Yanmar 2gmf
My old boat, a 29.5, had a 2gmf Yanmar engine that was extreamly hard to start during cold weather. My wife would hold a hair drier on the air intake to warm the air to make it easier to start, while it worked, I wasn't happy with the solution nor was my wife. I called Mack Boring, the Yanmar distributor in the mid-atlatic region, and they had all kinds of things for me to try and recomended that I buy the shop manual, which I did for about $45. While I was reading through it, the manual had a very small section on hard starting when very cold. Yanmar recommends moving the throttle to the wide open position because it advances the timing a bit. I tried this and it works! While it may not start as easy as yours, our engine would require about 3 cranks to get it going, it does work and required no modifications. You need to use caution when using this tecnique however, and reduce the throttle as soon as the engine catches, because you don't want to run any engine at wide open throttle when it is first started, especially a diesel . The funny thing is that the neither the dealer or the distributor knew anything about this cold weather starting tip from Yanmar and its not in your owners manual. It worked for me with our 29.5 and now that we have a 340 with a 3 gmf Yanmar engine, I'll give it a try. The boat is just being commissioned and hopefully, cold weather is over until late October.
