New to Outboards - bought a 1985 50 hp Mariner but can't get it started!

[Learningboating359]

I've learned alot in two weeks about the electronics of an outboard boat engine! Know what a coil is, a stator, a trigger, switch box, etc. Had spark on one cylinder and none on the others. Pull coils off and cleaned and all tested within spec. Pulled all the wires off of switch box and cleaned terminals. Put everything back and I got spark on all 4 but no ignition. Check ohm readings on stator and trigger. The Trigger readings are within spec but stator I'm getting on 50 ohms on red to red/white (spec 56 ohms) and 1900 ohms on blue to blue/white (Spec 5700 to 7000). Is the stator causing my problem. The engine ran when I purchased the boat for a few minutes. I can't get it to fire up! Could it be fuel starvation? Plugs are not wet! Help!

 

[tavacska]

I am a newbie too.

For my understanding, you have to check.

1. Body,(compression)
2. Fuel,(carb, fuel line, gas, and etc)
3. Ignition ( switch, trigger, wiring, coil and etc).
4. Timing and idle set

All has to be done one by one. My mistake is to think it is ok but it is not. I will do a serious test for each part and confirm myself that it is 100% right. Otherwise, it will be a forever checking loop.

 

[racerone]

Answer this question.----Does spark jump a gap of 3/8" or more , yes or no ?

 

[Learningboating359]

On my way home, stopped at a local boat shop seeking free advice! The guy there was open to a few questions! Told him the symptoms and said he thought it was a fuel problem and told me to shoot starting fluid in the carbs! Tried that previous before I realize I had no spark! But decided to try again since I restored spark! Got home, hooked up the hose, Two tries with SF and I got ignition! Man was I happy to see that engine running! After 5 minutes, cut off and crank again and the ignition was instant! Ran for another 5 minutes! 30 minutes later tried to start but had to use SF again! Ran for another 30 minutes with Seaform in the fuel! Still might need a carb rebuild!

 

[tommarvin]

You want to eliminate the dirty/plugged fuel system first.
From clean fuel tank to the carb jets, remove and clean the carb,take it completely apart even remove the welsh plug,lots of small holes in there, if you damage a gasket buy a rebuild kit.
New on motor fuel filter.
Try not to use a lot of SF there's no two stroke oil in it,you don't want to scortch the cylinder..
.Sounds like your a handy man, get a factory service manual so you have the information to fix everything.
Install a fuel water separator, if the fuel lines are eight years old change them to USCG A1 marine fuel line.

 

[DeepCMark58A]

Step 1 for me on any motor is a compression test, by knowing if compression is good you know if it is worth investing $ to get the motor running.

 

[DavidMoore]

+1 to tommarvin

Your local boat shop gave bad advise re the starting fluid, safer for your engine to use ordinary gas with mixed 50 to 1 with 2 stroke oil.

Well done for getting the engine running, sounds like you need to clean the carbs.
Do the fuel lines leave a black mark on your hand? If so you should change them for modern ones, there is a good chance they are failing from inside out and can cause problems.

 

[Learningboating359]

Great to get all the advice from more experienced folks. Guy from my work provided me with a compression gauge so I?ll check that this weekend!

 

[Learningboating359]

tom Marvin -that?s some good advice!