Happy New 955L Owner With Questions

[Spyros33]

I did that job recently and i suggest that you lay the bucket flat on the ground, remove the Rod pin, start the machine and retract the piston all the way in the cylinder. Then remove hydraulic lines, unscrew the four bolts, drain oil and remove piston. That way you wont have any oil behind the piston that will splash out when you remove it.
Hope that makes sence

 

[leadfarmer]

Great tip! Thanks!

 

[leadfarmer]

On the tilt cylinder see a cast number on the head that holds the outer rod seal of 6J8738 I think. Also looks to have a casting of “MUNRKA” but its hard to read. I dont see any tags attached to the cylinder.

There should be a seal kit, but to get the part number with certainty does the barrel of the cylinder have a spot-welded metal tag on it stamped with a Part Number.?

 

[Nige]

I think your "6J8738" is actually 6J9739. Sometimes it's difficult to distinguish 8s and 9s on something cast, especially if the numbers aren't that big.
"MUNRKA" is the Date Code for when it was manufactured - 21/05/76.

I reckon it is likely that your tilt cylinder is a 7J-9638 Group. Attached the Parts breakdown listed for your machine that shows Change Levels 0-4. For that cylinder the Seal kit is a 243-0384.

However - and this is a reason I think you it might pay you to disassemble the cylinder before ordering parts - from Change 5 upwards on the 7J-9638 Cylinder the seal kit Part Number changes to a 242-2542. The difference between the two kits is the wear ring on the piston. 4J-4630 in the earlier cylinder and 4J-3420 on the later one. So if that cylinder of yours has ever had a piston change to the later part number (the piston part number changes as well) then a seal kit to fit an early cylinder is going to be incorrect.

 

[leadfarmer]

Sounds like I will pull it apart and check the piston number before ordering parts. Thanks for the awesome info. I have spent a lot of time on jeep, chevy, gun, atv, etc. forums, and I think some of the best technical responses I have seen are on this forum.

 

[Nige]

After having slept on it, here's an idea.........
Buy one of the kits plus the wear ring for the other piston option separately. That way when you pull the cylinder down you'll have the piston wear rings for whichever one it has in it. According to the prices in Cat Parts Store it appears as though it doesn't make much difference what combination you pick.

243-0384 Kit - $134.36 + 4J-3420 Wear Ring - $36.60
242-2542 Kit - $141.84 + 4J-4630 Wear Ring - $27.57

You don't have to buy parts from Cat. Offroad Equipment in Alcoa TN, could possibly do you keener prices.

 

[avanfarm]

After reading through this project and gleaning info, I want to say “Thanks”. Nige, with specs and procedures at hand, deserves more than a “thank you”. As my grandfather used to say on occasion, “I thank you ‘till you’re better paid.” To all that take the time to share information, experience, and advice related to keeping these seasoned machines going, you are appreciated! I see many chime in, get info, and bail. Never a conclusion, thanks, or acknowledgement to those that took the time providing the valuable help (leadfarmer, this isn’t directed at you by any means). It surely isn’t the cost of council that prevents a deserving thanks. I get it, everyone’s busy with a never ending list of projects, jobs, or honey do's, but recognizing the help along the way is underperformed. We live in interesting times and technology has its pros and cons. This site and its contributors are etched in the “pro” data column in my book. Thanks again-
AV

 

[leadfarmer]

I sure like say thanks and to close the loop on problems for future readers. I hate when I find a thread with relevant info to my issues and there is no resolution from the original poster.

I finished changing the thermostat in my 955L and I mounted a tool box under the bed of my dump truck, but still haven't taken time to tackle the tilt cylinder due to the weather being either too nice to turn wrenches (burned a lot of brush lately) or too unappealing to venture outside (trim work inside the house has progressed slowly).

I have two weeks to work from home starting next week and I plan on tackling the cylinder then.

 

[leadfarmer]

It’s me again!

Between weather and home renovation projects I haven’t been working on the crawler but tonight I pulled the cylinder apart.

The wide end seal is marked 4J4630. 243-0384 is the kit I need, right?

 

[Nige]

It’s me again!

Between weather and home renovation projects I haven’t been working on the crawler but tonight I pulled the cylinder apart.

The wide end seal is marked 4J4630. 243-0384 is the kit I need, right?

Yes indeedy. Breakdown of kit as shown below. Kit Part Number is still good, i.e. it has not been replaced with a newer P/N.

 

[leadfarmer]

Thanks!

Some pictures of the cylinder. And the 40x60x12 the Amish are building right now for the girlfriend’s horses.

 

[Cat977]

Thanks for posting pictures!

 

[leadfarmer]

Ruh roh.

Kit came with a wear ring 8T5668 that I have no use for and I need another 9X7264 unless the current norm is to assemble the cylinder with only one? This seal is called out as 5J5020 on group 7J9638.

 

[Cat977]

Since you have 2 groves and your not having the cylinders honed. For sure put the second one in unless there's a real good reason not to. You might of just gotten a shorted kit.

 

[leadfarmer]

The kit has a list of parts and it is accurate, only one provided. Odd! Guess I won’t be getting this done till Monday or Tuesday.

 

[Nige]

I think I know why.............

from Change 00 to Change 04 of the 7J-9638 cylinder assembly, two 5J-5020 seals were used on a 5J-6202 piston.
From Change 05 onwards, the piston changed to 3G-3263 and only one 5J-5020 seal was used. See illustrations below.
I guess you could go with one piston seal if you want to - let's face it the later design of cylinders did. Whether you do or not is up to you.

 

[Cat977]

I think that two would keep the piston supported better. Also would help stop fluid from going from high pressure side to low psi side.

 

[Nige]

I think that two would keep the piston supported better.

Isn't support of the piston the function of the wear ring..? The piston seal should have nothing to do with it.

 

[Cat977]

You are right. When I heard piston seal I was thinking like car piston ring. If this item is #12 or for the grove next to it and I wasn't in a hurry I would add it. Rock on Nige! You are great to have on this forum!

 

[leadfarmer]

Thanks for the info! I’m not in a rush so I will get the other seal and put it in. Can’t hurt.

When installing the outer double lip wiper seal into the head is there a common alternative to 7M7456 bearing mount compound that I can use? Like green loctite?