Fuel Lines/Performance

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Cadet
Joined
Jun 16, 2003
Messages
23
I had a rebuilt '85 Johnson 175 V6 put on my boat. The mechanic used my current fuel lines that are 5/16". He told me I would need to replace the fuel lines with 3/8" lines. The engine is set up for 3/8 lines. <br /><br />1)Would the 3/8" lines make a difference in the performance of the engine?<br /><br />Right now I am turning 5000 rpm at wot and getting about 46 mph with a full tank to half tank of gas and just myself on board. The boat is an 1990 18' Cobia. Weight is about 1300 pounds not including gas. Have a 35 gal. gas tank, not sure how much the gas weighs. I have a 15x21 prop.<br /><br />2)Is this as fast as I should get or should I get more speed? With my old 1990 100hp Merc I got about 38 mph under the same conditions.<br /><br />Any advice is greatly appreciated<br />Thanks,<br />Barry
 
D

DJ

Guest
Re: Fuel Lines/Performance

ALL V-4's and V-6's REQUIRE 3/8" lines.<br /><br />You may not notice a performance loss, however, you DO NOT want to even risk starving the engine for fuel. It will melt down.
 

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Cadet
Joined
Jun 16, 2003
Messages
23
Re: Fuel Lines/Performance

Thank you for your wisdom and quick reply Djohns19. You probably have saved my second engine. Will replace with correct 3/8" fuel lines tomorrow.<br /><br />Barry
 
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