I replaced the coolant about two years ago right after I got the tractor. There was a lot of sludge on the bolster drain plug. I suspect the coolant might have had stop leak in it to keep the head sealed but it eventually opened up with straight 50/50 mix in it.
I'm not real keen on replacing the head right now. The tractor is burning some oil and at some point I'll need to tear it down for a rebuild and would prefer to do the head at that time.
Short of replacing the head I can think of 3 options:
- Add a stop leak product to the coolant and hope that closes it up
- Attempt to solder the crack with the head on the engine
- Attempt to braze the crack with the head on the engine
I'd appreciate any thoughts/experience on which approach to take.