75 chrysler runs 30 mins at a time

[lwaun]

I have recently aquired a 1978 bayliner with a 75 chrysler outboard I have replaced plugs, fuel filter, ignition coil & even the starter. I can start it up no problems but runs for almost exactly 30 minutes then it stahls and won't restart till after about an hour and again runs 30 minutes and stahls. I had tried both going fast or slow the 30 minute thing seems the constant. Any help would be much appreciated. I have read similar threads and tried some of those ideas also.

 

[wickware]

Re: 75 chrysler runs 30 mins at a time

Does your over heating alarm etc work? Suggestions:
1. Please check for over heating
2. Check for swelling fuel lines or deteriorating restricting fuel flow
3. Check for fuel vacuum due to not enough venting.

JOW

 

[huskerdaninva]

Re: 75 chrysler runs 30 mins at a time

Vent open on the fuel tank? Or maybe not quite closed all the way and creates a vacuum issue after a few minutes, shut off for a few minutes perhaps is enough time for the vacuum to break in the tank/lines and she'll start back up and repeat the process? I don't know, just a thought and perhaps something simple to check. Good luck...

 

[lwaun]

Re: 75 chrysler runs 30 mins at a time

thank you both. Tried 2 different fuel tanks.Fuel lines are good. Not sure about the overheating or alarm though. I'll check that .