I have a friend with a John Deere 270D excavator that has about 4000 hours on it .Machine no older than two to three years old.It over heats after about ten minute of hard working .Had the dealer out and can not find out why it happens.They took a temp read on the top and bottom of the radiator ten degree differnce.Is that normal ont htis unit.If you let it idle every thing goes back to normal.Unit has a new thermostat,coolant ,cooolent temp sender,fan belt is tight .And radiator and oil cooler are clean on the fins .I told him to llok betwwen the two and double check.It has a hydrualic driven fan.I thought maybe the cores are getting clogged in the radiator slowing the flow down .I asked does it hace coolant filter .He was going to check.Any other thoughts on this .The machine is Washington DC so I can not go and look at it.But would like to see happen to try to figire it out . THANKS ED
I don't believe it has a coolant filter. Could take a look at the fan itself. And check the rubber styerfone that goes around the bottom of the radiator.It some times gets loose and goes in the rad.. Only other thing i can think of is take the cap off the radiator when it is cold and fill, then let it get warm and see if it is circulating in the top of the radiator. If its not it could be the water pump. It does have a high and low thermostat. Try this. Maybe it will help??
Probably a long shot here but had a similar problem with a machine of mine, thing that caught my attention was when you mentioned everything returning to normal after idling for a period of time. In my case it ended up being broken baffles in the muffler, ran VERY quiet, started easy but always got hot no matter what I did to the cooling system. I finally put a pressure gauge on pipe between manifold and muffler and after finding what I considered high back pressure 10psi full rpm no load peg gauge 15 load, I cut a 4"x4" whole in the side of the muffler just be be sure. Again just a long shot.
From my experience working on excavators you need at least fifteen degrees difference between the outlet on the thermostat housing and the inlet on the water pump. Most likely the problem is debris stuck between the hydraulic oil cooler and the radiator. Those machines don't usually have heating problems if the cooler fins are clean.
I had the same problem with my 350D it's the hydraulic fan motor. The original one has aluminum parts in it which wear out the new one will be all steel internals.
Thank you guys for all the info.The operator of the machine is good friend of mine.He is good with problems on machine .But this one is blowing his mind .Even dealer wrenches can not figure it out .He is going to double check between the radiator and the oil cooler .I will talk to to him in the morning. I worked on a old SamSung excavator one time were the foam was missing around the radiator.And did not have enough air flow through the radiator fins. Causing the excavator to over heat.
When I had an identical sounding problem w/ a Cat, it was a crack in the muffler, blowing exhaust through the radiator.
Its most likely the hyd. fan I know of two like 05 or 06 (I wanna say) machines that had this prob, apparently deere was buyin the fan setup from a company and has now switched uur something like that
Update the dealer replace the hydrualic fan moter with the steel one and no more overheating problem.Thank you all for the update with this problem on these machines .
toolking set it on fire and collect insurance money then buy a yanmar excavator you;ll be glad give one a try and you;ll see. had jd and cat before yanmar they are total junk
yanmarman, I understand you are a Yanmar fanboy but, come on already. All you ever do is talk smack about other brands. You seem to only want to troll and get a reaction. If you have nothing constructive to say, its best not to say anything. Oh, use some punctuation and sentence structure and that will help with your credibility.
Well said Lee Online .Yanmar does not even make a machine even close in size to Jd270 which is a Hitachi ex270.Costs way more than any yanmar excavator.
Yanmar does;nt have to build excavators that size,just so much faster ,whoops enough said
:falldownlaugh
Do you have to wear a fighter pilots G-suit when you're running that Yanmar fast enough to keep up with a 63,000 lb hoe? I hope you never forget your seatbelt, you'll get thrown through the dump truck. :roll:laugh:falldownlaugh ointlaugh:waving
what the hell is a yanmar LMFAO is that similar to a takeuchi skid steer lol
Oh hell...thats to dang funny...just reading some old posts and this one got me laughing...you guys are hellarious !! yep... I think ill trade my 70,000 pounder in for a yanmar....or better yet a Tecumseh skid steer..:falldownlaugh thats to much !
Came here to read about the overheat issue like mine on the 350dlc. Going to check my fan motor and pump output. As far as yanmar goes.....did you all forget that a lot of minis from different brands run a yanmar engine???
Or that Yanmar and Deere are (were) in bed together.
This is one we rented while my 300 was ill... it was a pleasant well maintained rental. However you really need to be diggin' like lightning to dig with the 300. The rental guy probably forgot to ship the high speed G suit! So I could never get up to mach... note the paint was not scorched by re-entry swing speeds.