Does anyone recommend any websites for parts online for an older Takeuchi? Seems like I can hardly find anything even with using proper part numbers and numerous related searches. I recently purchased a 2000 Takeuchi TB125 mini excavator with an intermittent cooling issue... Seems more flow related like debris inside is maybe causing captivation at times... In any event after trying a new thermostat and radiator cap my next thought was a new/rebuilt water pump and radiator just to get the best jump on this as possible however having a difficult time finding parts online... Does anyone recommend any websites or parts ordering sources?
I can't help you with parts, but it sounds like you're heading down the road to become a "parts changer". How about diagnosing the problem first? What kind of cooling issues are you having? Does it lose water before or after it gets hot? What kind of conditions? Have you taken the radiator out and blew all the dust off, and flushed internally?
Try here as I have purchased parts for my 2005 Tb125. http://www.andersonequip.com
Yes I have flushed the radiator and it is externally clean with very few bent fins that i straitened... It is able to maintain temperature in the upper 2/3 portion of the green at low RPM however the issue presents itself at higher RPM's. There is no coolant loss or water in the oil so I don't think it is a head gasket... I even tried a large external fan to get more airflow thru the radiator without luck... The engine compartment seems a bit suffocated on these units however running with hood open or closed makes little difference... My biggest suspect is the water pump at this point mainly because I dont see a lot of movement in the radiator cap (however upper hose is opposite end of cap) and when i pinch a hose even at high RPM I do not feel an obvious flow, hard to be sure with vibration etc however it seems I should be able to feel the restriction I create by pinching a hose...
Use a infrared thermometer to check the temperature of the coolant going into the radiator and coming back to the engine. The hose nipple on the thermostat housing and wherever the return hose attaches are good places, or you can shoot the hose itself, just don't use a shiny metal surface it won't read right. Nige says 20 degrees difference is the maximum. Less than 10 degrees F and the radiator isn't getting enough airflow, IMO. More than 20 there's not enough coolant flow, either water pump is bad, radiator is plugged. OR the engine isn't up to temp and the thermostat is still closed, obviously the temps will reflect that. Not feeling the flow doesn't surprise me, it doesn't take much pressure to move the coolant a few feet through the radiator and back, and it doesn't take that much restriction to slow it way down. I have no idea what the antifreeze looked like, how often it's been changed, how much pond water has been added, etc. but unless you know the water pump impeller is plastic or something else obvious, then I'd bet on the radiator being plugged externally, possibly internally, the temps should tell which. The belt is tight, right?
The Hydraulic oil cooler is mounted in front of the radiator, is it clean and how hot does your Hydraulic oil get ? as the heat from oil cooler passes thru the radiator.