Rough idle at launch

[Cuddy]

Every time we launch, it takes some time for the boat to "warm up". The wife is usually at the controls of the boat while I back the vehicle so I can't say for sure what is happening but the boat fires right up then will die when you go to reverse to get off the trailer. The normal idle is fine - about 800rpm. Any ideas or techniques?

 

[Backlash]

Re: Rough idle at launch

Hey Cuddy, We need a bit more info to give you any advice, i.e., what engine powers the boat, did the problem just start, any history of previous repairs, etc. The more info you can provide the better. <br />Backlash

 

[Cuddy]

Re: Rough idle at launch

No worries, it's a 2001 Bayliner powered by a 140 hp Mercruiser I/O. Less than 50 hours on the engine/boat and it's done it since nearly new. No previous repairs or problems with the exception of a unintentially modified skeg that the fine folks on here helped me out with.

 

[grandx]

Re: Rough idle at launch

After engine is warmed up, does it still die going into gear?

 

[Cuddy]

Re: Rough idle at launch

Runs like a champ as soon as it comes off the trailer. No stallings.

 

[Backlash]

Re: Rough idle at launch

Try setting the idle up a bit. I'm not sure what the specs call for but if it's at 800 now, setting it to 900 or so shouldn't bother anything. Let us know if it helps.<br />Backlash

 

[grandx]

Re: Rough idle at launch

Engine can be tuned to run cold or warm, most are tuned to run warm. Let motor warm up while boat is on trailer then back it off. I wouldn't increase idle if everything works fine warm. Can be difficult to get into/out of gear if idle is too high.