Mercruiser 470 choking problems

boater_bill

Cadet
Joined
Jul 24, 2014
Messages
9
Hi guys, I haven't been here a while but I'm at the end of my rope and need some help. I know this is a moody engine to begin with by it's so good when it runs, I want to keep it.
I got a mercruiser 470 on a 19 foot sea ray, since I got the engine I change the following on it over the last 3 seasons:
Changes the alternator with a conversion kit, rebuilt the carb, changed the starter/battery, changed the fuel pump/fuel lines.
Now when I started it this season it runs fine at first but then after the engine warms up and I do a warm start it has problems turning over. I tried setting the timing and can only get it started while butterflying the choke on the carb, but as soon as it turns off it's difficult to start again. It has been 2 seasons since I rebuilt the carb, and I'm thinking of doing it again or just replacing it, what do you think? Any advice on this would be greatly appreciated, I keep replacing & fixing these issues but the problem keeps coming back, is there something I'm missing, or anything else I can try?
Thank you for your help:)
 

kenny nunez

Captain
Joined
Jun 20, 2017
Messages
3,487
Which starter do you have? Is it the later style with a solenoid mounted on top or the earlier torpedo shaped style?
It may be the “by pass” circuit that provides 12 volts to the coil when cranking, there is a small purple wire on the solenoid below the manifold that should have 12 volts when cranking then around 8 volts when the engine is running. This wire goes to the + side of the coil and if there is no current present when cranking this might be the problem.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,389
and can only get it started while butterflying the choke on the carb,

Ayuh,..... Welcome Aboard,...... Does that mean closin' it, or propin' it open,..??

If it means opennin' it, it shouldn't be closed,.... Fix the choke,....
If it means closin' it,... the carb ain't supplin' gas properly,... Rebuild the carb,....
 

boater_bill

Cadet
Joined
Jul 24, 2014
Messages
9
"Which starter do you have? Is it the later style with a solenoid mounted on top or the earlier torpedo shaped style?
It may be the “by pass” circuit that provides 12 volts to the coil when cranking, there is a small purple wire on the solenoid below the manifold that should have 12 volts when cranking then around 8 volts when the engine is running. This wire goes to the + side of the coil and if there is no current present when cranking this might be the problem."

It's the old style torpedo. I've been meaning to change the starter, I may have damaged it from all the attempts to get it started. Should I get the same torpedo style or the newer style with solenoid on top?

Also, I'm putting a new carb on it to see if that solves the proble.

Thank you.
 

stonyloam

Vice Admiral
Joined
Mar 13, 2009
Messages
5,830
NO! Get a modern perminant magnet gear reduction starter. Attach the current starter wire ( red yellow I think) to the solenoid of the new starter. Your current solenoid now becomes a slave.
 
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