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40 Hp mercury

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elf0678

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Hi Folks. First time here. I can't seam to find the answers on my own so I thought I'd try this forum. I have a 40 horse Mercury, Serial # 5368672 which the best I could find out it's a 1979. I don't get no fire at the plugs, coils, stater or the switch box. The rectifier shows fire at the + side. Someone please help me, I'm no mechanic but I catch on pretty good. Also I'm retired living on disability so I need to know what the culprit is. I can't afford to try this and try that. Any help on testing would be greatly appreciated.
 
Start simple first, Make sure your safety switch on the controls ( If you Have It ) is on run and not off. If you have a main fuse on the motor check that also.
 
I don't have a safety switch. I don't think I have a main fuse either. I am getting 12 volts back to the silinoid. but that's as far as I can trace the voltage. What's next?
 
I would think the first chain of command would need to be tested first then move down the line to each component. You will need a ohms meter and have to know the proper reading for each item on that motor.
 
I have an ohms meter and I have the chart for the ohms reading and voltage. I don't know how to check the rectifier, I have 1 + wire and 2 yellow wires coming from the stater. I found one way to test for ohms but it referred to the wires as A, B and C but I don't know which one is A,B or C
 
All them have a fuse, if you have 12volt at solenoid and stater and choke wont work its bad connrctions at battery or blown fuse...
 
OK I'm back. The rectifier is OK I believe. Now how do I check DVA with my multimeter? Is it the same thing as DC. I touched the red and blue wires from the stater both connected and disconnected with my DC setting while cranking the motor and I got nothing. Help please.
 
does this mean my stater is bad? I need to get back fishing soon so any advice is appreciated very much. I found a stater on ebay for $218. but I need to know for sure before I shell out that much. Thanks in advance.
 
You can't test DVA with a regular multimeter unless you get a DVA adapter. DVA is a "pulse reading" used primarily for testing and diagnosing marine/outboard ignition systems. Make sure you test all components before installing any new parts. Check cdielecronics.com as mentioned above. They have a fantastic free manual to use on-line. They just want to sell you the parts you need.......a great company.
 
I'd like to thank everyone for their help. I just took the plunge and ordered a CDI Stater on line and it will be here Friday. Will let you know if it fixed it.
 
Be sure to check flywheel magnets too, they can get loose and cause big problems. Check trigger for short to ground or open loop in all throttle positions.
 
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