long start adjustment?

edrauch

Cadet
Joined
Jun 11, 2009
Messages
6
I have a 1993 alpha 1 gen II 350 mag. It runs like a top but i always have to crank it for several seconds (up to 15 seconds) to get it to fire and start up. Just wondering what the sugestions are to start trouble shooting this? Carb or choke adjusment? Thanks
 

PitchFork

Petty Officer 1st Class
Joined
May 28, 2009
Messages
313
Re: long start adjustment?

It could be the choke. Make sure the choke butterflies are almost closed with 3/16" from the airhorn. It also could be that the anti-siphon valve at the fuel tank pickup is not working correctly. It is allowing fuel to run out of the fuel line from the carb. When I got my boat two years ago the choke was fully open and it had a straight-through valve and the fuel would run out from the carb. The only way to start it after sitting for a day would be pouring fuel into the butterflies.

You may have to adjust choke rod and replace the valve. Besides making sure a tuneup has been done. Does the boat idle and run fine after you get it started and warmed up? If so then it is probably either or both choke and anti-siphon valve.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: long start adjustment?

Do you use the throttle when stating or just leave it at idle till it starts?
 

edrauch

Cadet
Joined
Jun 11, 2009
Messages
6
Re: long start adjustment?

Thanks for the replies. Boat runs fine after it is started and starts every time. I do use the throttle when starting. I ussually have to pump it a couple times and then leave it at 1/2 until it starts. Idles fine and runs great after it is started. E

Just checked and 3/16" dril bit fits between the fly and the carb wall.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: long start adjustment?

With the engine off and cold. The choke should be closed completely.
To adjust, just open the throttle a little, then turn the choke coil to just put some pressure on the choke plate in the closed possition. Merc likes to add quite a bit of pressure, but it just causes a lot of excess smoke on an engine that doesn't need that much.
Then look at your flow from the accelerator pump. Is it two good streams when the throttle is pumped. If not, that could be your problem.
It could also be your engine is just in need of a full tuneup, (including compression check).
 

edrauch

Cadet
Joined
Jun 11, 2009
Messages
6
Re: long start adjustment?

Thanks for the replies. I'll go to work on the anti-syphon vave and the choke this weekend. E
 
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