Jet pumps again

jetsled1 · 12-09-2002, 05:56 PM

Ok I am confused,
Those that know me would say "what�s new", but any ways.

I have a 2003 merc 115 with a "new" style jet
It has a flanged liner that fits between the shoe and pump housing and an aluminum impeller. I have an old style jet on the boat I am replacing, that I have flowed and tuned, sharpened the grates on the shoe etc... I wanted to try the flowed shoe against the new one but obviously they won't interchange. Has anyone done any flow testing with the new style shoes, making the transition smoother to the liner, grate sharpening etc. it seams that with the new style it would be more difficult due to the liner not being bolted in like the old style. The liner is loose in the shoe until you bolt it together.
So what do you all do, just run it like it is, (now what fun would that be). The boat runs between 45-47 mph flat out now, but if I could only get another 5 mph I could hit fifty......

FEAR NO FISH! · 12-09-2002, 07:44 PM

You don't need to go that fast. I put my boat on the rocks one early morning in the Hanford Reach this year. I was going over 50 when I noticed rocks out of the corner of my eye on the starboard side. I knew that was not a good thing as I was on the left side of the river. 30 can be too fast. Be careful out there and learn from others mistakes.

Thumper · 12-09-2002, 08:37 PM

I used to sharpen my shoe grate. Then I noticed that I picked up rocks much more since they tend to get wedged more easily. No more sharpening for me.

onstep · 12-10-2002, 07:17 AM

On in-line motors 3 cylinders (i.e. your 60,75,90's) blueprinting and stainless implellars have shown to decrease performance. You won't see any performance increase with a stainless impellar on your 115. What you will have is a more durable impellar. I don't believe blueprinting will offer any large increases. Talk to San Leandro Outboard Jets (manufacturer) or Stevens (dealer) they did the testing on this. I couldn't tell you the exact physics.