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Mod40yammy
07-16-2014, 07:46 AM
I am in the process of rebuilding a 1999 Yamaha 40 2-stroke 3 cylinder and I am wanting to remove the oil injection system. Are there anything in particular that I should be aware of in doing so??? Should be an easy removal correct??? Any tips or tricks would be greatly appreciated.

Koondog
07-23-2014, 03:52 AM
Remove the pump and worm gear. Fabricate a cover plate and gasket. I use 3/16" aluminum plate. Secure the plate with two m6 x 1.0 x 20mm bolts. Seal the oil injection ports on the intake. I punch out the stainless tubes and fill the entire hole with epoxy like JB Weld.

Mod40yammy
07-23-2014, 07:28 AM
Koondog..... Thanks for the info!!! That's what I was thinking also, I just wanted to hear how others may have tackled the situation. I've gotten it removed, I just have to fab a cover where the oil pump was at.

Fast Fred
07-24-2014, 09:36 AM
removing the worm-gear opens a lot of space inside the case, witch drops the charge pressure, best to make a plastic dowel to take it place.

nhpoplin
07-25-2014, 10:35 AM
hadnt thought about it like that fred. would that significantly drop the crank pressure? I got an idea or two I'm about to test out to bump up the crank pressure in mine. should beef her up on the low end I would imagine

Fast Fred
07-26-2014, 05:06 AM
it doses make a difference, you can feel it when it's runnin.