79 Evinrude 70 HP Leaks Fuel Out of Carbs While Running, Wont Start Warm

gobbleme

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Jul 13, 2017
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I've got a 1979 Evinrude 70 Hp motor. It generally runs very well. It always starts cold with no issues, and if it's been running and it's nice and hot it also starts no problem. If it has been running for a while, and then you let it cool down so it's "warm" (for example drive out to your fishing spot, and stop and anchor for an hour or 2) it won't start at all. No combination of choke and throttle seem to make a difference. All you can do is wait several more hours and try and cold start it, and then it will start and run like nothing was wrong. I have also had difficulty replicating this in my yard; it only seems to be a problem when it's gotten nice and hot under load, and then will leave me stranded on the water lol. I noticed that while it is running it leaks fuel out of the intake side of the carbs. I rebuilt the carbs and put a carb-kit in but they still leak fuel. It only leaks out while the engine is running (or cranking), and it keeps good pressure on the fuel line (primer bulb) while not running so I don't think the issue is with the float bowls. Did I not clean the carbs well enough when I took them apart? Any idea if this is what is causing my starting issues? Any ideas on either would be appreciated.
 
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fireman57

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Aug 24, 2004
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The leak is probably caused by your float not being set correctly. It could also be something in a reed valve making them spit fuel but the possibility that all three have something blocking them is nil. Make sure it is level when the carb is turned upside down. The not starting could be a powerpack or other ignition part that breaks down when it gets hot. When they cool then they "reset' and work again.
 

gobbleme

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Jul 13, 2017
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The leak is probably caused by your float not being set correctly. It could also be something in a reed valve making them spit fuel but the possibility that all three have something blocking them is nil. Make sure it is level when the carb is turned upside down. The not starting could be a powerpack or other ignition part that breaks down when it gets hot. When they cool then they "reset' and work again.


Ok, thanks for the ideas. I'll pull the carbs and check the float levels. I don't think I set them when I put the new floats from the carb kit. As for the power pack/ignition thing, do the power packs commonly go? I was going to start with replacing it and the ignition coils, but they're expensive parts to only maybe solve my problem... Gotta love an intermittent issue haha.
 

fireman57

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Aug 24, 2004
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coils are cheaper than a pack. cdi has a website to troubleshoot ignition problems but require an expensive dva meter
 
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