Case 550 Dozer Track Wear Measurement - Problem Working Sidehills

[Blueacre]

I have a Case 550 Long Track Crawler Dozer. It is the original model of the 550 manufactured from 1989 to 1991. They changed to the 550E starting in 1992 but I am not sure if the 550E had the same track specs.

The track and drive sprockets looks in fairly good shape and works great on flat ground but when I work on a faily steep sidehill the drive sprocket teeth start to climb up on the side of the rail (chain) until the track tightens up so much that it jams. I have to reverse a little to let the sprocket teeth settle back in the rail and then I can go forward again.

I want to measure the undercarriage wear to see if that is contributing to the problem but I cant seem to find the specs any where for the Case 550. Need to know what the new measurements are and what are the acceptable wear limits at say 50%, 75% or 100% wear. Looking for all the wear dimensions including rail (chain) pitch, rail height from bottom to underside of track pad, Rail bushing diameter, top idler roller diameter, bottom track roller diameter, drive sprocket diameter over teeth.

Not sure if these dimensions are in the service manual - I dont have one for this machine. Appreciate if anyone has this info for a Case 550 dozer and could let me know.

 

[Bls repair]

Photos of undercarriage near and far would help.

 

[Blueacre]

I found a digital copy of the Case 550 Dozer Service Manual online for $20 so I purchased it. Has all the info for measuring the track chain, rollers and front idler wear and tables that show the percent of wear based on the measured dimensions. Havent found anything yet on how to measure the wear on the drive sprocket other than looking at the ends of the sprocket teeth - they tend to wear to a sharp point when badly worn rather than a rounded end. I have an operators manual for a case 450 crawler tractor I used to own and it shows using a track gauge, Case part number D36767, that has a template for the drive sprocket teeth to show how much wear they have.

 

[Bls repair]

How is track tension?

 

[Blueacre]

I try to keep it at 1 to 1-1/2 inches of sag in the track between the top roller and front idler as recommended in the manual.

 

[Tones]

Do the track chains have letters and numbers cast on the links probably just below the grouser? If so that is a good reference to find the chain pitch then measure the pin centres. From that info you can determine the wear.

 

[John C.]

If it is SALT track you generally won't find a pitch measurement. Basically the only way it would stretch is if you have dry links and in that case you have some fixing to do.

 

[Bill Edwards]

Does your manual tell you how to measure internal pin wear - that's what I'd be looking at to see if it's allowing the track to snake sideways.

 

[Blueacre]

I had a look for letters and numbers on the chain but didnt see anything obvious - will have to clean them up better and see. Manual shows both a Sealed track link and a Case lubricated track link were available for this machine with either a 6.0 or 6.29 inch pitch.

Not sure how to tell the difference between sealed and lubricated tracks ? Is there an obvious difference from the outside. The manual shows the Case lubricated track had 2 inch diameter bushings when new and the Sealed Track had 1.85 inch bushings - Mine look like they were 1.85 new so I am assuming I have a sealed track.

My pitch measures about 6.1 inch on several links so I assumed it is a Sealed Track Link. I took some measurements on one track - measuring over 4 links (ctc 5 pins) I get 24.3 inches - service manual shows that as 66% wear for a sealed track with 6 inch pitch. Bushing measured 1.75 inch minimum diameter in forward and reverse positions which shows as 82% wear for low impact conditions, 94% for high impact conditions. Vertical bushing measurement is 2.5 inch which is 29% for low impact and 39% for high impact. Track link height is 3.28 inch which is 67% wear. Top idler roller measures 5.25 inches which is 63% wear - no flat spots. Track rollers measure about 5.74 diameter on the front and rear - 63% wear and 5.83 on the center 3 which is 49% wear. Front idler measures 0.73 which shows as 16% wear. Not sure about drive sprocket wear but it is still about 1/4 inch wide art the tip of the tooth with a smooth radius - not worn to a sharp point like I have seen on other machines.

I only use this machine 50 to 100 hours on the farm. It is in good condition, starts and runs great, 6 way blade is fairly tight . From the measurements bushing wear and chain pitch stretch show the most wear but not sure if it is worth spending the money on new chains for the amount I use it. The track never slips on the sprocket when running with the recommended track tension - only problem I have is the sprocket climbing the chain on steep sidehills and I probably dont do enough sidehill work to justify about $4000 for new chains, sprockets and pad bolts including labor to remove and replace pads just for that.

Not sure if turning pins and bushings is an economical option ?

 

[Tinkerer]

Does the machine have the (any) track guards on it ?

 

[Bill Edwards]

Lubricated tracks (at least the ones I've seen) have what looks a bit like a grease nipple in the pin centre that they use for putting the oil in. Check the inner side of the link as well as the outside, but I'm pretty sure from your description that they're dry and pretty much worn out.

As to what to do about it if they're worn too much, that's tricky.

 

[Blueacre]

Does the machine have the (any) track guards on it ?

No rock guards on it.

 

[Tones]

3 types of track chain, dry bush- no lubrication, lubricated-grease, SALT, oil lubricated. A lubricated chain is greased at assembly and that's it for it's life