Engine problems.

[InTheBox]

HI guys,

I have a 350 merc I/O. i have a hard time starting it. It seems like it doesn't want to fire over. You got to keep turning it over and pump the throttle into it starts. It also will stall sometimes when you put it into reverse after running it for awhile. Had the carb rebuilt and it still does this. Any ideas at all?

Thanks,

Pat

[Diversion]

How old is your fuel? Could be as simple as bad / stale / water saturated gas.

[skipper19]

Not sure what outdrive is on it but some have a safety switch on the lower shift cable. Check the adjustment, or maybe you need a new shift cable. Does it seem to just shut the ignition down, like turning the ignition off when shifting, or does the engine blubber and then slowly stall out on the shift. If it blubbers and quits and you always have to pump the throttle, you might have an intake vacuum leak somewhere below the carb. Make sure there are good vacuum hoses attached to the carb and PCV. Once it is running, if you can spray a short blast of ether around the intake manifold to head junctions and around the carb base to manifold area, see if the engine revs up when you spray the ether. Make sure the ether does not get to the carburetor throat, or it will false alarm the test. If the engine temporarily revs, there is a vacuum leak at a gasket. Try tightening the bolts.

A vacuum guage attached should read around 17- 20 inches vacuum on an unmodified 350.

Could be a number of things, but start with that and then go to ignition. Ignition timing is directly related to intake vacuum as well so if you can check the timing it would be an easy fix if all you need to do is advance the timing a bit, but beware of too much advance, especially with this junk gas we get from the gas stations with ethanol in it.

Hope this helps

Mark

[Big Dave]

My boat is older, but I had the same starting problem. I have points and a coil. The starter solonid is susposed to send 12v to the coil when cranking. It wasn't so I had like 2v to the coil when starting which isn't enough. Your boat looks to be newer and may have a different ignition system. Just something to check if you have points and a coil.

[L&M]

Let's not get to technical here. If I had to guess with out seeing it I would say a fuel issue after setting all winter. IE: condensation in the tank= check water separator if installed & run it low on fuel before you put fresh fuel in it. Reverse could very possibly be a sticky lower shift cable, put some time on it and see if it still does it. If not it will have to be addressed. If I can help you out feel free to contact me.

[InTheBox]

Thanks guys. Ill try out the tips that i got from you guys and let you know how it works out. The gas is almost all new. There was 1/8 of gas left from last year. I have to put some gas in the boat friday and ill put in some stabil.

Thanks again guys,

Pat