My right track won't stay tight. I pulled the covers and cleaned it out and the seal around the tensioner shaft is bad. I'm hoping someone on here can give me instructions on replacing. Any help will be greatly appreciated.
Split track, push idler ahead, inspect idler extension rod for marks. If rod is good, pry out the old seal and install a new one. Reassemble carefully. Later Bob
Thanks Bob. I have zero experience working on heavy iron. From your experience would this machine have a master link. About how long should this job take?
Simple way to find out. Does one of the track links look something like the illustration on the right..? if so that's the master link. If not it is a case of having to find the master pin and press it out. Usually it has a dimple in the end of the pin where all the other pins do not. What Serial Number of machine are you working on..?
Thanks Nige. Ser no 78U33006S3600. Is it a 78 model?
According to my records S/N 78U3300 was manufactured mid-1977.
Would that year normally have master link. The machine is 50 miles away on my farm or I would just look. I have a lot of mechanic experience but none on heavy equip. Do you think I'll be able to replace track tensioner seal, and how long should it take? Thanks!
I suspect it's highly unlikely it has a split-type master link unless it is running a different type of chain now to the ones it was originally built with. So you have to assume you are looking at the need to push the master pin out to separate the tracks. There's plenty of expertise on HEF regarding these old girls and I'm sure someone will be able to walk you through the process of removing the master pin if you can confirm that's the type of joint it has fitted.
I had my helper look. No master link. Can someone tell me how to push out the master pin to split tracks on a 77 cat 931? You're talking to someone with no experience working on heavy equip so if this requires special tools, etc, I will probably have to rent or purchase them. Thanks
Your machine has a master link ,it might not look like a split link. A 931 came with either a sealed or a salt track,they both had a split link.after 35 years it has had the tracks changed.Look for a pin that looks different from the others,that one will have to be removed.If you could post pictures it would help.If your idlers are out to the end of the track frames you may have to remove a link. Good luck Bob
I do have a pin that looks different from the others. I will post pictures soon. I don't have a pin press or anything like that. Is there any way I can get that pin out without a press and if so can someone explain? Thanks
Safety Glasses all round, welding apron is good for hammerman, drift punch that will go through the pin hole with a long handle welded to it and a big sledgehammer. Later Bob
On my Allis, it took heat AND a 20# sledge a large cold rolled drift pin and lots of time for swinging:
I bought a 1 1/4" diameter section of cold rolled bar, cut down a piece of sch 40 1 1/2" ID pipe to hold it then welded the rig to the underside of a track shoe with spacer to center it on the pin, heat the ears of the rail segment of the master pin(both sides) pretty evenly then flail the hell out of it. The pin will need to be aligned to the drive sprocket area for access and support sideways to hold it secure enough to get it to moving. Your support tube and drive drift will need to be close to your master pin diameter but slightly smaller.
To get as much slack in the tracks as possible it's often a good idea to put a piece of bar stock in the top of the sprocket after opening the valve in the track adjuster and then gently move the machine in reverse until the adjuster pulls right back. Ease forward and remove the bar then you're ready to remove the master pin. The joint containing the pin should be about in the position shown in the photo so that you can a) use a wedge or a suitable piece of maybe 8x8 or 12x12 timber cribbing to support the link below the master pin (it also works well to line everything up when you come to put the pin back in again) and b) to use the sprocket as an anvil while you're beating the bejasus out of the master pin to get it out. Unless the "master pin link" can be held reasonably steady most of the energy you generate swinging the FBH will be wasted.
I forgot to add, I broke the BFH handle three times during the process, only brought my determination level up higher to hit it harder.
Thanks for all the advice. I'll be back on soon to let y'all know if I am successful. Thanks!
Those of us that don't enjoy swinging 20 pounders any more will core the ends of the master pin out with the gas axe or air arc, let it cool, then drive it out, usually with a few taps. Mind you this means you need a new master pin, but odds are it would be good to replace it anyway. Installation is usually easier than removal, still requires moderate heat and a fair bit of pounding.
When helping reinstall a master pin on a 955h we put the master pin in dry ice about 24hrs before we wanted to install then we heated all around the hole and that cold pin slid in that hot hole with about 4 or 5 good taps.
On mine, i just cut the chain off and got a new chain, the wear was so bad that i dont think it would come out, still have the old master links. my welder said he has welded the chains back together. sam.