Engine rough start

[bmatt]

I've taken my boat out 3 times so far, the first two times it ran fine, but the third time I took it out it ran really rough when I first dropped it in. I putted over to the dock shut it off and popped the dog house to check for anything obviously off but didn't see anything. Got in and cranked it back up and it ran fine. I just got some muffs and hooked them up in my driveway and cranked it to check it out and it did the same thing. I only left it on for about 30 seconds in the driveway.

I am pretty sure it is idling too low and maybe this has something to do with it. When I am in the marina putting around and switch from forward->neutral or reverse->neutral it will stall out sometimes. When I am on the lake going around I never have any problems with it stalling going into neutral.

[seapuppy]

I'm assuming it's a carb'd engine...if that's the case....check the torque on the carb...use a bottle of soapy water in a squirt bottle......with the engine idling rough ...squirt the base with the soapy water....use the stream mode....if the engine smooths out for a few seconds...you have a gasket leak...which to me makes since it only happens when cold...the gasket might be shrinking while it's cold....if that's not it...check the choke out..when it's cold...pump the throttle once to set it...then see if it's closed all the way...if not .....then the choke needs work....


SP irate:

[bmatt]

Hmm, cool, I'll give that a try. The guy I bought the boat from told me to start the boat by putting the throttle in neutral pushing it forward until you get a little bite and then crank it, with the throttle slightly open. Then when it starts I adjust the throttle to around 1200rpm or so and let it warm up a bit. Is this the proper method or could that be causing some of my issues? Should I be pumping the throttle wide open and then back to close and then cranking?

Also, I assume with the test method you mentioned I should open the dog house, take off the flame arrestor and tighten down the carb where it attaches and then crank it with the arrestor off. Then spray around the base of the carb where the bottom gasket sits?


Thanks!

[seapuppy]

actually the correct method I've always used is;
1)put throttle in neutral and pump 2 times...(this sets the choke and pumps gas into the carb)
2)move throttle to about an inch or two fwd (this allows the engine to get some rpm's when it catches)
3) adjust to about 1000 rpm and let warm up...boat will increase rpms as it warms...reduce to 1200 rpm as it increases....
4)when temp reaches operating temps....pull throttle back to idle..
5)put in gear and have fun..

for the check...yes you need to gain access to the carb by removing the flame arrestor..take it off before you first move the throttle....

proper idle speed is about 600-650 rpms on a carbed engine...

SP

[bmatt]

Well I just tooke the flame arrestor off and there was a little hose that was loose on the mounting bracket, hooks on top of the valve cover I believe it is. I took it all apart and check around everything seemed to be in good order. I cleaned off everything and made sure that hose had a good seating, think it probably is missing a hose clamp that should be there?

Anyway put the flame arrestor back on for kicks and tightened it back down then hooked up my muffs and turned the water on. I pumped it forward before starting it this time and then pushed the throttle up to start it. It seemed to start and idle a lot better that time, still a little shimmy but I think I've read that the 3.0L is just that way. I did put some fuel stabilizer in last night too, maybe that had something to do with it, but it seems to run a lot better now. I think I'll stop tinkering till the end of the season, I tend to work myself up for no reason often.

[seapuppy]

that hose is just the crank case ventilation .......it takes overpressure coming from the pistons and the flying oil vapor and injects it back into the engine....so...probably doesn't need to have a hose clamp on it unless it comes off..then put one on it....

and there ya go!!...you just learned how to start the engine and get it to idle....


SP irate:

[bmatt]

Cool, thanks for the help! If only the guy I got the boat from would have told me the right way? lol

[seapuppy]

he got your money...he's done!!..haha..


SP :hello: