7.5 Chrysler Sea King will not stay running.

[dave6982]

Hello,

I am new to this site and was hoping someone could help me out. I have a 7.5Chrysler. I have only had it for about a month. It is between a 79 - 84. I am missing one # on the vin plate to find the right year. The motor ran great the first 2 days I had it than I had trouble getting it to start and once it did I couldn’t get it to idle. So I took it back to the guy I bought it from and he cleaned out the carb and did a few other things to it. I took it out 2 weeks ago after he fixed it and it ran like a champ. Idled great and all. Than I took it out again this Saturday and it ran great for about 8 hours. Than it just stalled. I tried to restart it and it didn’t want to. Just kept stalling. I let it sit for a few thinking maybe it over heated. After about 15 minutes it ran for a while than stalled again. This time I let it sit for a half hour. Than it ran great for 3 miles. I ran the gas out of it and took it home. Next day I took it out and it was back to stalling again. This time it was stalling right after I would get it running. Once I got it started I drove it about a mile than it stalled as soon as I got it just above Idling speed. It done this for about 2 hours than I decided to just bring it in. So far we just replaced the spark plugs. Any idea what this could be.

Thanks
Dave

[jakeyman_i_am]

Are you positive that it is moving water through the water pump? When my 15 hp was doing this it was because my water pump housing was pited and it not moving enough water to cool.. It would get me about 1-300 yards from the boat landing then die.. After 15 minutes it would fire right back up and do it again..

When it died it felt like it ran out of gas (sounded "boggy" before dying)

[dave6982]

The water is pumping out pretty good. I will double check it again. But when i was running it did sound like it was running out of gas and would bog down and cut off. Once this issue happened to you did you have trouble restarting it.

[jakeyman_i_am]

The water is pumping out pretty good. I will double check it again. But when i was running it did sound like it was running out of gas and would bog down and cut off. Once this issue happened to you did you have trouble restarting it.

Sorry for the slow response. Yes, it would have to sit for 10-15 minutes before it would run again, regardless of what I did (pumping fuel ball, starting fluid, etc.) After replacing my water pump and housing, it pumps water great.

Maybe your fuel diaphragm? If it is equipped like mine, the little rubber fuel pump is to be replaced if it is stretched or discolored, but you may want to verify that with someone who knows more, or a service manual, before you spend any money.. I have done that to my motor too, and it improved its starting and high speed performance. They are generally cheep and easy to replace.