Rough Start on Big Block carbs

[SkiPharmer]

I have a 1995 330 with big block carb V-Drives, sometimes when i first start the boat after its been sitting for a while, it can sound kinda rough, as if the engines aren't getting water (just replaced new impellers last August), with in 5-10 seconds tho the water is coming out of the thru hulls and it runs fine. Is this normal? I thought this was normal as it takes a while for the water to come up and cycle through the exhaust, but my dock neighbor didn't think it was normal.

Thanks again, this Forum as been AMAZING!

Chris

 

[Alegria]

Not sure what you mean by rough exactly. I can't say for sure if water starts to flow immediately on mine. Usually takes me 5-10 secs to get back there to check. From the forum here I'ved learned a start up routine. I usually turn the engines for 2-3 short bursts. Then pump the throttle to get fuel into the engine, which I just sucked from the tank on the turns. Then 1 or 2 more short bursts on the starter and they turn over. I then let them run at around 1100 rpm for a minute and then take them down to 600 rpm at idle.

You are correct that if you do not get sufficient water flow intially you will hear the raw ehaust of the motor until the water muffler fills up with water and starts dumping over the side.

 

[Mike Blake]

I have the same engines. It sounds like the choke may be sticking or just not opening up as soon as you want. Get some carb cleaner and spray the top of both carbs.

 

[Creekwood]

My boat is the same setup as yours. When its first started, it takes a bit of time for the water to fill the mufflers, so you are listening to raw un muffled big blocks through the side exhaust. Its like music to my ears. I love the sound of those big boys firing up. You said "rough", but if you mean louder, then that is just normal, until the mufflers fill and water comes out the side. Maybe 10 seconds on my boat..