Suzuki DT85 Cutting Out

[Vulcan77]

A follow up, after more investigation, to my earlier post regarding a 6m speedboat with a Suzuki DT85 (85HP) 8501 Outboard circa 1994.<br /><br />When cold, it starts OK with full choke but after a few minutes of gradually reducing choke it can cough and cut out. Restarts ok but can repeatedly cut out when leaving the jetty at slow speed. Outside the harbour at speed and gurgling it runs ok.<br /><br />After anchoring and switching off, it's harder to start. The spark plugs are oiled up so need cleaning but even then seems to need full choke to start. I'm told that the compression test was ok.<br /><br />I have serviced the fuel line including the fuel pump so carburettor strip-down is next. Before I do this any suggestions gratefully received.<br /><br />I have rebuilt classic cars but boating is a new challenge for me. I'm not to keen on engine problems out to sea!

 

[jim dozier]

Re: Suzuki DT85 Cutting Out

Your description of the engine improvement with the use of the choke suggests that the engine is running lean. The usual cause for this would be dirty carb jets. Remove the 3 carbs and do a thorough cleaning and rebuild installing the parts from a rebuild kit (new float valve and gaskets). Check the setting on the float valve when you reinstall it. Clean the orifices (main jets, idle air orifices, transfer jets) with carb cleaner and compressed air and reinstall the carbs with new gaskets. Reset the idle mixture screw according to the specs (unscrewing it leans out the idle mixture). Check the synchronization of the throttle butterflies with the ignition advance link. If you haven't got one by now go to the bottom of this web page and get a manual for the specs. You should be good to go.