Mariner 25hp outboard spark problem.

[Steve zodiac]

Hi, has anyone come across this problem before, I purchased a mariner 25hp two stroke ( 1980s) it was used 3 times from new, put in a dry garage for 29yrs! ..no corrosion or damage, looks new but when tried to pull start it it has NO spark. I changed the plugs ...nothing, I disconnected the white wire to disable the kill switch..nothing, could it be cdi box? Does this type of thing just happen...as it was kept dry and untouched for so long. It looks like Yamaha emblems on the engine if that rings a bell . Thanks steve.

 

[peteK]

Could be the points need cleaning if it has them.

 

[Steve zodiac]

Could be the points need cleaning if it has them.

No, it has a cdi box, it seems to look hardly used at all, I just at this point don't want to start stripping it, but thought there may be checks I can do whilst it is in 1 piece. Thanks. Steve.

 

[trialframe]

I've got an 8hp 2 cylinder yamaha 2 stroke & if you try to see a spark by holding a spark plug against a metal part of the engine - you can't see anything. Yet it starts well. Even if the plugs look OK - try a new set.

 

[Steve zodiac]

I've got an 8hp 2 cylinder yamaha 2 stroke & if you try to see a spark by holding a spark plug against a metal part of the engine - you can't see anything. Yet it starts well. Even if the plugs look OK - try a new set.

Thank you so much, I will try it and let you know. Steve.

 

[trialframe]

I'm not familiar with your engine, but in my experience it's more likely to be carburettor problems. Petrol dries up in the carbs & blocks some of the tiny jets. I got a small syringe of petrol & squirted it into the air intake while cranking it - this caused it to fire for a few seconds. That would rule out ignition problems.

 

[Steve zodiac]

I'm not familiar with your engine, but in my experience it's more likely to be carburettor problems. Petrol dries up in the carbs & blocks some of the tiny jets. I got a small syringe of petrol & squirted it into the air intake while cranking it - this caused it to fire for a few seconds. That would rule out ignition problems.

I will also do this ,thank you for your help. Steve.