Bobcat 763 Chain Case Drain Plug?

[HarryN]

Recently I purchased a Bobcat 763. Getting around to changing all the fluids and have come to draining the 9 gallons of oil in the chain case. The manual describes removing the "Drain Plug" and "washer". So I assumed you unscrewed the bolt and accompanying washer (like the drain plug on a car's oil pan) Not so.... This has a rubber grommet plugged into the drain hole!! (basically a rubber cork) For some reason this just didn't seem right, so I went to the local Bobcat dealer to buy another "Plug". That way I knew it would be the right item. To my surprise it is a "rubber grommet" with what looks like a nail you push into the center of it, which I assume expands the grommet to seal the hole and so it doesn't fall out. (there is no "washer" as described in the service manual??) My question is, Do you need a special tool to remove the rubber drain plug? Or, do you just rip it out of there? Being I don't have a lift... and barely no clearance as I get under the Bobcat, I guess you better be ready with a container for the have 9 gallons of oil that will be draining out!! Personally, I this this drain plug so is a poor design. But what do I know - LOL

 

[bobbie-g]

Harry. I agree, poor design, but it seems to work OK. No pressure to speak of on the plug. I put blocks under the back wheels to tip the machine forward, then open the fill plug at the front of the chain case (right in the middle, just behind the lift cylinder, maybe it takes a 1/2" drive ratchet extension to remove it??? I forget. Anyhow, get all you can that way, then go back to the plug-in-the-rubber-grommet. Just pull the plug out with pliers. Has a slight ridge on the backside of the plug, so you'll have to work at it to get it out. Then realize you should have had a large pan under there with you...... Glad you got a replacement grommet. I always like to have one on hand in case I mess up the existing one. Three other points: First, the grommet in metal is the chain case drain; beside it is the grommet into plastic which is the fuel tank drain. Second, the Big Boys tell me I really should take off the chain case cover and mop out the accumulated metal flakes and junk in the bottom of the chain case. I'm contemplating doing that on the next chain case oil change. Third, since that oil only lubes the chains/sprockets, the best of forum advice (from Tazza, I think, but then he's an Aussie...) is to drain the chain case before you change the hydraulic oil. Then just drain the used hydraulic oil into the chain case and save a few bucks. For us casual users, I question whether the chain case oil even needs to be changed, but I'm a maintenance freak so I do it just because. ---Bobbie G.

 

[Kermode]

Harry. I agree, poor design, but it seems to work OK. No pressure to speak of on the plug. I put blocks under the back wheels to tip the machine forward, then open the fill plug at the front of the chain case (right in the middle, just behind the lift cylinder, maybe it takes a 1/2" drive ratchet extension to remove it??? I forget. Anyhow, get all you can that way, then go back to the plug-in-the-rubber-grommet. Just pull the plug out with pliers. Has a slight ridge on the backside of the plug, so you'll have to work at it to get it out. Then realize you should have had a large pan under there with you...... Glad you got a replacement grommet. I always like to have one on hand in case I mess up the existing one. Three other points: First, the grommet in metal is the chain case drain; beside it is the grommet into plastic which is the fuel tank drain. Second, the Big Boys tell me I really should take off the chain case cover and mop out the accumulated metal flakes and junk in the bottom of the chain case. I'm contemplating doing that on the next chain case oil change. Third, since that oil only lubes the chains/sprockets, the best of forum advice (from Tazza, I think, but then he's an Aussie...) is to drain the chain case before you change the hydraulic oil. Then just drain the used hydraulic oil into the chain case and save a few bucks. For us casual users, I question whether the chain case oil even needs to be changed, but I'm a maintenance freak so I do it just because. ---Bobbie G.

I was just like you when I first encountered this. This has to be the stupidest design any manufacturer has ever come up with. Oddly enough, it seems to work. I have never managed to reuse the rubber grommet successfully though. They always seem to leak a little on me.

 

[biggie]

Changed mine a couple of times.I lift the back of machine up, and remove the cover at the front of the chaincase, and pump it out with hand pump. I get a good view of what might be happening in there.

 

[HarryN]

Changed mine a couple of times.I lift the back of machine up, and remove the cover at the front of the chaincase, and pump it out with hand pump. I get a good view of what might be happening in there.

After getting the drain "Cork", (still think that's a crazy design) I changed course and decided on Biggie's method. Plus I really wanted to see the inside. I removed the front chain case cover with eight screws (and removing the parking brake first) Used a rotary hand pump and easily sucked out most of the 9 gallons of old oil. Flushed it all out with diesel fuel (as recommended by local Bobcat dealer) using a pump sprayer. After that I just swabbed out the bottom of the chain case with rags. Made it nice and clean! Poured in 9 gallons of Rotella 15w40 and closed it all back up. Because this was the first time getting into the chain case, I think this was the best solution for me. The next time I can use the drain plug method as I'll be the only user of the machine. I took some pictures of it but don't see an option where I can attach them??

 

[Tazza]

After getting the drain "Cork", (still think that's a crazy design) I changed course and decided on Biggie's method. Plus I really wanted to see the inside. I removed the front chain case cover with eight screws (and removing the parking brake first) Used a rotary hand pump and easily sucked out most of the 9 gallons of old oil. Flushed it all out with diesel fuel (as recommended by local Bobcat dealer) using a pump sprayer. After that I just swabbed out the bottom of the chain case with rags. Made it nice and clean! Poured in 9 gallons of Rotella 15w40 and closed it all back up. Because this was the first time getting into the chain case, I think this was the best solution for me. The next time I can use the drain plug method as I'll be the only user of the machine. I took some pictures of it but don't see an option where I can attach them??

You did the right thing. You need to mop it out to get all the particles created when the chains and sprockets wear. I use diesel or kerosene on mine, works a treat.
For pictures, you need to host them somewhere like photobucket and copy/paste them into your forum post. If it messes up and you have the links, we will fix it up.

 

[HarryN]

You did the right thing. You need to mop it out to get all the particles created when the chains and sprockets wear. I use diesel or kerosene on mine, works a treat.
For pictures, you need to host them somewhere like photobucket and copy/paste them into your forum post. If it messes up and you have the links, we will fix it up.

Tazza. Here is one picture of the rotary hand pump in the bobcat to drain out the chain case oil. Checking to see if my first post of a picture worked?? Thanks for the tip.... http://i128.photobucket.com/albums/...763/th_BobcatChaincaseOilChange9-10-11003.jpg

 

[HarryN]

Tazza. Here is one picture of the rotary hand pump in the bobcat to drain out the chain case oil. Checking to see if my first post of a picture worked?? Thanks for the tip.... http://i128.photobucket.com/albums/p187/HarryHarley/Bobcat%20763/th_BobcatChaincaseOilChange9-10-11003.jpg

Tazza. I put the pictures on Photo Bucket as you mentioned, then did a right click to "copy image". Then "pasted" in the body of the post. And, that's how I got the small picture in the post. Is that the right technique? Is there something I can do to make the picture bigger? Thanks....

 

[Tazza]

Tazza. I put the pictures on Photo Bucket as you mentioned, then did a right click to "copy image". Then "pasted" in the body of the post. And, that's how I got the small picture in the post. Is that the right technique? Is there something I can do to make the picture bigger? Thanks....

To get the bigger image you will need to load the full sized pictue not just the thumb nail and right click/copy it. Everything else you did is correct.

 

[HarryN]

To get the bigger image you will need to load the full sized pictue not just the thumb nail and right click/copy it. Everything else you did is correct.

Ok Tazza, lets see if this works better.... more pictures that are full sized??? http://i128.photobucket.com/albums/...at 763/BobcatChaincaseOilChange9-10-11002.jpg

http://i128.photobucket.com/albums/...at 763/BobcatChaincaseOilChange9-10-11001.jpg

http://i128.photobucket.com/albums/p187/HarryHarley/Bobcat 763/BobcatDrainPlug.jpg

 

[OldMachinist]

Ok Tazza, lets see if this works better.... more pictures that are full sized??? http://i128.photobucket.com/albums/p187/HarryHarley/Bobcat%20763/BobcatChaincaseOilChange9-10-11002.jpg

http://i128.photobucket.com/albums/p187/HarryHarley/Bobcat%20763/BobcatChaincaseOilChange9-10-11001.jpg

http://i128.photobucket.com/albums/p187/HarryHarley/Bobcat%20763/BobcatDrainPlug.jpg

Sorry I forgot to mention I fixed your image in the other post.
It looks like your right clicking and hitting copy shortcut not just copy.

 

[HarryN]

Sorry I forgot to mention I fixed your image in the other post.
It looks like your right clicking and hitting copy shortcut not just copy.

So... that didn't work I presume. I'm using the free version of Photo Bucket, not the pro version. I'm uploading the orig images... does Photo Bucket re-size them to thumbnails? When I go there to right click on the picture, my choices are View image, Copy image or Copy image location. I tried both Copy image and Copy image location in the above posts and as you stated neither gave me a full sized picture in the body of the post... it that some thing I can correct or a setting I need to change? Thanks

 

[HarryN]

So... that didn't work I presume. I'm using the free version of Photo Bucket, not the pro version. I'm uploading the orig images... does Photo Bucket re-size them to thumbnails? When I go there to right click on the picture, my choices are View image, Copy image or Copy image location. I tried both Copy image and Copy image location in the above posts and as you stated neither gave me a full sized picture in the body of the post... it that some thing I can correct or a setting I need to change? Thanks

Oh, by the way, I'm using Firefox not IE. Would that make a difference?

 

[Tazza]

Oh, by the way, I'm using Firefox not IE. Would that make a difference?

I fixed them for you.
Firefox doesn't play nice with the forum software, not sure why though. I just use IE for the forum, everything else i use FF.
The oil was in a bad state indeed, that is not a nice colour at all.

 

[HarryN]

I fixed them for you.
Firefox doesn't play nice with the forum software, not sure why though. I just use IE for the forum, everything else i use FF.
The oil was in a bad state indeed, that is not a nice colour at all.

You are very observant! You are correct... the oil was in a bad state. The middle chain cover was missing 6 of the 8 bolts, so I assume some water got in there. Being that I just bought it and not knowing or believing what the previous owner said or did.... is the reason I've been changing ALL the fluids. And glad I did!

 

[Tazza]

You are very observant! You are correct... the oil was in a bad state. The middle chain cover was missing 6 of the 8 bolts, so I assume some water got in there. Being that I just bought it and not knowing or believing what the previous owner said or did.... is the reason I've been changing ALL the fluids. And glad I did!

On a new to you machine, its always a good idea to change all fluids and filters. You then know exaclty what has been done and when it was done.

 

[Ironwood]

On a new to you machine, its always a good idea to change all fluids and filters. You then know exaclty what has been done and when it was done.

This is an old post, but just to add, I simply put the front tires onto cinder blocks (solid ones) and lifted the back of the machine with my forklift (Bobcat chained to the mast) and lifted until the chaincase oil all draind out the front plug hole. I hoisted it pretty high, but it was EASY compared to the rubber gromet hole underneath. The little bit left I used a small oil suction mechanism to suck it out, them flush with diesel I shot in there with the same unit. I took the front access cover off to do the flush and final cleanout (obviously) then dumped the 9 gallons of fresh oil back in, Ironwood

 

[rodbuilder]

You're 100% correct. Maybe more than that! There isn't very much on one of these engineering disasters that isn't a poor design - starting with all the stupid safety interlocks. After all - how many safety switches doe it take to make it so we can't start the darned thing unless your butt is in the seat and the lap bar is down? Personally, I'm thinking ONE!!!

 

[7240]

You're 100% correct. Maybe more than that! There isn't very much on one of these engineering disasters that isn't a poor design - starting with all the stupid safety interlocks. After all - how many safety switches doe it take to make it so we can't start the darned thing unless your butt is in the seat and the lap bar is down? Personally, I'm thinking ONE!!!

I recently drained the fuel tank, and just backed the end of the machine over a slight drop off, and could easily get to the stoppers. I pulled down the metal pin in the middle with a pair of plyers and it came out ok. Just push the plug back in first, and then push the pin back up. It does not seem to leak. I want to drain my case next also. Does not appear to be gasket? Can one clean it out ok from the middle cover? My 1993 machine must be before all the safety switches, as it will start no matter where the bar, brake or seat is.