YM2000 Problem

[GreenGuy23]

Hello Everyone.

I have done some research here before but I have a problem with my yanmar I need help with.

I have replaced the head gasket on my yanmar 2000 twice and am still having air bubbles in my overflow tank but really no other symptoms.

The bubbles are not frequent but they happen. I was told it could be air purging but I have ran it for a couple of hours total. Would air still be purging? The coolant level has dropped a little (about .5 - 1 inch from the full line on the overflow tank).

The radiator is new. I have taken the head to a machine shop and had it leveled. I still can't figure out what the deal is. There isn't any water in my oil (looks as gold as the day I put it in). There is no oil in my radiator either. So I don't know what is going on.. Anyone have any ideas?

All help is greatly appreciated.

 

[stormpetrel]

Cracked block/head? Is the engine otherwise running....good power, not overheating?

I don't know how else gas would be getting in to the overflow bottle. Interested to hear what others think.