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79 Evinrude 25 hp Won't Start

7

79Evin

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Ok I have tried just about everything to my knowledge with this thing. It's a 79 25 hp Evinrude that my dad gave me. It's was running however now that it's sat for 12 years it will not fire! I bought a new gas tank and fuel pump lines ect.. I am getting spark to both plugs ( not sure if it's strong enough) I am getting fuel. I pulled the carb and cleaned it. I have good compression 130 psi on both cylinders. I'm not getting any fire whatsoever. It has electric start. I've tried starting fluid with no luck. Only other thought is timing but how would that be off if it ran the last time it was used?? Any help would be appreciated. Thanks!
 
Welcome to the Forum. Do a spark gap jump test. Should display a crackling white/blue spark nearly 1/2" . Test spark with both plugs removed, fully charged battery. You can have a #2 Phillips screwdriver, and insert it into plug boot. Carefully holding onto the insulated grip on screwdriver, hold the side of the screwdriver....shaft....about 1/2" from the motor block, or say a coil mounting screw. Have your assistant crank the motor. Be sure to keep fingers clear from rotating flywheel. Remember that when the starter is activated, things may shift and move. My guess is a weak spark. If not....do you have new spark plugs?
 
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Weak spark is often a power pack on these. They can go bad just from sitting in storage. There is a charge coil and a sensor under the flywheel which sometimes get bad or possibly the final ignition coils. The aforementioned components can be tested using CDI trouble shooting manual which you can find online. You can access it for FREE.
 

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Yes, I just got one at the auto parts store. Better idea: I cherry pick batteries at the local junkyard. Known Steve, Jerry and Butch there for 40 years.......$35 bucks each.....find em fresh.....look at the date....load test em.....choose the big ones.
 
Boobie said:
I've seen "new" batteries not pass a load test !!
Click to expand...
Yep. I have a jet ski with direct fuel injection and it requires a minimum 10.5 volts to fire to the fuel injectors. This summer I went to a local battery shop and bought a brand new battery, took it home, and could not get the ski to fire. Took out the battery, put it on a deep cycle automatic charger, and let it do it's thing. After reinstalling the battery the ski fired like a charm.

Lesson: just because the battery is brand new it doesn't mean that it's at full charge.

KJ
 
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