Hi all Got another question if anyone can give me some input.. Looking at buying a 977L ,i believe it is a 1978 model,it seems to lack a bit of power in my opinion.Starts ok ,no obvious smoke from the exhaust.We were running iyt up and i got the owner to drive it as i thought it best at the time.I got him to push a load of dirt out of teh way,it would have equated to half a bucket and i am not sure if he had it in low gear or not but it seemed to struggle a bit,its got me worried taht is may be the compression is down.But i dont know.Wondering if these had injector or turbo problems ? and would tehy have obvious symtoms if it did ..i checked the engine oil and it seemed ok,pretty clean and no water in it.There is no rattling from the topend or rocker noises,it seems quiet.If i had to assume the compression was down can you do an in house rebuild on these things ? what would be involved to change out i assume rings if needed.Not sure what engine it is either,but its a 6 and has a turbo mounted on it..I always assume that low power is usually aisgn of low compression when i dont see a bunch of unburnt fuel spewing out of the exhaust,any helpor advise would be interesting ..thank you
Low compression in a diesel = blue/grey smoke. If it doesn't smoke when running cold at startup it's probably a fuel pump issue causing low power. Bad turbo = black smoke under load.
Check the throttle linkage is okay and you are getting full travel. Later Bob
Hi Mobitech thanks for the information.The muffler is right pretty much in front of the cab to the right side..yah even though i was having a great time in it ,bit kid like..haha i didn't notice black smoke,or blue smoke really,i guess i can rule out a bad turbo and or compression then.So i can assume that worn fuel pump will and can still blow a clean exhaust under load ? i get the feeling this old girl hasn't been regularly serviced much just by looking at it..cheers How common has it been seen that a fuel pump is causing low power out of interest.? Bob , i may have over looked that one ,linkages could be bent ect yeah on this old girl.I didn't notice come to think of it though that it revved high,probably around it mark by the sound of it..worth checking thank you..
Grizly have someone hold the throttle open then push on the lever on the governor and listen for an increase in revs. Need to take RH side cover off for this. Later Bob
Yeah for sure check throttle linkage for full travel first. The next thing would be fuel pressure. When you say low power do you mean it lugged down too low or was it that it just didn't move the pile very easy.
Mobiltech, We started to push into the pile pretty much and the more it got the slower it went until it just laboured,it just didn't move the pile of gravels and dirt very easily..The pile was half the height of the bucket really,and we had traveled only around 3 meters into it,it just struggled from there on after having half a full bucket at most..I would expect to see it push its way through that small of a job easily with hesitation like a dozer around the same HP would do.This was all loose stuff that had been previously dumped.It pulls into a dam wall ok and then everything falls into the bucket and loads itself.
What is the serial number, is it 11K(71-77) or 14X(78-83). Questions: 1) Did you check the transmission and torque convertor pressures? 2) Did you check all the fluid levels? 3) When were the fuel filters last changed? Before disassembling the engine or anything else do the diagnostics, if you don't have the tools call your Cat dealer, his charges are cheap compaired to rebuilding drivetrain components one at a time. I own a 977-L 14X2022 and it pushes through a 15 CY. tandem dumptruck load of dirt like it is feathers.
I think you need to have someone look at it and check rpm under full load and torque stall speed to see how far off it is . It could be engine or torque converter problem but without checking it against cat specs you have no place to start troubleshooting. I don't think you would have to tear the engine down for any of this if it doesn't have excess blowby or smoke a lot .
most all 977L's were the 3306,good engine.early engines were PC,the later ones were DI..all turbo'd.some of the early 977Ks were the D330,but not much difference...make sure you were pushing that pile in 1st gear,even with a good machine she'll slow down in 2nd/3rd unless WOT..