1978 Johnson Javelin 85HP cold starts

[lionhead]

My 1978 Johnson 85hp (Model# 85ETLR78C Serial # J8004158) does not want to run properly on cold starts. I need to constantly use the choke to keep the motor running. It starts and revs to about 1500 RPM and then will slowly die.Choking when RPM hits 1000 keeps the engine running and RPM goes back up to about 1500 - 1800. I may need to choke the engine on a hot day 10 -12 times before it will run without stalling. No other problems at all.<br />Carbs repaired with new floats and needles.

 

[fireman 757]

Re: 1978 Johnson Javelin 85HP cold starts

Your fuel pump might be weak and not working properly at low rpm. rebuild it. It is a simple operation.

 

[Ross J]

Re: 1978 Johnson Javelin 85HP cold starts

Mine's a Johnson Javelin as well and I had the same or similar problems. I found it went away after I replaced the spark plugs and changed to Penzoil oil. I know it sounds like an advert but it worked for me without any other problems.<br />Ross

 

[Dhadley]

Re: 1978 Johnson Javelin 85HP cold starts

From your post I gather once the motor is warm it's OK. If so I think we can rule out the fuel pump. It should misbehave cold or warm. <br /><br />What fuel are you running? Make sure it's FRESH 87 octane. Spark plugs should be Champion (Q)L77JC4 or similar Champion plug. If you are running a higher octane or fuel older than 30 days with another brand of plug it may have something to do with the slow warm up process. <br /><br />Also make sure you are running thermostats. <br /><br />Good luck!