Fuel inlet hoses under cowling

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Douglasdzaster

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Location
Smithville,Texas
LOCATION
Smithville, Texas
I’ve got a 1992 40 hp Yamaha. I’ve replaced the fuel line with marine grade and installed a separator filter. Now I’m under the cowling and my question is do I need to stick with the OEM parts or is there a way to as far as using hot water to shape the lines myself or any other ideas? While still keeping it safe.
 
Any preformed hoses need to be replaced with the correct OEM hoses. While the OEM hoses are available by all means grab some!
Issues arise when tight bends are attempted with straight hose. Kinked or restricted hoses are the normal result.
There is no good way to heat and bend a straight hose. Also keep in mind heating may separate the inner liner.

Now for the disclaimer.
Years ago OMC used to use a stainless spring inside some of their hoses to keep a tight bend from collapsing.
For my old engines I will sometimes make stainless springs from wire stock and do this. As always, the risk is yours to take.
 
Thanks Pappy, I appreciate the reply and grateful for your advice. This motor has been neglected maintenance wise and I’m big on preventative maintenance. Doesn’t do any good though if I’m not doing it right. Now I’m noticing some fuel coming from the throat of 2 of the carburetors. It looks like I’m not done yet.
 
toss a carb kit in them. The kits come with bowl gaskets. The bowl-to-body joint is sensitive to seeping gaskets, and by now all the original gaskets are long flattened out/shrunken and they rarely seal. This will also cause "flooding". Makes no sense, right? On a lot of Yamaha's the fuel inlet to the carb is in the bowl, there is pressurized fuel that runs up through the bowl and into the main body, where it's then fed to the float valve assembly. If the gasket between the bowl and body leaks, there is nothing to shut the fuel flow off and it will overfill the bowl causing excess fuel usage hard starting and occasionally external leakage.

I don't remember if the old C40 twin cylinder used that style, but if you are updating the entire fuel system, there is no reason not to do the carbs too. Make sure to synchronize them after reinstalling them and check/adjust the timing, idle, pickup, and maximum advance.

One of the carb mounting nuts isn't much fun but not impossible either.
 
Parts are ordered. Except for carburetor kits. It’s a 3 cylinder (40mshq) and kits are $90 each. Got to build my boat account back up a little then they’re next.
 

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