and am a little confused on whether to spit machine or pull the pump,why does the engine need to be pulled,is this to get the pump out,i have to check the rears for play,so still deciding if to do them now or not,they do leak a little so I know they need done,just money is tight now and I thought id get familular and do the front first,but if I need to remove pumps and engines then I might as well do all them,i got a price from dealer on stuff,80 dollars bearing,40 per race,i called my bearing supplier,used the numbers from here,thanks to tazza for that,59 dollars for bearing and comes with race,these are Japanese,not china,she can sell me china for half that but I think ill go with Japanese,bearing and race,dealer seal and wear ring,can my axle be welded and turned on a lathe if worn at seal area,i think one will be bad,or does this weaken the axle,i read here that you don't need to do that but how would the seal work on a grooved area,thanks don from ontario

If you need to get to the rear, remove the hydro. The engine and hydro are not joined as an assembly so there is no reason to pull the engine. The rear axles suck as there is no access plate above the rear axle so everything this is done threw the center opening. As for seal where, put a speedy sheelve on the shaft. I don't know what you are talking about splitting, there is nothing to split. Removing the upper structure from the chaincase is down right stupid.

 

[Tazza]

If you need to get to the rear, remove the hydro. The engine and hydro are not joined as an assembly so there is no reason to pull the engine. The rear axles suck as there is no access plate above the rear axle so everything this is done threw the center opening. As for seal where, put a speedy sheelve on the shaft. I don't know what you are talking about splitting, there is nothing to split. Removing the upper structure from the chaincase is down right stupid.

There should be a wear sleeve on the axle. If it doesn't look too bad, just clean it with sand paper. If it looks bad, replace them.
Not sure i agree with Dan this one, sorry bud. Access is horrible when you have to get to the rear sprockets. Remove the bolts, few hydro lines and lift pedal, the frame will lift up and you wheel out the chain case. This way the pump and engine stay in place and you can tip the chaincase up on it's end to make it easier to get the sprockets on the axles. I found this to be great as you aren't trying to hold the sprocket and chain up to line it up on the axle shaft.
I have done two, maybe three chain cases like this.

 

[Bobcatdan]

There should be a wear sleeve on the axle. If it doesn't look too bad, just clean it with sand paper. If it looks bad, replace them.
Not sure i agree with Dan this one, sorry bud. Access is horrible when you have to get to the rear sprockets. Remove the bolts, few hydro lines and lift pedal, the frame will lift up and you wheel out the chain case. This way the pump and engine stay in place and you can tip the chaincase up on it's end to make it easier to get the sprockets on the axles. I found this to be great as you aren't trying to hold the sprocket and chain up to line it up on the axle shaft.
I have done two, maybe three chain cases like this.

While I generally feel Taz knows his stuff, this one is whacky. Last time it came up, I brought it up to fellow Bobcat mechanics. All thought it was crazy to do it that way. I'm considered extreme in removing the hydro. Many do chaincase repairs with the hydro hoisted up 6" for room to get your arm under. I guess I look at as billable hours, I can do four axles in a day and half with pulling the hydro.

 

[donald r can]

While I generally feel Taz knows his stuff, this one is whacky. Last time it came up, I brought it up to fellow Bobcat mechanics. All thought it was crazy to do it that way. I'm considered extreme in removing the hydro. Many do chaincase repairs with the hydro hoisted up 6" for room to get your arm under. I guess I look at as billable hours, I can do four axles in a day and half with pulling the hydro.

well I don't know who to listen to as I believe both you guys are very experienced in this area,my local dealer in Toronto says they take the top off,i havnt had enough time to open the cab and look at whats involved either way,i have everything(I hope)coming and have some already,8 high end bearings,8 races,4 seals(from dealer as is the wear ring,or bushing,or what ever this item is called.it is in the parts breakdown and in the post of aftermarket numbers,this item had no other source so I got 4 of them and 4 seals at the dealer,as well as a few other things I needed,is this the part that you guys are speaking of,im very mechanically inclined but this job is a bit scary,i lifted the rear and theres a lot of in and out on the axles,is this bearing wear,not any up and down except one on the front,thanks guys I appreciate the help

 

[donald r can]

well I don't know who to listen to as I believe both you guys are very experienced in this area,my local dealer in Toronto says they take the top off,i havnt had enough time to open the cab and look at whats involved either way,i have everything(I hope)coming and have some already,8 high end bearings,8 races,4 seals(from dealer as is the wear ring,or bushing,or what ever this item is called.it is in the parts breakdown and in the post of aftermarket numbers,this item had no other source so I got 4 of them and 4 seals at the dealer,as well as a few other things I needed,is this the part that you guys are speaking of,im very mechanically inclined but this job is a bit scary,i lifted the rear and theres a lot of in and out on the axles,is this bearing wear,not any up and down except one on the front,thanks guys I appreciate the help

any special tools needed to pull the pump,sorry for all the questions but I havnt had time to pop the cage open,im gonna half to take the cage off because she wont fit in my shop due to height,i could take it to the shop at work but I cant leave it long and if I run into problems it can sit in my shop as long as needed,i read the manual I down loaded here years ago,it isn't that specific,doesnt tell about the pump or case removal,is it basically the bolts around the axles to separate if I go that way,thanks for the help

 

[Hotrod1830]

any special tools needed to pull the pump,sorry for all the questions but I havnt had time to pop the cage open,im gonna half to take the cage off because she wont fit in my shop due to height,i could take it to the shop at work but I cant leave it long and if I run into problems it can sit in my shop as long as needed,i read the manual I down loaded here years ago,it isn't that specific,doesnt tell about the pump or case removal,is it basically the bolts around the axles to separate if I go that way,thanks for the help

Best way to do it is take your time and go at your own pace. People do it different ways. Do it how you feel comfortable, NOT how someone else tells you how THEY do it. You have to remember, they have done it several and know their way around them. If this is your first time, take your time and gain access as needed. The fewer parts you remove, the less of a chance for something to go wrong. Most importantly, have the right tools. If these guys are telling you that you need a porta-power or jack to press/pull something off, dont show up with a pry bar and wonder why you cant get it off. If you get stuck, post up a question. The only stupid question, is the one that was never asked.

 

[7LBSSMALLIE]

any special tools needed to pull the pump,sorry for all the questions but I havnt had time to pop the cage open,im gonna half to take the cage off because she wont fit in my shop due to height,i could take it to the shop at work but I cant leave it long and if I run into problems it can sit in my shop as long as needed,i read the manual I down loaded here years ago,it isn't that specific,doesnt tell about the pump or case removal,is it basically the bolts around the axles to separate if I go that way,thanks for the help

if you are goining to keep unit. like forever. a complete chain case rebuild. is in order. to facilite this. without it being a great big pain in you know what. without standining on youre head or hangining from youre ankleles. and you only got to do it this one time should never have a need to do do it again. complete tear down. remove ldr arms remove eng. pull the stat separate main frame from chain case . this can be accomplished in about 6 hrs. now you got stuff you can deal with. clean it inspect it. renew worn parts . hoses ujoints brgs raceces etc. mind you this all on condition of pwr plant run a compression check on eng prior to anything. its real easy to put 3 grand in a unit that's worth three grand and than have to repower at 7 to 10. grand making final cost 13 that being said. a 743 with a good eng a gear pump not a vane pump. in good working order. will serve you well . they were a great unit simple strong and dependable . easy to repair. good parts availabity. ID HAVE ONE.

 

[donald r can]

if you are goining to keep unit. like forever. a complete chain case rebuild. is in order. to facilite this. without it being a great big pain in you know what. without standining on youre head or hangining from youre ankleles. and you only got to do it this one time should never have a need to do do it again. complete tear down. remove ldr arms remove eng. pull the stat separate main frame from chain case . this can be accomplished in about 6 hrs. now you got stuff you can deal with. clean it inspect it. renew worn parts . hoses ujoints brgs raceces etc. mind you this all on condition of pwr plant run a compression check on eng prior to anything. its real easy to put 3 grand in a unit that's worth three grand and than have to repower at 7 to 10. grand making final cost 13 that being said. a 743 with a good eng a gear pump not a vane pump. in good working order. will serve you well . they were a great unit simple strong and dependable . easy to repair. good parts availabity. ID HAVE ONE.

thanks for the replies,i have acess to many tools,including 3 or 4 large forlifts that can pick up 2 743 and lift them 30 feet in the air,i am keeping machine as ive had it for many years,its allways been reliable and the engine is strong,the machine needs some work but the biggest thing is this wheel bearing seals,i agree that I should replace the guts too,probally roller chain at the least,right now I coulnt afford it,ive spent a fair bit on her lately,bearings,seals,lots of other small parts,fuel lines,hard lines,battery,2 tires,new wear bar on bucket,gear oil,hydro oil,filters,you guys know what I mean im sure and this is not for business,its for my rural property,i might wait till spring or early summer so I can save some bucks for the inside of case and I do use her for snow removal.im just worried that I would score the axles,but I think they run on the wear sleeve so maybe I can get away with 10 or 20 more hours

 

[rodbuilder]

There's a guy on Ebay that sells OEM Bobcat bearing kits for a LOT cheaper than you will ever find them at a dealer. And save your time trying to find them at a bearing house because the "nice" guys at Bobcat bastardized the sizes on them, so you have to buy Bobcat stuff. The guy's user name is usedbobcatparts, but the bearings are all new. Welcome to America!!

 

[donald r can]

There's a guy on Ebay that sells OEM Bobcat bearing kits for a LOT cheaper than you will ever find them at a dealer. And save your time trying to find them at a bearing house because the "nice" guys at Bobcat bastardized the sizes on them, so you have to buy Bobcat stuff. The guy's user name is usedbobcatparts, but the bearings are all new. Welcome to America!!

I got the, bearings and races at a local bearing supplier lot cheaper and top quality stuff,had to get seals and wear rings at dealer,because of our dollar right now its crazy what things cost up here,with shipping its double what you guys pay so ebay is not a good deal right now for Canadians,gonna take my time and do it right

 

[Tazza]

I got the, bearings and races at a local bearing supplier lot cheaper and top quality stuff,had to get seals and wear rings at dealer,because of our dollar right now its crazy what things cost up here,with shipping its double what you guys pay so ebay is not a good deal right now for Canadians,gonna take my time and do it right

Dan has a good point, I didn't know you could gain access by just lifting up one end of the pump, do you need to pull the engine to allow it to tilt up?
Removing the chain case, you leave the engine and pump in place, you only remove the front two mounting bolts. It makes access nice, but for time, It may indeed be slower.
You didn't know which way to go, Dan does this for a living, I do it in my spare time. My way worked for me, but took time, his way will work too and will no doubt be faster.

 

[Bobcatdan]

Dan has a good point, I didn't know you could gain access by just lifting up one end of the pump, do you need to pull the engine to allow it to tilt up?
Removing the chain case, you leave the engine and pump in place, you only remove the front two mounting bolts. It makes access nice, but for time, It may indeed be slower.
You didn't know which way to go, Dan does this for a living, I do it in my spare time. My way worked for me, but took time, his way will work too and will no doubt be faster.

Other mechanics just unbolt the forward mounts, disconnect the steer linkage and lift the front of the hydro as far as it will go. I don't think they even disconnect the drive hoses. I saw that and said F that if I do one. The hydro that's a 1/2 hour to yank as long as hoses arn't little bitches. Chaincase repairs are one of the many reasons I hate 740 series. 30 series are worse, the cab doesn't flip on those bastards.

 

[donald r can]

Other mechanics just unbolt the forward mounts, disconnect the steer linkage and lift the front of the hydro as far as it will go. I don't think they even disconnect the drive hoses. I saw that and said F that if I do one. The hydro that's a 1/2 hour to yank as long as hoses arn't little bitches. Chaincase repairs are one of the many reasons I hate 740 series. 30 series are worse, the cab doesn't flip on those bastards.

I appreciate the input,its abig job and a little daunting to be honest,so i got some time to do some things she needed before the axles (which is gonna happen just might wait till better weather,as i cant lift the cab in my shop,and its real cold up here right now,ive had a bit of another problem with overheating,not so bad it would boil the rad but the gauge was reading high so i cleaned the rad,tigghtened the belt,and replaced the thermostat,question will it be allright to run without one,i put a new one in from the kobota dealer,and she heated up way to fast and hot for my liking,especially since its -20 here,so i pulled the stat and put her together and she ran on the low side of the gauge,will this be ok,neither the new stat or old one did anything when i put them in boiling water,the old one seems stuck a little open and the new one didn't open at all

 

[Tazza]

I appreciate the input,its abig job and a little daunting to be honest,so i got some time to do some things she needed before the axles (which is gonna happen just might wait till better weather,as i cant lift the cab in my shop,and its real cold up here right now,ive had a bit of another problem with overheating,not so bad it would boil the rad but the gauge was reading high so i cleaned the rad,tigghtened the belt,and replaced the thermostat,question will it be allright to run without one,i put a new one in from the kobota dealer,and she heated up way to fast and hot for my liking,especially since its -20 here,so i pulled the stat and put her together and she ran on the low side of the gauge,will this be ok,neither the new stat or old one did anything when i put them in boiling water,the old one seems stuck a little open and the new one didn't open at all

It is possible you have a bad sender or a bad gauge. I had a machine that was reading hot when it really wasn't. There was a flashing light on it that was drawing power and making the gauge go crazy.
If you get hold of an IR thermometer, you can check what temperature the thermostat is actually getting to.
You can run it without a thermostat, but the engine will never get to the correct temperature. I have heard stories of this making the oil sludge up from extend use like this as it is never at the correct temperature, true or not i don't know.