Starboard Engine Will Not Start ... Big Problem?

[treeskier]

Went to take the boat out today port engine fired right up. Cranked starboard engine and it cranked a little but sounded very clunky and hollow sounding then it stopped cranking. Tried it again and it clunked once or twice and stopped cranking. Sound is awful when it turns over. Lanyard and hatch switches are good. Boat ran fine two weeks ago. I have a bad feeling about this. Any ideas are appreciated.

 

[itsdgm]

Hopefully it's something simple. I know we have a checklist on this site somewhere.

Here's what I'd check first:

Look at the spark plugs (color, wet/dry)
Check compression
Check the pump clearance (it's possible that the pump liner is swollen)
Check the starter

I'm sure guys with better Yamaha 2 stroke knowledge will chime in shortly.

 

[BigN8]

Crank the port engine and let it run for about 10 minutes. Then crank the stbd. Sometimes if your battery has low volts the first engine will start normal and the second starts hard and runs weird due to low voltage. Mine did this last year.

 

[treeskier]

Crank the port engine and let it run for about 10 minutes. Then crank the stbd. Sometimes if your battery has low volts the first engine will start normal and the second starts hard and runs weird due to low voltage. Mine did this last year.

I will give that a try. That is an interesting theory since we just had a week of bad weather from the nor'easter and hurricane joquian and I elected to leave the cover off due to several days of high winds. We did have significant rain so I am sure the bilge pump worked overtime.

Although it is a new battery and I have a norco gen 1 installed that was plugged in for the past few days I should have had a full charge but you never know.

 

[4x15mph]

I would take the spark plugs out, see what the look like, and then try to turn the impeller shaft by hand while you have the plugs out. If it doesn't turn, I would start by looking at the impeller housing/liner since these do swell. You may also have something jammed in the impeller. Keep us posted

 

[treeskier]

Problem solved...sort of. @BigN8's reply got me thinking back to earlier this summer when I had an issue starting both engines that was clearly battery related. So yesterday evening I attached my booster pack to the battery and the starboard engine fired right up. We used the boat to go to dinner fairly near by the water was calm so if we had to limp home on one engine it wouldn't have been that unpleasant. The boat ran great and both engines started on the first crank every time.

So I'm thinking that leaving the cover off during the nor'easter/hurricane last week where it rained part of every day for a week the bilge pump worked overtime (boat on lift plug is in 24 7) and drained the battery (even though I have a new battery, 10amp NoCo Gen 1 Battery tender and the fuel air separator with fuel pump) enough so that the starboard engine didn't have enough juice when cold to fully engage the starter bendix. I am thinking I have an issue brewing with the starboard starter that will need to be addressed at some point since it seems to require more cranking power when cold than the port engine.

 

[4x15mph]

Great to hear. What about the clunking noise?

 

[treeskier]

Great to hear. What about the clunking noise?

The clunking noise disappears when enough cold cranking amps are applied. I believe the clunking was the starter bendix not fully engaging the fly wheel due to insufficient juice being applied to the starter motor.

 

[itsdgm]

Glad to hear that you've got it figured out. That's great.