I have a D37EX-21A dozer and the left track won't keep tension. I don't see any grease coming out anywhere. Does this sound like a seal problem? Anyone have a better idea? Thank you!
Adjust the track, then mark with paint or something where he idler block is then run it until its loose again. This will tell you if the cylinder is holding or not........or you possible have severe wear in the track rails or framework. The adjust cylinders can leak internally or externally.
How worn out are the tracks? If the front idler support blocks have reached the ends of the track frames and the idlers are bouncing up and down in the guides, your adjuster cylinder most likely needs to be rebuilt when you put the new chains on.
It looks like the cylinder is just not keeping the idler pushed out -- that is, the idler moves back after a few minutes of use, leaving the track loose. It sounds like it's leaking internally because I don't see any grease escaping. But, I'm sure I don't fully understand it because I can't explain where the grease that I'm putting into it is going. Thank you!
Once the cylinder barrel is full on both sides of the piston rod it will push the wiper seal out. Sometimes, depending on the design of the cylinder, the escaping grease falls in between the rails where you cant see it well. In either case, its time to pull it apart and fix it here while we all give you guidance and moral support! LOL
Maybe the grease fitting or release has come loose a little and not holding pressure? Not sure if you've taken any covers off to have a closer look.
And I sure need all the help I can get! I see no grease (or anything else) coming out around the fitting or anywhere else. Ive been searching for a part number for the piston seal and can’t find it. If the most likely problem is a bad seal, I’d like to have one on hand before rilling it apart. Does anyone have a part number or diagram with part numbers? Thank you.
Am I looking at the right assembly here:
That's just the idler assembly. The track adjuster and recoil spring are mounted inside the track frame behind the idler. Now I have to wonder where you are trying to adjust the track at.
I had a hunch I wasn't looking at the right part. I'm adjusting the tension behind plate 7 in the diagram below. I just haven't found the page in the parts manual for the track adjuster.
You are in the right spot then. Keep paging through the book and you will see a big spring. The track adjuster cylinder with be on the back of that.
Neither of these?
Item 1 is the cylinder, Item 18 is the rod. The seal is item 12 and you will also need the bushing, Item 2. I'm not sure of what all the other rings are but you will see when you remove the whole assemble. Item 18 will just pull out of the cylinder assembly. There is a large nut on the back of the spring, Item 5. Don't touch that.
I went ahead and ordered numbers: 2, 18, 12, 15, 16. Do I have to remove the track? Master pin or key shoe? Thank you!
You have to look for a split master link. Track has to come off to repair adjuster. I guess you could try remove the track at the idler but still a big pain to get back on.
They don't use split master links on these small machines that I have seen. There will be a master pin that has a partial hole or what you would refer to as a cut out for a lathe center. You are supposed to put the pin in the track with the dimple facing the outside of the machine but many times put them in backwards and you have to look at the track from under the machine to find it. Get a new master pin for the track and just burn the center out of each end of the one in there and knock it out with a four pound hammer. I have attached of photo of how I cut the master pin for removal. I split the track with the master at the idler end and then back the machine up just enough that the top end of the track is behind the front idler. Don't throw the old pin away as you can use it for a line up when you go to reassemble the track. Good Luck
Wow, that's great detail. I previously looked for the master pin (from the outside) and could not find it. Any chance you have a picture of what the "partial hole" would look like? If I find it, would I still need to new master pin? I'm not clear why and when the burning out of the center of each would be done. Thank you!
I can't tell if the pin identified in the diagram (item # 10) is the master pin or a regular pin. And, it looks like there are plugs in the end (#11 and #12).
This picture shows a sealed and lubricated track. 3&4 and 5&6 show a master link look for a solid link . You take the pad bolts out and the link comes apart. Bob
So I don't bang the pin in and through? How can I tell which pad to take off? Thank you!
Look for a solid link! Called a master link if you have one you don't have a master pin so you won't have to drive a pin. Bob
Hopefully you have one that looks like this one.
Do you have a serial number of your machine handy. A split link would be a Berco style and not the alligator links shown above. Your part diagram show what it looks like.
yes, that would be great. Serial number 5735 Attached is a photo of the plate. Thank you.
I apologize on the instruction for removing a master pin. You machine is a 2007 model which is a little young for my time. Slack of the track and position the master link at the lower position of the idler against a block. Take out the four bolts and remove the pad. Now you can back up enough that the top part of the track is pulled back behind the idler. Leave the block in place and you can usually roll the idle out a bit. You will need to support the spring with something overhead as you come out of the track frame. The fork piece being talked about earlier that fits into the track adjuster grease fitting usually has to come off before the idler and spring will come all the way out.
No need to apologize at all -- I am incredibly grateful for your help. But, I can't say I fully understand. Have I got this right: First, find and position the master link where I drew the red arrow on the image below. Remove the master link and back up so the track is completely off the idler. I don't know what block to leave in place or how to support the spring from overhead or what fork piece to remove in order to get the idler and track adjuster completely out. Do I need to remove the idler completely to replace the seals on the adjuster? Thank you!
Correct! The wood block will go right below your arrow. It will hold up the bottom part of the link to assist you going back together. It will be a master pad if you have SALT tracks (I'm assuming you do). It will be a master pin of you have dry rails. The master pin will have a detent in the end of the pin the other pins dont have. Correct again! Usually done with a small crane or chain hoist anchored to something above. Forklift would work to. The fork piece is the idler yoke. It will come out as an assembly bolted to the idler. You will see the set up once the assembly is removed from the track frame. The yoke will be the cylinder barrel and the rod will be sticking out the back side (chrome rod). You should be able to twist and turn the rod by hand and slide it out of the barrel. The seals will be inside the barrel itself, and......depending on the manufacturer, there may be seals on the piston end of the rod.
Although the tracks in your picture are a newer style than yours look directly below the idler and you will see a solid link ,this is what your master link will look like. You don't have to remove the link just the pad. Going by your questions you should consider hiring someone to do this job for you. Good luck Bob
Just an update: Sprocket is replaced. Getting track off wasn't too bad at all. Digging the seal and collar out of the cylinder was a PITA. Getting the piston back into the cylinder required a sledge. But, it all works well now. Thank you all again very much!