540 wont start.

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terrible ted
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540 wont start.

Post by terrible ted »

Well I think it a carb issue but I my arms not long enough to check for spark by my self. I noticed fuel dripping from carb. If I cant figure it out is there any mechanics one near Orlando my neighbor and friend passed away.

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Slidin Gator
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Re: 540 wont start.

Post by Slidin Gator »

Put a timing light on it to check for spark. I just tie wrap the trigger, crank and watch for flashing. Wack the bowl to see if it frees up a possible stuck float.
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.

terrible ted
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Re: 540 wont start.

Post by terrible ted »

That's why I post on hear things I did not think of. Is there a fuel drain screw incase water is in bowl I believe I have a ma6? not a 4-5.
I know if water gets in the bowl that that can stop it from starting.

GMAC 76
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Re: 540 wont start.

Post by GMAC 76 »

terrible ted wrote:
Mon Dec 02, 2019 7:06 am
That's why I post on hear things I did not think of. Is there a fuel drain screw incase water is in bowl I believe I have a ma6? not a 4-5.
I know if water gets in the bowl that that can stop it from starting.
there are actually 2 bowl drains on the MA-6AA carbs one on each side if the fuel shut off lever on the bottom of the bowl

terrible ted
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Re: 540 wont start.

Post by terrible ted »

I was not sure. not sure if it water.

terrible ted
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Re: 540 wont start.

Post by terrible ted »

ok looked at the boat appears no power to the mags. Correct me if I am wrong but no voltage on the wire to the mags with the switches on is not good. I will check inside the control box next, the easer fix is welding the cage were a bar broke. seams like I am Destin to have to work in the dark.

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Slidin Gator
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Re: 540 wont start.

Post by Slidin Gator »

Ted,
Your switches ground out the mags to shut them off. You do not send power to the mag, it makes it's own. Mags ungrounded=live. Mags grounded = off. In either case there should not be 12V on the wire ("P" terminal wire).

Did you check for spark at the plugs?
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.

terrible ted
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Re: 540 wont start.

Post by terrible ted »

I never worked on mags before I was thinking it was more like a car. So both stopped working. So If neither are firing?

terrible ted
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Re: 540 wont start.

Post by terrible ted »

Is it od both quit at same time?

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Slidin Gator
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Re: 540 wont start.

Post by Slidin Gator »

Call me, I'll walk you through it.
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.

Gary S
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Re: 540 wont start.

Post by Gary S »

Ted are you sure both were working before? One could have not been working and you didn't know it unless you do a mag drop test. Which is something a lot of people don't do.

terrible ted
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Re: 540 wont start.

Post by terrible ted »

I start with one mag on makes a good difference less stress on the starter 10:1. The county made me take my canopy down and the boat was outside to much. Over about a 2 months of being to busy They have died. I have limited time to work on it. It has not been started in 2 months. So if either of you can describe what might be wrong or how to test it. Yea I mechanically inclined but never worked on a mag. Rebuilt motors cars was an ASE certified mechanic 20 plus years ago.

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Slidin Gator
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Re: 540 wont start.

Post by Slidin Gator »

My suggestions are simple, confirm if the mags are producing spark, use an inductive timing light or an in-line spark light to confirm. If no spark, pull them off and send out for a refurb. GMAC76 is a good option, he will get you back running quickly.
I still think I-10 is the Mason Dixon line.
2013 Mike Stossel Boats, 13' x 7' deck over, IO-540, 74" NGQ less winglets.

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