im looking to buy a 1978 drott 40 on tracks but owner says it overheats after 20 minutes of running...he says when it reaches 190 he shuts it down...he seems to think its caused by a stuck valve in the hydraulic port...i dont see how that can be but what ever...i will check to see if the water pump is working along with air breather blockage, blocked rad and see if the therm is stuck....its a 4-71DD...what else should i look at?
Bring an infra red thermometer and take the temps of everything as it warms up and after the owner shuts if off at 20 minutes. The exhaust manifold to see if one cylinder is hotter than the others. Wherever the hydraulic port is that has the stuck valve to see if that heats up. The radiator top and bottom to see if it's plugged, once the thermostat should have opened.
190 ain't hot, 240 is hot. 250 is usually blowing steam from the radiator cap. Hydraulic heating if the cooler is in front of the radiator will do it.
let me rephrase ...he shuts down when it gets to 190....it has been way past that
10-4
I think it actually has a 53 series DD in it unless it has been Tim Taylor'ed . For the hyd. to cause a engine over temp, it will have to be hotter than a two dollar pistol! It may be the cause but you ought to look at other things first. One thing that comes to mind is not running the engine full speed and lugging it around. The two cycle engine is semi air cooled so you need to run it against the gov. to keep the blower speed up.
no..its a 71...im not new to them....and it was running at full throtal
thermostat, plugged radiator, from way out in left field, low oil or coolant. ?????
Drott Do you know about Drott excavators? I was wondering why if anyone knows why the Final drives are and have always been a problem. Is this lack of maintenance or just abusive behavior on the part of the operator.
Hey Delmer, I have Case 980, all most same to the Drott 40. Do you know anything about the final drives and why they often fail?
I would look at the Radiator fins, They do clog up with dust and dirt. Simply things like stuck thermostat.
Start with the simple things, clean the radiator, you might have to remove the hyd oil cooler to get it clean. Even if it looks like it is clean a good scrubbing usually makes quite a difference. With these older machines you get oil leaks, then you get oil on the radiator, then dirt sticks to it and then it's overheating. Most of the cooling systems on these machines were barely able to keep them cool in good conditions so it doesn't take much dirt to get them to overheat. Regarding the final drives being a weak point, it is mostly just the design. A lot of this generation of excavators had final drives with shafts and bearings that are just a little too small or weak for the job. They can barely take the stress of normal working conditions, put them in any hard work or slight abuse and they break. They are not like the planetary drives on modern machines, just keep some oil in them and they can take just about anything you can throw at them.
No sir, sorry.
one thing i know...neve never never try to drive with brake on..you will strip the splines on the drive shaft
Drott/Case Thank you for your reply. Was there anything case changed on that style of final drive to make it more sound.
So, Did the overheating issue of the OP ever get sorted. Always good to know the outcome as it may help someone else down the road.
He was looking to buy and That's as far as I know. 30 years of hard labor will get the best of us sooner or later. Hopefully a lot later. I bet that old Drott been worked to get this far, and still there to make another run at it. Good luck whoever get her. Hope its good home whomever gets it!.