Cat 977H (SN 53A5555) - Not shifting right away. Unsure what to do with old gal

Greetings,

It has been around 6 months but I finally got out to take a look at the old 977H to see if we could get her transported to my property. She is currently parked at the mechanic's shop and after talking to him, I decided that it's probably not a good idea to throw $5K or more at a brake job, when we will likely find more costly issues once she is opened up. So! the plan was for me to have it hauled to my property where I could take my time and try to do a brake job myself. When I got there today, she fired right up after sitting for 6 months. This got me excited, but things went south from there. When I shifted her into reverse she just sat there and didn't shift. I revved the engine up and after about 15 seconds it slowly started to move and then fully moved. Same thing in forward. The last time worked on it, I changed all trans filters and put new oil in it. The transmission and bevel oil level was still good. Any ideas what could be wrong?

I paid $3K for it and with the brake issues and shifting issues, I am in the unfortunate position of needing to decide to cut my losses and see if I can find a buyer for it as-is. I would really hate to see it go, and even worse I would hate to see it scrapped. Someone put a newer D333C in it at some point and the engine seems to be in great condition. 

What would you guys do?

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Did you clean the screen in the bottom of the transmission?
Bob

[quote="bluox post=256928 userid=2232"]Did you clean the screen in the bottom of the transmission?
Bob[/quote]
Hi Bob, unfortunately, no I didn't clean that screen. Both places where I have worked on it previously were not my property and I didn't have much time or ability to dispose of old oil. I did drain the bevel housing into tubs and transferred that to 5 gal buckets but I didn't have enough capacity to drain the trans as well. Also, the trans lube looked really clean, so I concentrated my efforts on the stuff I could easily get to, like filters. If I'm not mistaken, cleaning the trans pickup screen requires completely draining the trans, correct? It does feel like something is clogged up to me and not getting the proper flow. It's behaving much like a 977K that I looked at recently. That machine was acting the same way and after I replaced the filters it shifted and moved just fine. Given that I have replaced all of the other filters, do you think that just the screen could be causing the issue I described? If so, this does give me some hope for the rest of the machine. I think I could eventually get a brake job done on my own. I don't have a shop yet but I have other machinery that I could use to lift the heavy parts that need to come off in order to do the job.

Any feedback on this situation is greatly appreciated. Thank you!