853 drive belt replacement

[bkonn]

I recently purchased an 853 from an auction and it looks like the drive belt is cracking and brittle. I don't have a service manual and have never worked on this type of machine, Can someone kindley give me the steps to replacing the drive belt so that it will make my job a little easier. Also it seems like when I'm driving the bobcat foward that it seems a little jerky like it wants to buck me off, is this just inexpeirnce in driving or is there something wrong with the hydraulics. Thanks, Brian

 

[sterlclan]

I dont know about the belt but if it was loose that could be some of the jerking, with practice that goes away......congrats on the machine and welcome to the fourm.......Jeff

 

[Fishfiles]

To change a belt on a 853 , remove the overflow tank and the bracket that holds it to the wall for access , remove the plastic belt cover ,loosen up the 3/8 nuts on the adjustment rod on to the belt housing , loosen then remove the 9'16 headed bolt that holds the idler to the bellhousing and get the idler out the way , remove the belt from the pulleys , install the new belt , it barely fits between the front pulley and the wall , after the belt is inplace put the idler back in place , the bolt may be a little hard to get started and if you use a bar to pry down on the idler it will give a little more room to get the bolt in place and started , tighten up the bolt that holds the idler snug so the idler will still slide in place , adjust the adjustment bolt till you get the proper tension on the belt , this will be your hardest step as I would guess you don't have the bobcat belt adjustment tool , you don't want to get it too tight and by the same token not too loose , you can grap the bottom side the belt and get a feel for how tight it is , when you get it where you want it tighten the holding bolt and lock the jam nut on the adjusting rod -------------the 853 was not the best steering machine Bobcat ever made , they are a little jerky when moving around , what kind of tires are you running on

 

[bkonn]

To change a belt on a 853 , remove the overflow tank and the bracket that holds it to the wall for access , remove the plastic belt cover ,loosen up the 3/8 nuts on the adjustment rod on to the belt housing , loosen then remove the 9'16 headed bolt that holds the idler to the bellhousing and get the idler out the way , remove the belt from the pulleys , install the new belt , it barely fits between the front pulley and the wall , after the belt is inplace put the idler back in place , the bolt may be a little hard to get started and if you use a bar to pry down on the idler it will give a little more room to get the bolt in place and started , tighten up the bolt that holds the idler snug so the idler will still slide in place , adjust the adjustment bolt till you get the proper tension on the belt , this will be your hardest step as I would guess you don't have the bobcat belt adjustment tool , you don't want to get it too tight and by the same token not too loose , you can grap the bottom side the belt and get a feel for how tight it is , when you get it where you want it tighten the holding bolt and lock the jam nut on the adjusting rod -------------the 853 was not the best steering machine Bobcat ever made , they are a little jerky when moving around , what kind of tires are you running on

Thank you so much for your reply !!! I'm going to tackle this today, regarding my tires, they are severely bald and worn Nanco tires, I'm replacing them now with the Firestone dura force HD. I have a feeling that there are many parts that will need to be fixed or replaced on my bobcat so I hope you guys don't mind me posting my questions as this is all new to me. Thanks a Ton !!

 

[skidsteer.ca]

Thank you so much for your reply !!! I'm going to tackle this today, regarding my tires, they are severely bald and worn Nanco tires, I'm replacing them now with the Firestone dura force HD. I have a feeling that there are many parts that will need to be fixed or replaced on my bobcat so I hope you guys don't mind me posting my questions as this is all new to me. Thanks a Ton !!

Always help here. Just ask.
You may have a 3v or a 4v wide belt depending on serial #, make sure you get the right one.
Also check the belt tensioning idler for side play in the bearing. spec is .005" to .013" for new bearings. If yours is .025 or more might be a good time to re bearing it.
If its NOT the spring loaded self tension one, (you will see what looks like a rewind starter spring on it if it is) lay it on it backside, pop the dust cap off and make sure it is full of oil to the top of the bearings. Calls for 15/50 synthetic motor oil.
silicone the dust cap before replacing it.
Expect to re tension the belt after 20 hours or so breakin.
Also check the oil (80/90 gear ) in the 90 degee gear box that run the fan, lift the cab its in the center behind the operators back. They only hold a cup or so and running it out is spendy.
And while you at it make sure the spring loaded belt tension for the fan belt is not frozen. If the fan belts gets loose and slips you will overheat during high engine demand times. This one is easy to overlook.
Ken

 

[bkonn]

Always help here. Just ask.
You may have a 3v or a 4v wide belt depending on serial #, make sure you get the right one.
Also check the belt tensioning idler for side play in the bearing. spec is .005" to .013" for new bearings. If yours is .025 or more might be a good time to re bearing it.
If its NOT the spring loaded self tension one, (you will see what looks like a rewind starter spring on it if it is) lay it on it backside, pop the dust cap off and make sure it is full of oil to the top of the bearings. Calls for 15/50 synthetic motor oil.
silicone the dust cap before replacing it.
Expect to re tension the belt after 20 hours or so breakin.
Also check the oil (80/90 gear ) in the 90 degee gear box that run the fan, lift the cab its in the center behind the operators back. They only hold a cup or so and running it out is spendy.
And while you at it make sure the spring loaded belt tension for the fan belt is not frozen. If the fan belts gets loose and slips you will overheat during high engine demand times. This one is easy to overlook.
Ken

I was able to replace all 3 belts on my 853 in 7 hours, I started with the drive belt and everything was exactley as stated in the posted directions, it took a little over an hour to pull the old belt out replace with the new one, the 9/16th bolt holding the idler was the hardest to get started but with a little prying i finally got it. When I got to the fan belt that was a different story it seems that the spring that puts tension on the pully had become dislodged and was no longer keeping the fan belt tight it took me 3 hours to figure out that i needed to loosen the hex screw holding the pully so that I could re-align the spring into it's proper place. After that everything was a piece of cake. I'm going to check the gear box that runs the fan today and make sure its full of oil. Thanks alot for everyone help. Brian