# Inline fuel filter question



## fish2day (Apr 9, 2011)

I have a 1991 Johnson 200hp that has appeared to be starving for fuel. I thought the main tank might be the problem, so I replaced the inline fuel filter with a clear glass filter so that I could see the gas. I then hooked up a 12 gallon portable tank to bypass the main tank.
The inline fuel filter will only stay about 1/4th full when the engine is running. I pumped the primer bub and I cannot get the inline filter to get completely full. 
How full should the inline filter be when the engine is running?? Is this normal?? What could the problem be?? Any help appreciated.


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## Kingfish514 (Jan 21, 2009)

On my boat the big problem was the fuel lines being gummed due to ethenol. I would remove check the hoses as you might have the same problem. remove the connector at the engine and look in the line and see if you have "varnish" I was able to use a phillips head to scrap some out, I ended up replacing lines, bulbs and then installed a fuel/water seperator and so far so good. If you do find the gunk you may need to think about your carbs being rebuilt?? Not a mechanic but a life long boater


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## 20simmons sea skiff (Aug 20, 2010)

ive had race cars that filter does same. My manuals say to only use an inline filter up to around 70 hp and to run a racor or other marine filter for larger motors. Heck my friends boat had twin 427 cobra iron block motors, 69 model, filters dont stay full on his boat neither


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## 20simmons sea skiff (Aug 20, 2010)

yea, they say all older motors need to be up graded to new fuel line.All my reading says to use automative line since it is made for achol fuel


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## X-Shark (Oct 3, 2007)

> All my reading says to use automative line since it is made for achol fuel


No, you use the ethanol approved "Marine" fuel line Type A1.



> New ethanol compliant Fuel Feed and Vent hose is a Fire/Alcohol resistant tube which resists permeation of alcohol-enhanced gasoline. 368 Series hose has improved synthetic layers to limit permeation. It is reinforced to comply with latest EPA and CARB low permeation requirements. Maximum continuous length is 50 ft.


http://www.jamestowndistributors.co...76&familyName=Fuel+Feed+and+Vent+Hose+Type+A1

You can get it at Rubber & Specialties in town.


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## fish2day (Apr 9, 2011)

Thanks for your help. Will start by replacing fuel lines,,,,can't hurt for sure..


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## lastcast (Oct 12, 2007)

Rick, when you say you changed the inline filter, do you mean the one under the cowling or fuel/water seperator? You should have both.


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## pappastratos (Oct 9, 2007)

20simmons sea skiff said:


> ive had race cars that filter does same. My manuals say to only use an inline filter up to around 70 hp and to run a racor or other marine filter for larger motors. Heck my friends boat had twin 427 cobra iron block motors, 69 model, filters dont stay full on his boat neither


 Hey, I ran one of those clear glass filters along with a seperator on a 1997 gas guzzling E-rude 200 w/o any problems !


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## lastcast (Oct 12, 2007)

Might want to try something before you start replacing the lines. Take the input fuel line off the VRO, use the new fuel line and an external tank to see if it changes anything. It might rule out half of your system.


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## fish2day (Apr 9, 2011)

lastcast said:


> Rick, when you say you changed the inline filter, do you mean the one under the cowling or fuel/water seperator? You should have both.


Yes, I did change both the seperator and the inline fuel filter. Thanks for your input. I'm now checking my high speed jets in my carbs to make sure they are not stopped up. I'm also trying it on a portable tank this weekend to bypass the main tank.


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