Outboard Spares and Outboard Engines, 30-40HP 4-Stroke Yamaha
Outboard Spares and Running problems with 4-Stroke Outboard Engines.
We are always getting asked for outboard spares Electrical Ignition parts for the Modern 4-Stroke Outboards. We always ask Why, the answer is usually a misfire, rough running, wont accelerate. These are not electrical problems, They are fuel problems usually caused by dirty carburettors, they should be completely stripped, cleaned thoroughly with Carburettor cleaner and put through a ultrasonic bath to remove any grit that could be lodged in the tiny passages of the idle circuit. Where there is more than oine carburettor these will also need balancing to ensure smooth idle and smooth pickup. It is very rarely Coil/CDI Problems as we always advise our customers.
Yamaha 30 and 40HP 3Cylinder 4-Stroke Outboards....
ALWAYS WEAR SAFETY GOGGLES AND GLOVES WHEN USING CARBURETTOR CLEANERS.
have a accelerator pump on each carb, it squirts a fine jet of fuel directly into the throat of the carburettor on acceleration, this is usually the problem with these, it is very fine, dont attempt to poke anything down it, use a quality carburettor cleaner with the straw attached, feed cleaner from the bottom of the main carburettor housing, this should when clear fire a jet of carb cleaner from the nozzle in the throat, if not blow compressed air through afterwards, then do the same from the nozzle end, trying to dislodge any grit blocking the fine passage. If you fail to get a clear jet put the carburettor back in the ultrasonic and then repeat this process, the engine will not run properly whilst this jet is blocked.
Once the nozzle is cleared on all 3 Carburettors, check the Carburettor Bowl Assembly on each carb, this has the small pump on the side which forces fuel up through the nozzle, with a small puddle of liquid carb cleaner in the bowl of the carb, ensuring you are wearing safety protection and pointing away from the eyes. press the silver round plunger on the side of the bowl, this should squirt fuel up which when assembled would squirt through the nozzles you just cleaned.
As long as everything above is clear, clean all other parts of the carbs, re assemble and follow the manufacturers service manual to fit and balance the carbs, we find a Carbtune PRO off ebay works perfect.
We sell Yamaha Gaskets, Carburettor Cleaner, Workshop Service Manuals and Service Kits.