Outboard shuts off as ball gets very soft

[bassmasterrap]

I was out yesterday cruising for about 10 min then the power died off a lot. couldnt get it more than 2000k rpm then it started to shake and shut off. Looked and noticed the fuel ball was very soft and no gas in it. I pumped it a little and would turn on thn die with the same problem about a min later. Luckily I had a 3 gallon auxillary tank. Once i hooked it up no problems. Is there a seperate filter inside of the gas tank? A screen of some sort? All hoses look fine. BTW its a 1980 mercury 175

 

[seasick]

First thing to check is the tank vent. If blocked, fuel will stop pumping. To do a quick check, open the gas filler cap when the problem occurs. If the problems goes away, your vent is blocked or the vent tube is blocked.
There is no filter usually in the fuel tank. You could have a clogged pick up tube (there may be a screen over it), a bad anti-siphon valve or fairly common, a colapsed fuel line hose. The latter is more likely if the fuel lines are old and often there is no external signs that the hose is bad.

 

[ocnslr]

Your 'bulb' should be between the installed fuel-water separator and the engine. So, if the engine is having trouble pulling fuel from the main tank, then the filter in that separator assembly would also be a probable cause.

When you shifted to the small auxiliary tank, you bypassed that large separator assembly as well.

If you don't have a fuel-water separator/filter assembly installed, then I recommend you add one.

Brian

 

[gradyfish22]

Check fuel lines and filters first. If the filters are new and no water is present then its possible you got air in the line, improperly changing tanks or a collapsed line could be the cause, if that is not it, then its possible your fuel pumps have gone, they will act similar to how you mentioned, if you pump the ball as it does it, does it jump up a little in rpm but not get up to speed? If so I would lean that way, but check the simpler stuff out first and try and troubleshoot it yourself, fuel system lines should be checked every year anyways so it doesn't hurt to check them yourself anyways before thinking it could be the pumps.