Evinrude 40973R 40HP Selectric Shift - Slipping or Spun Prop Diagnostics

[stevepamboukes]

Thanks for chiming in oldboat1

Right, if I installed the extended leg (yes it comes with the longshaft... otherwise how would it work?), I would bring the transom height back up to where it was for a net lowering of about 2". I bought the kit cause the price was right, don't necessarily need to use it. I just don't wanna hack my transom anymore then I have.

So you're saying ATF is a good substitute for LU oil? Seems kinda thin. Along those same lines, though, I'm just using conventional Type C LU oil and will put the good stuff in after I've replaced some seals and done any necessary repairs.

I have replaced the impeller, not a lot of hours on it for sure. I suppose the thermostat is fairly accessible....

Thanks for checking me on the water flow out of port on leg... It didn't seem like a lot of water to me at first.

Fortunately I don't run in reverse a whole lot... so I may keep my snorkel on! Haha I'm attached to it now cause I like how much water I'm getting pumped thru the system. It seems to provide an improvement. Maybe i'll revert to stock eventually.

I have checked compression, and I cleaned and gapped points last year. Going "by ear" and feel, the engine sounds like its running just fine. I dont seem to have any lack of power. The engine spools up just like it should. The problem is that, though the engine revs up, my travel speed does not increase. I'm wondering if this is partially from the negative trim angle? As I keep making thrust, it pushes the bow further into the water producing more drag, so even though my engine is revving up and I'm making more power, its wasted in drag....?

 

[oldboat1]

Think it's the negative trim. And....drag from that snorkel. May need to modify it before applying for a patent!

[edit. Might drill some holes in the transom (outside, near the bottom). If you get water, maybe smelly water, assume you have some extra weight. Solution is to open the flooring and pull out saturated foam.]

 

[stevepamboukes]

Haha ok so I'm not going to be a staunch defender of that snorkel.... but its a pretty favorable drag profile... I don't see that contributing much to performance... plus I've had this issue since before the snorkel (its a brand new mod), so that isn't killing me.

I've had the whole deck out when I rebuilt the frame... there's no foam down in there, no water (anymore). I didn't attack the transom so yes that is likely waterlogged, but the rest of the boat is dry.

I keep my 6 gallon gas tank up in the bow. I used to keep a 15gallon tank in the stern... that seemed like way too much weight, so I switched over to the smaller tank in the bow this year, hoping to even up the trim a bit.