I've just had the occasion to repair a leak on the blade tilt cylinder on my D21. I bought a seal kit and proper size hook spanner. However, the design of the slots on the cylinder end cap was such that the wrench would slip out of the slot because of the taper bottom of the slots. I stopped before I caused any damage and took the cylinder to a professional shop and let them replace the seals. I was wondering if there is a special design spanner wrench for these Komatsu cylinders?
Big pipe wrench or a chain wrench is all I ever used on them.
Yep, 48" pipe wrench does wonders
Those caps are usually too tight for the hook spanner to do anything. Air hammer and flat bit will often move them, pipe wrench, chain wrench (aggravating) are other options. While putting tension on them with the wrench smack the hell out of the area just behind the cap with a hammer...this is the area where the gland assy is threaded into the barrel. If that fails then you have to heat them. Also always check for setscrews.
I had the same issue with mine as the other post stated I used a 36in pipe wrench and made sure it was good and snugand used a sledge to hit on the back side of wrench up close , you could put a cheater pipe on the end of pipe wrench but what happens is that those cylinders are made of aluminum and will start gouging pretty good before it breaks loose, I did all mine about a month ago, the smaller cylinders they make a tool to put the inner seal in and its worth getting about $30.00 and you get alll 3 sizes. I made a post on this on my section in the komatsu d20 d21s, just make sure you load that head up with grease this way the seal wont ride up when your putting it back together, don't be surprised if you run across some water in there that's the lowest part so water might be in there maybe 3 or 4oz at the most
once you hit the pipe wrench 2 or 3 times then try tugging with your hands all it takes is for it break loose a 1/4in and after that its comeing off oh going to be a good amount of oil coming out so I would raise blade then put some blocks undneath to hold it up then a bucket or big catch pan and you don't have to take the whole thing off just that one pin leave the other one attached there is also some rubber gromets or isolators not sure the correct name mine were in really good shape, need anything else shoot me a message have a great weekend
What hyd. cylinders are aluminum?
Heads.... not the tube
What's the advantage of an aluminum head on a steel cylinder?
Cheaper, easier to machine.
well im not 100& sure but on the Komatsu d20 their aluminum the heads are
On a dozer it doesn't make sense to me. Steel isn't hard to machine and should be cheaper than aluminum.
You get to sell a whole new ram when the aluminium head cold welds itself to the steel barrel.
I was thinking about galvanic corrosion.
Corrosion may play a part in the welding. Aluminum just doesn't like to be threaded like that, seems like steel bolts in cast aluminum is OK, but threaded alloy parts just like to gall and seize. I guess you're right about aluminum being more expensive than steel, but I still say the aluminum has to be much cheaper to machine, why else would they use it?
Would be interesting to know.
Cylinders are bought on bid by local contractors usually. Low bid gets to use whatever material they see fit.
Aluminum can be used as a direct bearing surface
I guess it would save having to need a wear ring.
I took my cylinder to a local shop where they had the proper tools to remove the end cap. The end result was no damage and a professional job overall. There is never a substitute for the proper tools for a professional job!