Starting a Mariner 5 outboard

[cat ketch]

I have a very reliable Mariner 5 4/st. but I had a problem today and wonder if anyone has any suggestion. When I tried to start it it fired very weakly for 4 or 5 times and then gave like a weak back-fire and stopped. This happened about a dozen times. I was about to give up when it fired and ran smoothly. As usual it start first pull when I was returning to the pontoon but, it has dented my confidence in the engine.

 

[andsarkit]

Is the choke linkage operating correctly?
If the choke is not enriching the mixture it may fire but not run. After several attempts it may eventually start and it will then start again if it is still warm.
It may be necessary to dismantle and clean the carburettor as modern fuel tend to produce a nasty sludge if left in the float chamber. The small jets in the carburetor are easily blocked so at least you could remove the float chamber and check it is clean. It is a good idea to turn off the fuel and run the engine until it stops so it is left with minimal fuel in the carb.

 

[wallacebob]

Use fuel stabiliser, premium petrol ( E5 + additives) and remove carb and have it ultrasonic cleaned. All issues will be gone. Until you need to change the plug.