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Fuel consumption, CAT vs others?

fastline · 2020-11-18 11:21

Getting a 322C and previous owner is very honest and said they had more machines than needed and letting the cat go because they have PC220s as well and they sip fuel compared to the CAT. That is the first reference I have heard directly comparing fuel use. I realize it can be a factor of what you are doing but this guy does similar work with all machines. I notice CAT, in the same size class, seems to have more rated HP but that does not seem to correlate into faster or stronger. I am just curious what you guys have experienced? I am not sure if this is related to the closed center hydro system of the PC220s or if this is purely the engine efficiency. I may also need to examine if fuel use is unusually excessive in the 322. He said one day on a tank is it. That is 138gal!

Replies10
  1. #1heymccall2020-11-18 13:31

    Cat excavators, in my experience, are typically designed for an average 10 hour shift. If we're hammering or steady loading, they'll still make 8 hours, normally. I had to Google 322C fuel capacity, as my 322B machines had only a 90 gallon tank.

  2. #2Nige2020-11-18 13:50

    Someone's telling porkies. The O&M Manual for your HEK-prefix machine quotes the fuel tank capacity as 400 litres/106 US gallons. I wonder if someone was helping themselves to a few gallons of free fuel on a daily basis.....??

  3. #3Volvomad2020-11-18 18:43

    Thats great . You have already saved your self 32 gallons a day before you even fire it up . I would have tought 10 gallons /hour should run a 345

  4. #4John C.2020-11-18 19:04

    The Komatsu is fully load sensing while the C model Cats are programed output until the throttle dial is put in position 10. Then it becomes load sensing sort of. The properly tuned Cat uses more fuel but has better feel. That seems like way too much fuel to use on that size machine to me. I would ask if the engine is smoking, how are the air filters, is the waste gate on the turbo stuck, how long since the machine got new injectors? Do you have any fault codes on the monitor? You might do an engine oil sample looking for some fuel dilution.

  5. #5fastline2020-11-19 01:22

    John, as usual, you are on point! I now own the turd...lol When he said "it uses more fuel" I just went with what he said, not beat on all the specifics. I was just curious if anyone else has confirmed that Cat uses more fuel? Well, I really should go further because "using more fuel" means very little to me. Being in the engineering biz, I do realize efficiency is what we are really talking about, or should be. Tons/gallon, yds/gallon, etc. I know it can be difficult to quantify! As to the actual machine, I am an engine guy and so far I have zero concerns with injectors and highly doubt the engine is weak. Zero blowby, no white smoke even at start up, no odd smells or noises. Possible the owner was just exaggerating a bit. t does sound like Cats may use more when not working too hard, but tend to be more 'efficient' when actually slamming bucket fulls. So far, to be honest, I do like the Komatsu feel and controls better, but the Cat is well within the smooth range and sort of splitting hairs. I think I am just sold on the electric over hydraulic which will become the norm, but I know this cat will be a bit more reliable without the extra electronics!

  6. #6Jam2020-11-19 16:52

    If you have access to cat ET you can check the fuel totals. I have a 320dl with the a C6.4 (Mitsubishi) and in 12660 hours it has burned 177463litres. It works out at around 14l per hour which for the output I think is very respectable.

  7. #7Nige2020-11-20 08:35

    That's a calculated as opposed to a measured number. How does it compare with how many litres of fuel actually got poured into the tank, or don't you keep count.?

  8. #8John C.2020-11-20 10:18

    I was commenting on the only one day on a tank of fuel part of your post. Most people I have questioned on fuel usage, comment on only running on between 50 and 70 gallons a day on that size of machine. I can see maybe I misinterpreted your statement assuming in my head that your machine was using a whole tank of fuel. Over 13 gallons an hour would in my mind be exponentially excessive. I can see that maybe I should have taken it to mean if you try to go two days on one tank of fuel, the machine won't make it that long.

  9. #9Jam2020-11-20 16:12

    I don’t keep track of what gets burned to be honest. I wonder how accurate it might be?

  10. #10Nige2020-11-20 16:23

    From my experience it's within 5% or less of the true consumption numbers. The more hours on the machine the more accurate the calculation.