I have an Evinrude 4hp 2 stroke that won't start. Has spark on both cylinders. seems to have compression. Have cleaned the carb, though jets were loose, don't know jet settings. Petrol is clean and flowing to float chamber, all fuel lines seem clear; fuel is from gravity tank on engine. Had it running for about 30 seconds after many pulls of cord, but died out and won't restart. Have repeated carb clean and fuel line checks. Can anybody advise please?
Sorry JB, can't find jet info. Situation so far,, tried new clean fuel and new plugs NGK BRH6S compatible to Champion QL77JC4 as far as my local supplier can ID. Still won't fire! Purchased a manual, lots to read. Sprayed fuel and even Bradex Easy Start direct into carb, still won't fire. Definitely getting fuel through. Can anybody advise setting / position for main jet and pilot screw, accessed from float bowl? Gather from manual this engine is fixed timing, electronic ignition, so no points etc. Engine has run for a few seconds previously, so presume it's not a timing issue; but can't get anything now. Rebuilt a few 2 strokes over the years, never had this amount of reluctance to start unless timing was way off or crank bent. Fuel is burning, checked by positioning plugs just outside holes, can get flash or flame depending on setting of main jet, bit of a severe test! Grateful for any further advice before I start major strip down. Thanks, Shep
"Adjusting carbs" in TD's "Top Secret File" Pinned in second place at the top of the "Johnson and Evinrude Outboards" index.
Several other items there that may be worth reading.
BZ7HS-10 are the NGK equivalent plugs but BR6.... is one grade hotter and is resistively not inductively suppressed. Use the inductively suppressed plugs, the Champion "Q" ones or the NGK "Z" ones, with CD ignition not the resistive suppressed "R" ones. Wont explain your no start though.
Don't use starting fluid ... no oil ... spray fuel mix instead.
You only have an idle mixture adjustment . Prominent position above the air intake.. but I think you have to remove a plug from the air silencer to get at it. Main jet not adjustable! Nothing to adjust in the float bowl apart from checking float level.
Check sparks. Check compression.
Possible that flywheel key has sheared and put the timing out but would only be likely to occur if run without the nut being correctly torqued