I have a John Deere 200CLC, 9k hours its a pretty solid machine. She runs great the only issue is I have to keep adding coolant. I have put around 120 hours on it and in that time I have added at least 6 gallons of coolant that I can remember. So by my math that is about 1 cup of coolant per hour. I would think that would be enough that I could see a leak somewhere if it was leaking from the radiator, pump or a hose but I can't find any leaks. That would make me think head gasket but the oil and coolant are both very clean and I get no bubbling out of the radiator. It also starts really easy, has a little smoke on startup but nothing that seems abnormal, once its warmed up the exhaust is very clean and doesn't smell sweet at all. I hate to pull the head off for no reason and don't plant to do anything until I find a smoking gun or the consumption gets worse just wondering if anyone has some thoughts about what the issue might be or what else I should take a look at.
Lots of tricks to the trade. Start by pressuring the cooling system with a tool and start looking. Add some UV dye and use a light. Pull guards off and start digging. Could be your heater core where you don’t expect it. Water pump weep holes leaks can evaporate before you see them.
Good feedback, I was planning to throw some UV dye in there, hadn't thought about pressurizing the system that is a good idea. Thanks.
Keep us updated. Good luck.
Big thanks on recommending that tool. Pressured it up to 15 psi for an hour and it held. Took a closer look at the cap and it's in bad shape I doubt it could hold 1 psi. Guessing that's my problem. It's so easy to miss the little things.
That’s great news. And a easy fix.
Yeah my only concern now would be if there is a leak at operating temperature of the engine. That isn't open when the engine is cool. But I'm optimistic it's just the cap, it had to be losing a decent amount through the cap there is no way that was holding any pressure. Photo of said cap: