I'm doing a reseal on a cat 303.5 mini excavator final drive motor. The toric ring is extremely tight to go in. With two people using the wire between the faceplate and toric ring to press it in we are unable to get it to seat in. If trying the method of working the toric ring in using a blunt screwdriver etc. at the end there is a little U sticking out and I'm not able to get the o-ring to seat in completely. Any ideas? Might have to pony up and get the tool or drop it off at CAT and have the pros seat it in...
Lubricate the O-ring with isopropyl alcohol (some call it dry gas for preventing gasoline line freeze up). Use nothing that leave a film.
Good day the attached may be helpful;. Kind regards Uffex
The new toric ring is just too tight on the hydraulic assembly side. The new toric went in how you'd expect it to on the hub side. I tried using the old toric from the hydraulic side and it goes together like the new one did on the hub side. Since it's winter and I have time I'm going to reassemble it like this and monitor for leaks. The toric is seated nice and level and I like how it went in. I'll add some pictures when I can.
Any tips on getting the wire back in? I was thinking put a hook in the wire while turning the cover. I was tapping the cover around with a punch and hammer but it was just straightening the wire. If I can thread into the plug holes with some bolts or something I should be able to turn it while feeding the wire in.
I have had fairly good success using talcum powder on Toric rings.
The only time I've had problems getting toric ring to seat was when I didn't get the lands clean out good. Sometimes they are a bugger.
I haven't done one yet, but I was pondering on them the other day. Is is possible that the wire is in place first, then the cover is pressed on? (pressed until the wire snaps into position)
That might be possible. I already had to tap the cover on so it might be pretty tight. What I did was thread in some fittings to the drain plugs so I could turn the cover. Then make a hook on one end of the wire and get it seated in the hole and rotate the cover while keeping pressure on the wire and it gets dragged into the hole. Keep that up for one rotation. It went in a lot easier than I expected once I figured out the method. This is the way they do it at the factory I think because it has that same hook on the end. I'd be worried about the wire breaking if you pressed it in and you wouldn't know. Should have taken a video. Here's the drive reinstalled, some new track parts, and the tool I fabbed up for the massive bearing nut with slots in it.
Thank you for the document, good to know there may be some oil from the seal while the steel surfaces lubricate. I'll be watching it closely for leaks after putting the machine back to work.
I cleaned, used some fine sand paper, and brass wire wheeled the lands. The new toric ring would not pop in with two people pushing on the ring (with wire between plate and ring). And trying the blunt screwdriver method I could get it all popped in except a little loop at the end almost like either the machining on the hub part was off or the toric was off on size. The old toric cleaned up well, and seemed to be in very similar condition to the new toric. So I cleaned it up and used it and so far not leaking. I have time this winter to tear it down again if need be but this was the only possible option for me at the moment.
Somewhere along the line a bit of advice from mother CAT actually made sense, and I have used this method with great success: Put the metal ring with toric installed on it into the freezer for several hours, overnight if possible. No, no dry ice or liquid nitrogen, damn cast rings are brittle enough as it is. The cold shrinks the diameter and stiffens up the rubber so it slides instead of grabbing. May not be enough for your seal, but usually the literally "pop" right into place. Check for level and allow to warm. If it ain't quite perfect and it doesn't want to adjust, just remove it and refreeze.
Exactly right on the lock wire, you have to put the cover in, then rotate the cover to draw the lock wire in.
I even had it in the freezer for a bit! It just didn't feel right even if I somehow got the new ring in I don't think it would sit right. I'm pretty happy with how it went together and it's currently leak free so we shall see! A good experiment in my mind either way to see if you're able to reuse a toric ring if they leak due to mud/dirt getting packed in the back of them and there's no other issue with the drive.
that wire lock ring method is also used on some small hyd cylinders such as steering cylinders on ag equipment and forklifts, etc. they can be tricky to get apart if there is rust and corrosion involved
It's essentially a static seal, if the toric was clean, soft, and undamaged, there's no need to worry about it until it needs repair for some other reason, or it actually starts to leak again.
Good to know, it was an interesting experience to work with one I'm glad I was able to figure it out. That's what I was thinking as well. I appreciate your input and experiences, looks like you have a cool tractor store selling specialty parts - I just checked out your website.
As a rule of thumb on a machine working 24/7 we would not contemplate doing anything regarding a Duo-Cone seal that was weeping from new or after rebuild until the machine had clocked at least somewhere between 500 & 1000 hours of operation. That would be 1-2 months. Getting the height of both rings consistent all round the circumference +/- as close as you can get to zero is the best way to avoid leakages on Duo-Cones after installation. To measure this height you can use the plastic tool that often comes in the box with a new seal assembly or a vernier depth gauge works just as well.
I've never seen the tool in all the years I've turned wrenches. That is interesting.
You mean the measuring tool I take it.? Most of the big Duo-Cones (789/793/797/994-size) come with one in the box. If I'm not mistaken there are different colours for different height settings. I need to refresh my memory in the Dealer Service Tool Guide.
Oh Nige, you have lived in a different world than most of us commoners, I truly enjoy and deeply envy the storehouse of knowledge and experience you share with us. I'm willing to bet when you cut yourself accidentally that you bleed yellow a bit? One of my biggest regrets in my working life is that I did not come up through one of the major dealer networks, all my jobs were in the "Bush fix" category. I can probably repair a busted planetary with some spare lug nuts and a welder and it would last long enough to get to the end of a project, but "Doing it right" has always seemed tantalizingly out of reach for me. Sadly when I did work at a CAT dealer later on it was in the parts department which being neglected and abused by most everyone else there, I never got to go to Peoria for the blood extraction and yellow transfusion. Cheers.
Good day This site has some informative information. Kind regards Uffex http://www.sealsolutionsaustralia.com.au/product/floating-seals-duo-cone-mechanical-seals/
This is the gauge Nige is referring to. It's been many years since I saw one packaged with a new duo-cone. Part number is 8T0535 but it appears to have been discontinued.
My little duo-cone kit did not come with a gauge but I did confirm uniform height all the way around - with a little pushing and pulling on it.
Had to go back to an old Tool Guide to find them. There were actually five Part Numbers Chris. 8T-0533, 8T-0534, 8T-0535, 8T-0537, & 8T-0540. The last one was the "hook" adjustment tool for raising up a Duo-Cone seal that had been pushed too far into the ramp and was below specified height. All five appear to have gone the way of the dodo in NPR but they are still listed in some final drive/wheel bearing kits like the example below.
I remember that hook tool. I always preferred using an allen key. I just checked 3T9117 in TMI and it looks like the tools are no longer included.