Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: 17 montauk with 90 etec. PROP help
Posted by Alexh0616 on 05/08/18 - 6:23 PM
#1
Im about to buy a new 4 blade prop for my 90 etec sitting on a 1986 17 montauk. Anyone out there running a 4 blade and if so which prop. Thank you. Alex
Posted by Phil T on 05/09/18 - 6:18 AM
#2
Given the low end torque of the E-TEC 90, few owners have installed a 4 bladed prop on a classic Montauk 17.
Why 4 instead of 3 blades?
What are you trying to accomplish that your current setup (please describe mounting height, prop manufacturer, model and size) is failing to achieve?
Posted by Alexh0616 on 05/09/18 - 9:01 AM
#3
I just put a new 3 blade viper ss 17 pitch on it and it runs great. Wot calm conditions i was running 44mph. That was with me and another person, cooler, full 12 gallon tank and all the fishing gear. I have the motor on a micro jack plate and sitting on the second hole. It likes to be jacked all the way up and trimmed out alittle i get best water pressure. I was thinking of going all the way up to the last hole. I mainly run the flats just looking for a little better hole shot . dont get me wrong it jumps and goes good now im just looking for that little more and a good cruising speed at low rpm.
Posted by Phil T on 05/09/18 - 9:32 AM
#4
Alex -
The 13-7/8" x 17" BRP Viper is a good choice for the engine.
Typically ETEC motors like to be mounted three holes up (all the way) when attached to the transom depending on prop choice.
With a setback bracket, you will want to go a bit higher. Typically, add 1" of rise for every 12" of setback
How many inches above the keel is the anti-cavitation plate? Use a straight edge and measure with the engine vertical (trim out slightly).
Posted by Alexh0616 on 05/09/18 - 9:50 AM
#5
Hey phil thanks for all the info so far. Ill have to check that tomorrow and get back to you. Thanks again
Posted by action on 05/09/18 - 12:04 PM
#6
I use a Viper 13" pitch on my 1988 Montauk with ETEC 90 and it seems like a very nice combination.
Posted by Alexh0616 on 05/11/18 - 11:44 AM
#7
Hey phil so the cavitation plate is 5 inches about the keel
Posted by Finnegan on 05/11/18 - 7:47 PM
#8
If the engine is really mounted directly on the transom, 5" above the keel is in the realm of high performance all out racing and special low water pickups. With only four bolt holes of height settings, I can't even see how you achieved that height. Fpur bolt pattern holes in an outboard engine bracket will only allow a max height of 2.25 inches, which is the maximum height you should be running a pleasure boat like a Montauk.
On my Montauk with a much more powerful and faster Merc 115 "tower", I only have the engine anti-ventilation plate set up 1-1/2" above the keel, and that is plenty high for a Laser II performance SS prop.
Posted by sraab928 on 05/12/18 - 3:53 AM
#9
Finnegan wrote:
If the engine is really mounted directly on the transom, 5" above the keel is in the realm of high performance all out racing and special low water pickups. With only four bolt holes of height settings, I can't even see how you achieved that height. Fpur bolt pattern holes in an outboard engine bracket will only allow a max height of 2.25 inches, which is the maximum height you should be running a pleasure boat like a Montauk.
On my Montauk with a much more powerful and faster Merc 115 "tower", I only have the engine anti-ventilation plate set up 1-1/2" above the keel, and that is plenty high for a Laser II performance SS prop.
Check out his second post - here is the relevant info
"I have the motor on a micro jack plate and sitting on the second hole. It likes to be jacked all the way up and trimmed out alittle"
Posted by MG56 on 05/12/18 - 8:33 AM
#10
sraab928 wrote:
Check out his second post - here is the relevant info "I have the motor on a micro jack plate and sitting on the second hole. It likes to be jacked all the way up and trimmed out alittle"
Ha, thanks for pointing that out, I was beginning to wonder when they started selling Etec 90's with a short shaft..