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Help identifying 955L

Delinquent26 · 2023-12-12 00:15

Hello all. I'm looking to restore an older Cat 955. Can some one help me identify this machine. Cat 85J875x Engine 3304 78P -I want to rebuild lift/tilt cylinders. -Put original length hoses on lift/tilt cylinders -Change hoses on 4-1 bucket But I can’t find any info

Replies29
  1. #1tctractors2023-12-12 15:30

    Looks like a 955K to me

  2. #2AllDodge2023-12-12 16:07

    Mines a 85J5044 and came out with the older motor (330 something I think) and was in the change over process from K to L. With yours coming with the 3304 and if it's original then I'm thinking L Nige will know

  3. #3Nige2023-12-12 19:15

    All the information given below is on the basis that the machine S/N given is correct and that it has the original engine. According to Serial Number it's a 955L. The L model replaced the K from 85J4672 but continued with the D300-series engine. The 955L was fitted with a 3304 engine of 78P prefix from 85J6247 onwards. 85J875x would make it a fairly late 955L. IIRC 85J Serial Numbers went up to somewhere 10,000 or so. As regards putting a year of manufacture on the machine I can't help. I'm sure either @OzDozer or @Old Magnet will have the info.

  4. #4Delinquent262023-12-13 00:45

    Thanks for confirming that. I stopped by Cat for help with finding Lift/tilt rebuild kits, and they said it’s K model. The Tech couldn’t find model K or L Cylinder kits, but he did find all the individual seals to make up to the kit. Now the problem I’m running into is, the individual seals don’t list my tilt/lift cylinder numbers as being compatible. So they want me to bring The cylinder piston in

  5. #5AllDodge2023-12-13 07:47

    While Cat will do a great job, you can get it done cheaper at a local hydraulic shop.

  6. #6Nige2023-12-13 10:06

    That’s because in the latest version of Cat's online Service Information System (SIS 2.0) that's what it tells them. See the snip below. However.............. All is not as it seems unless you speak to someone who has experience going back to the time prior to SIS 2.0 being introduced and can recall the former system, known today as "legacy SIS" or "SIS 1.0". In that former version if I put the complete Serial Number into the box it would pop up straight away as a 955L. If I was to put simply 85J into the box it would offer me the list of options shown below that support my assertion that your machine is actually a 955L Click on the hyperlink for the range of Serial Numbers on the second to last line (which includes yours) and the head of the SIS page would change to "955L Traxcavator". I have come across this in SIS 2.0 on other models where the model suffix changed during the production run, as in this case from K to L. Because production started with the K model SIS 2.0 calls any 85J Serial Number a K, despite the fact it might be an L. It's an issue with SIS 2.0 that has so far not been addressed by the Caterpillar IT germs. I hope that clears that up. This has been a public service announcement.

  7. #7Nige2023-12-13 10:46

    OK, on to this one. It appears as though they didn't dig very deeply. IMHO the best way to definitively identify your cylinders is to find a metal tag on them that will show the Part Number, and the Change Level, of the Cylinder Group - the complete cylinder in other words. For the Serial Number range of machines 85J6247-9509 the following possibilities exist: - LH Tilt - 7K-9443 or 7J-9638 (5.0" bore x 23.0" stroke) RH Tilt - 7K-9444 or 7J-9637 As far as seals go each pair of the two above Part Numbers are identical. The difference is in the cylinder barrel (LH vs RH). However - the seals are different between a 7K-9443/7K-9444 and a 7J-9637/7J-9638. To muddy the waters even more there were various iterations of each Part Number produced and the seals change within those iterations. e.g. for a 7J-9637 from CHG00 to 04 the seal kit is a 243-0384, from CHG05-Up it is a 242-2542. You can see how easily this can become a minefield...... Lift Cylinders - 7K-9380 or 7J-9640 (5.5" bore x 32.77" stroke) For a 7J-9640 Cylinder Gp the seal kit is a 243-0383, there is no kit that I can find for a 7K-9380.

  8. #8OzDozer2023-12-13 19:52

    There's plenty of aftermarket seal kits for these older Cats, and a Bulldog seal kit would almost certainly be available for your cylinders. Nige has nailed it, the cylinder part number is where you ID what particular cylinder you have and what seals it takes. There are multitudes of hydraulic cylinder part numbers. Cat 955K & 955L Loader Lift Cylinder Seal Kit See our Cat 955K & 955L Loader Lift Cylinder - Seal Kit, now online. See more. hwpartstore.com Bulldog | Quality Aftermarket Replacement Parts for Heavy Equipment - Demand The Brand. Bulldog is the premiere provider of sealing solutions for heavy equipment worldwide, offering hydraulic cylinder kits, engine gasket kits, transmission seal and gasket kits, and assortment kits. www.bulldogkits.com I'm presuming the "X" suffix is part of the serial number, and not just added by you, as a number at the end of the serial number, that can't be identified. The "X" suffix is superflous in Cat parts and serial numbers. It's used as an identifier within the Cat system that refers to the factory where the item was produced, and is ignored when used in the parts or serial number systems. Your tractor serial number is defined on computerised systems as 85J0875. If that's correct, this means your traxcavator is an early 955K, built in 1968 (the first year of production) in the U.S. If the serial number is 85J875X, with "X" being a number between 0 and 9, then it would be a 1974 year of build, and it's a 955L. What is curious is you state the engine has a 78P engine prefix. The 78P prefix identifies the engine as a 3304 model, and this corresponds with a 1974 year of build. If your tractor is a 1968 model 955K, it would have been originally powered by a D330 engine with an engine serial number that is the same as the tractor.

  9. #9Delinquent262023-12-13 20:02

    Thanks Nige, you’re the best. I’ll look closer at the cylinders. I don’t remember seeing a tag, assuming its in an obvious location. ..if no tag, Ill take it to Cat this one time, and get the numbers they use to rebuild it.

  10. #10OzDozer2023-12-13 20:11

    The cylinder part number is often letter-stamped into the older cylinders. Sometimes you need to clean off the paint to see it clearly.

  11. #11Nige2023-12-13 20:25

    The OP originally sent me a PM asking for help in which he quoted the complete machine Serial Number. The "X" in his first post corresponds to the last digit, a number between 0 and 9. He obviously does not feel comfortable posting the complete S/N. I respect that and will refrain from posting it. Look anywhere from right next to the head end of the cylinder barrel to about 6-9" away from the head/barrel joint. As @OzDozer pointed out it may be a stamped Part Number rather than a tag.

  12. #12Nige2023-12-13 20:36

    If you can spare the time to tear down one cylinder then from photos of the seals that are in it the cylinder Part Number can be identified. The best part about the cylinder Part Numbers I mentioned above is that to someone who knows what he's looking at the differences between the various Part Numbers (and CHG Levels) ought to be obvious.

  13. #13Delinquent262023-12-13 22:34

    That’s it 1974, wow I don’t no why but I just had to no. Thanks OzDozer I came across Bulldog in my search. At the time, I thought the number stamped on the cylinder was the cylinder number.(photo) and it didn’t match up with bulldogs seals Nige said look for a tag, so tomorrow I’ll double check all 4 cylinders again

  14. #14Nige2023-12-13 23:01

    That’s a casting number. The cylinder number, whether stamped or in a plate, will be much less obvious.

  15. #15OzDozer2023-12-14 00:45

    The number showing in your last photo is a casting number, as Nige says. Most times this number is the actual part number of the casting, other times it's a number that is not recognised as an available part, because it's only available as the entire component to which its attached. The Cat NPR (Numerical Parts Record) on the original microfiche tells us the name of the item, and whether the number is/was available as a part, or whether it's part of an "assembly" or "group". The NPR also tells us precisely what machines/serial numbers the part number fits, and whether it was upgraded or replaced by another part number. I guess the current Cat SIS system has this information available as well, but I have no experience of the current Cat SIS system, I'm just an old microfiche, paper, and books dinosaur. I would imagine the SIS system has no information on anything before about 1970.

  16. #16Nige2023-12-14 20:53

    Is the Part Number on the photo of that casting 6J2635 or 6J2636.? The last digit is not visible.

  17. #17Kevin Hayes2023-12-15 13:14

    K's and L's look the same. The earlier H models have a slanted hood.

  18. #18tctractors2023-12-15 15:34

    No they don't look the same, lots of changes from an L to a K Series.

  19. #19Nige2023-12-16 09:02

    You never mentioned whether or not you had any manuals. For your Serial Number the Parts Manual is Caterpillar Publication UEG0700S. Here's one on eBay For the Maintenance Manual you need SEBU6520. You can download a pdf version for $30 from HERE . Just put SEBU6520 in the box and click search.

  20. #20PhilDirt2023-12-16 15:26

    Here's the parts list from doing cylinders on my 955L 2 years ago. I had aftermarket seal kits on hand, the seals were too small to fit my cylinders so the mechanic matched them up at a local hydraulic shop. I hope these PNs can be crossed to something available to you. This was for 2 tilt cylinders and one lift cylinder. The machine is SN 85J4799, it was delivered in January 1972 so I assume it was built in 1971. The cylinders have no numbers stamped on them. I looked hard, and the mechanic who is very Cat knowledgeable could not find any either. Hope this helps.

  21. #21Nige2023-12-16 16:10

    For Tilt Cylinders the piston Part Number changed during the production run of the 7J-9637/7J-9638 cylinders. Early (CHG00-CHG04) cylinders had two 5J5020 Seals (Ref #12) on the piston. Later (CHG05-Up) had only one. The fibre wear ring (Ref #14) on the piston became longer on the later piston with only one seal. The wear ring Part Number changed from 4J4630 (early) to 4J3420 (later) Apart from that all the other Tilt Cylinder seals are the same. The one thing I am unable to do is to accurately date the change from the Early to the Late piston design. EARLY 7J-9638 TILT CYLINDER GROUP - CHANGE 4 - 5.00" BORE X 23.30" STROKE LATE 7J-9638 TILT CYLINDER GROUP - CHANGE 5 - 5.00" BORE X 23.30" STROKE

  22. #22Nige2023-12-16 16:23

    Here is the list of seals for early/late Tilt Cylinders. I have updated Part Numbers to the latest P/Ns that are currently available. Common 1 x 2K4096 Ring, Backup 1 x 5F3144 Seal, O-ring 1 x 1672312 Seal, U-Cup 1 x 1672201 Seal, Buffer 1 x 1672463 Seal, Wiper Early piston 2 x 5J5020 Seal As 1 x 4J4630 Ring, Wear Later Piston 1 x 5J5020 Seal As 1 x 4J3420 Ring, Wear

  23. #23Delinquent262023-12-16 21:52

    Thanks PhilDirt. That will probably come in handy. Nige the number was 6J2635. When I looked it up, it came back as a cylinder Lug. I have that parts manual, but my maintenance manual is GEG0983-02 I Finally got out to look again. Here’s a look a what I found. Something stamped on bottom flanges

  24. #24Delinquent262023-12-16 21:53

    Thanks PhilDirt. That will probably come in handy. Nige I Finally got out to look again. Here’s a look a what I found. Something stamped on bottom flanges

  25. #25Delinquent262023-12-16 21:55

    Are these bands what you refer to as a tag? Not legible

  26. #26OzDozer2023-12-16 22:31

    The bottom flange numbers are casting numbers, not stamped letter markings. You need to look for indented letter stamp, numbers/letters. The bands in photo 2 and photo 3 above are the bands Nige was referring to, showing the part number of the hose and the pipe respectively. If the pipe is welded to the cylinder, it may be the cylinder part number band.

  27. #27Nige2023-12-16 22:54

    That confirms your Tilt Cylinder Part Numbers as 7J-9637 & 7J-9638.

  28. #28Nige2023-12-17 10:41

    Because that tube bolts on to the cylinder the tag will have the P/N of the Tube on it, not the cylinder.

  29. #29Nige2023-12-18 14:44

    OK, so as far as I can determine your Lift Cylinders are 7K-9380. The seals are: - Head 1 x 1757905 Seal, O-Ring 1 x 2K2961 Ring, Backup 1 x 1672201 Seal, Buffer 1 x 7J4824 Seal, U-Cup 1 x 1672463 Seal, Wiper Piston 1 x 5J4988 Seal As 1 x 7J1731 Ring, Wear