Stuck track tensioner on a 450

[tjdub]

It was time to re-tension my tracks on my 450. I've done this twice before and it worked fine each time. Now this time one of the tensioners won't take grease. I Lifted the front of the machine up with the blade and used a bar to verify that nothing was binding to keep the front pulley from sliding. It has to be the tensioner cylinder that is binding internally. I took a pick and cleaned all the dirt out from inside the tensioner seal, but it still won't budge. It was only a few months ago when I tensioned it last, so I'm not sure what happened.

What's the best way to break it loose without breaking the grease seal? I've read enough stories about breaking the tensioner seal by using the 6-way blade and a block of wood to force some grease out, so I'm thinking that is the last option. Should I find a grease gun that can deliver more pressure, or maybe use a little heat?

[vestor_guy]

First make sure the grease fitting is clear and will take grease. If it will take grease, then the tensioner rod is frozen in the cylinder. The function of the outer seal and the second grease fitting is to keep the rod and cylinder from rusting, by keeping the grease in and the moisture and dirt out.

The first step I would do after I determine the grease fitting is clear is to remove both grease fittinga and see if the track will slacken. If it wont, it is frozen and that is where the block of wood between the blade and the front idler comes in play. If you get it broken free, the replace the main grease fitting and see if the tenssioner will extend.

[tjdub]

Thanks for the tips. Grease flows through the zerk fine and out the bleed hole when I open that bleed screw a little.

I tried the block of wood trick and I after a few tries I got the cylinder to retract and spit out grease. Unfortunately, it still won't take any grease

Is there anything else to do other than find another tensioner? I may try to find a grease gun than can deliver a bit more psi than the one I have, but I'm not holding out much hope on that front.

[vestor_guy]

Sounds like you may have a problem with the grease gun. That would be my next step. Deere made a low pressure gun for the lubing the track idlers and rollers. Is that the gun you are using?

[tjdub]

Sounds like you may have a problem with the grease gun. That would be my next step. Deere made a low pressure gun for the lubing the track idlers and rollers. Is that the gun you are using?

No, it's just a pistol-grip grease gun. I can't find my lever-style grease gun which would give me more pressure. I'm sure it will turn up just as soon as I buy a new one though.

I have the back zerk out of the tensioner and a pool of penetrating oil sitting in the hole. Fingers crossed

[gerald]

Tjbud. I found when rebuilding my adjuster, the port hole from the sert was gulled closed with iron. I drilled it out. There is a ball bearing under the bleed off bolt with out that it won't take grease .

[digitup2]

I have a high pressure grease gun and for more pressure than that I use an old leaver action hydraulic pump So far that has moved anything I have hooked it to when things break lose the hydraulic oil tends to fly .Digitup.

[tjdub]

I got it loose!

First I got a new heavy duty lever-action grease gun. I figured even if I found my old one, it leaks a little and probably wouldn't do the job. (still haven't found it though for some reason).

After 24 hours of the penetrating oil soaking in the hole for the rear grease fitting, not a drop drained out. I tried the new grease gun on the cylinder but didn't have enough muscle to budge it. I put the fitting back in hole that the penetrating oil was in and it didn't seem like I was able to put any grease in there either. I pulled that fitting out again and "whoosh" all the penetrating oil disappeared down the hole.

The tensioner was free after that. I pumped the tensioner up and then decompressed it twice and was finally able to force grease into that back fitting too on the second run. It slides real easy now.

Obviously that back seal is gone so I guess I just have to remember to shoot grease in there every time I walk past.

Digitup, I like the sound of that super-greaser contraption. A friend recommended getting a K-D Ramo-Matic which is a little tool you fill with grease and whack with a hammer on the zerk, but I like your idea better

[tjdub]

There is a ball bearing under the bleed off bolt with out that it won't take grease .

Mine doesn't have a ball in there. It has a specialty set screw with a square head and a tapered down flat surface on the end. There's no second nut on the set screw like is shown on the parts schematic either. I don't know if it had a ball in there originally, but there sure wasn't one in there anymore. It doesn't leak out of the bleed hole when that set screw is torqued tight so I guess if there is supposed to be one it's not all that necessary.