Driving me crazy.....

[Betterthannothin]

Ok, 1986 or 87 merc 75hp ser. no. 0a953815. I rebuilt the carbs, and reinstalled, boat ran fine. I replaced the fuel pump diaphram, and now it wont stay running. I prime it, it runs off what is in the bowls then dies out.
Is there something common I might have missed?

 

[starkyb]

Re: Driving me crazy.....

It sounds like there could be some air getting in the system somewhere. Check all of your lines for cracks. I had a problem similar to that on an 9.8 Mercury and turns out that the check valves inside the fuel pump were bad. Just some places to start.

 

[Mi duckdown]

Re: Driving me crazy.....

Check float level, for proper height setting.
Plus what starkyb stated.
Sorry did not catch the part about motor running fine after carb rebuild.

 

[Betterthannothin]

Re: Driving me crazy.....

Is there a way to test the check valves or should I just replace them?

 

[Betterthannothin]

Re: Driving me crazy.....

Ok, I took a look at the check valves and one of them was crushed on one side, keeping it jammed shut. I was able to rework it so it now works fine. Thanks for the help!

 

[j_martin]

Re: Driving me crazy.....

One of the hardest things to teach engineering personnel is this fact:

If you walk up to a running machine, do something to it, and it now doesn't run......


IT'S WHAT YOU DID