Coil

[Scott06]

Would this happen even when the motor is cold? Boat fires right up runs good. Then about one hour in it cut off and cant keep it running. Then when motor cool down runs normal.

yeah got that it happens after an hour.

maybe maybe not ...you have to look for what's missing (spark or fuel) when it acts up. everything else is conjecture.

 

[Bt Doctur]

Heres a few east tests,
4ft 18Ga wire with alligator clips
When it happens check for 12v at the + side of the coil, if none jump from + battery to + side of coil ,see if it now starts
When it happens check for spark ,if none;
jump from + battery to the + side of the coil ,test .If now spark and motor runs ,suspect the ballast resistor (if equipped) or the resistance wire coming off the elec choke
If no spark then suspect the coil BUT first remove the wire on the neg side of the coil
test by scratching the jumper from the - battery side to the - side of the coil, with 12v present at the coil , this should generate a spark .
no spark ,replace coil

 

[corytha]

Heres a few east tests,
4ft 18Ga wire with alligator clips
When it happens check for 12v at the + side of the coil, if none jump from + battery to + side of coil ,see if it now starts
When it happens check for spark ,if none;
jump from + battery to the + side of the coil ,test .If now spark and motor runs ,suspect the ballast resistor (if equipped) or the resistance wire coming off the elec choke
If no spark then suspect the coil BUT first remove the wire on the neg side of the coil
test by scratching the jumper from the - battery side to the - side of the coil, with 12v present at the coil , this should generate a spark .
no spark ,replace coil

Thank you.

 

[Scott Danforth]

New carburetor

Where specifically did you get a new Rochester?

 

[corytha]

Where specifically did you get a new Rochester?

Serria

 

[corytha]

It was definitely the coil. Ran pretty good for a Couple of hours. I will adjust the timing and the dwell this week. And tweak the carburetor as well. Tell me what you think on video about the carburetor.

 

[corytha]

You can test the coil in question with a multi meter. Chances are its not the coil, they do fail but rarely.

It was the coil.

 

[corytha]

Seems your hung on changing the coil, I say do it, they are not expensive and your mind will be at ease, especially if it cures your problem.

It was the coil.

 

[corytha]

Thank you. I will be look tomorrow.

It was the coil.

 

[Scott06]

It was definitely the coil. Ran pretty good for a Couple of hours. I will adjust the timing and the dwell this week. And tweak the carburetor as well. Tell me what you think on video about the carburetor.

ok we got it it was the coil no need to post it 4 times...

What is seen is typical of the chinesium replacement carbs about half of them work ok.

Either the accelerator pump is not working or has a delay in action due to slop in the linkage or you need to take it apart and adjust needle and seat /float. Seems to idle good did you set the idle mixture or is it out of the box? I think I had to run my 3.0 a little fat on idle so it wasnt too lean on transition to main jets

 

[corytha]

ok we got it it was the coil no need to post it 4 times...

What is seen is typical of the chinesium replacement carbs about half of them work ok.

Either the accelerator pump is not working or has a delay in action due to slop in the linkage or you need to take it apart and adjust needle and seat /float. Seems to idle good did you set the idle mixture or is it out of the box? I think I had to run my 3.0 a little fat on idle so it wasnt too lean on transition to main jets

I did adjust 1/8 counter clockwise. When I went in it would die out.

 

[Scott06]

I did adjust 1/8 counter clockwise. When I went in it would die out.

how far out from lightly seated is the mix screw? Normally should be in the 1.5-2.0 turns out range on a mercarb or rochester.

when setting you can do it by ear or better yet use a vacuum gauge, turn it lean until it stumbles then go out until it stumbles rich. in between these two spots is normally considered best idle. I usually go a touch richer than best idle. Remember to adjust a bit then wait a few seconds for engine to respond be fore going further.

I'm not saying you are there yet but do you still have the original carb? 9/10 times with a little care you are better off rebuilding the original than getting a cheap knock off.

 

[corytha]

how far out from lightly seated is the mix screw? Normally should be in the 1.5-2.0 turns out range on a mercarb or rochester.

when setting you can do it by ear or better yet use a vacuum gauge, turn it lean until it stumbles then go out until it stumbles rich. in between these two spots is normally considered best idle. I usually go a touch richer than best idle. Remember to adjust a bit then wait a few seconds for engine to respond be fore going further.

1/8 from the preset Serra carb. I do have a vacuum gage. Yes I did wait to here the change. Thank you for your knowage.