1987 Montauk 17 E-TEC 90
Posted: Thu Aug 24, 2017 10:04 am
Hi everyone. I recently bought a 1987 Montauk with a 2014-year-of-production E-TEC 90. I've looked at the forum over the past few years but just recently registered and this is my first post.
The E-TEC 90 on my boat is a used motor with about 500 hours. It runs great but I think it may be propped incorrectly. Currently the E-TEC 90 has a 17 VIPER propeller. It accelerates like crazy but seems to lack a little on the top end and generally runs at an engine speed that is too high for the boat speed.
For example, I get 25-MPH boat speed at 4,000-RPM engine speed; and 35-MPH at 5,700-RPM at full throttle. I believe 5,700-RPM is a bit outside the recommended range for this engine.
I don't generally run that fast. (Actually the one time I ran WOT with only me on the boat I blew the main engine fuse--not sure if that is related.) I prefer to run about 3,500-RPM but currently that is only about 20-MPH boat speed.
The E-TEC 90 is mounted on an aluminum setback plate with the A-V plate about 2.5 to 3-inches above the bottom of the hull. The setback plate was not my doing and I'm debating removing it this winter. I don't know how much role this may be playing in the performance characteristics.
I'm quite familiar with the following page:
http://continuouswave.com/ubb/Forum4/HTML/004278.html
which offers an excellent comparison of propellers. For whatever reason my performance does not seem to match up.
Do you guys recommend going up in pitch to say a 19 VIPER?
Or, considering another 17-pitch propeller, that may perform better when pushing a Montauk?
Thanks for any advice.
The E-TEC 90 on my boat is a used motor with about 500 hours. It runs great but I think it may be propped incorrectly. Currently the E-TEC 90 has a 17 VIPER propeller. It accelerates like crazy but seems to lack a little on the top end and generally runs at an engine speed that is too high for the boat speed.
For example, I get 25-MPH boat speed at 4,000-RPM engine speed; and 35-MPH at 5,700-RPM at full throttle. I believe 5,700-RPM is a bit outside the recommended range for this engine.
I don't generally run that fast. (Actually the one time I ran WOT with only me on the boat I blew the main engine fuse--not sure if that is related.) I prefer to run about 3,500-RPM but currently that is only about 20-MPH boat speed.
The E-TEC 90 is mounted on an aluminum setback plate with the A-V plate about 2.5 to 3-inches above the bottom of the hull. The setback plate was not my doing and I'm debating removing it this winter. I don't know how much role this may be playing in the performance characteristics.
I'm quite familiar with the following page:
http://continuouswave.com/ubb/Forum4/HTML/004278.html
which offers an excellent comparison of propellers. For whatever reason my performance does not seem to match up.
Do you guys recommend going up in pitch to say a 19 VIPER?
Or, considering another 17-pitch propeller, that may perform better when pushing a Montauk?
Thanks for any advice.