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Recent content by Aaron.Phillips07

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    1971 CAT 977L Coolant in Hydraulic Oil

    Very heavy winds today. I wasn't able to attack this outside but will update tomorrow if the wind calms down. In the meantime, I have found quite a few places that make OEM replacement parts for the 8N-4914 part number and they all have separate compartments for oil/coolant. At least from what I...
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    1971 CAT 977L Coolant in Hydraulic Oil

    I'm going to be working this afternoon/evening to remove the oil cooler and 100% verify that it does in fact have an oil AND coolant line(s) running in and out of it. Have you guys ever seen something like this before? The manual and parts book in this sense have been very hard to figure out...
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    1971 CAT 977L Coolant in Hydraulic Oil

    I completely agree with you Nige. This has been a bit of an odd issue. My brother was able to clean away some of the old gunk around this part of the system last evening and found the part number: 8N4914 on the cooler. Date stamp of 6/79. This machine worked in a rock quarry most its life and...
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    1971 CAT 977L Coolant in Hydraulic Oil

    Here's what happened two times in a row identically. I changed out Hydro fluid and filters-->topped off radiator coolant-->warmed machine and cycled through bucket movements slowly to circulate new fluids-->ran for 1.5 hours. - After each of the two times, I was exactly two gallons low on...
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    1971 CAT 977L Coolant in Hydraulic Oil

    The oil cooler is next to the coolant radiator. It is about 10” wide and the same height as the radiator, same material and design. Just a smaller skinnier version.
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    1971 CAT 977L Coolant in Hydraulic Oil

    Good evening. I have a 1971 CAT 977L with a D333C. (Serial 70J1348). When I purchased this machine, it had very milky fluid and I have since flushed the system out twice with cheap Tractor Supply fluid, new filters for each flush, but somehow keep ending up with (what I thought to be water) in...
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    Identifying CAT 977 (K or L) help

    It's been a BUSY month but I've been able to do fluid and filter changes, get about 4 hours of heavy run time on this.......it's a BEAST. This engine runs extremely well, shifts smooth, steers smooth, and I am very pleased with the condition this machine is in. Such a huge blessing to my family...
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    Identifying CAT 977 (K or L) help

    I have an interesting update I believe. I finally got another chance to do some cleaning on the engine block and found the block serial number. I got everything cleaned up and it is very easily visible. Attached is the picture of the markings as you see them on the right hand side of the engine...
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    Identifying CAT 977 (K or L) help

    Gentlemen, I can’t thank you enough for your help. I’m sure I will have something pop up here and there that I might need help with. Thank you for being so kind helpful to me.
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    Identifying CAT 977 (K or L) help

    Thank you, Simon! Attached are the photos of the service manuals that came with our machine.
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    Identifying CAT 977 (K or L) help

    I’m actually heading back outside for a while to finish working on changing out hydraulic fluid and picking away at some other things. If you need better or different pictures, please let me know!
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    Identifying CAT 977 (K or L) help

    I am so pleased with these responses, thank you very much everyone for being so kind and offering your help! * Please see attached photos of the fuel system. I could be wrong as I’m still learning. * As for the undercarriage, yes you are correct. I didn’t share any details, sorry about that...
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    Identifying CAT 977 (K or L) help

    Hey guys. I am new to owning a CAT 977 although I have operated other heavy equipment for many years. I recently purchased what I believe to be a 977L model (Serial # 70J1348) and found that during a production run in 1971, they started making the L-model but kept the K-model serial prefix 70J...
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