Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Boston whaler montauk 17 max engine
Posted by Jorden Dovianus on 05/07/13 - 8:25 AM
#1
Dear Whaler fans,
I own a 1980 Boston whaler Montauk 17ft and I was thinking about a 140 Yamaha V4 engine in stead of the 85 Yamaha I have now. I have seen people put 300HP behind the boat but do you think 140 is possible? Thanks for the comment.....
Posted by Tom W Clark on 05/07/13 - 8:39 AM
#2
The Montauk is rated for a maximum of 100 HP. I have seen this hull powered with as large a motor as a 175 HP V-6. I doubt anybody have ever put a 300 on one.
140 HP? I wouldn't, but it has been done. Not particularly unusual.
Posted by CES on 05/07/13 - 8:42 AM
#3
A 300???? I'd like to see a picture of that happening.
Posted by Windknotz on 05/07/13 - 8:59 AM
#5
I hava a Yamaha F115 on the back of my Montauk, and it gives me all I'll ever need. I would think a 140 would be scary if not set up right.
Posted by Tom W Clark on 05/07/13 - 9:00 AM
#6
That's a 300 decal all right, but the only 300 HP two stroke Yamaha ever made as the 300 HPDI.
The Montauk takes a 20" shaft length motor, just like the motor in the video.
The 300 HPDI was made in only one shaft length: 25"
Posted by CES on 05/07/13 - 9:09 AM
#7
I'm with Tom on this one.....anyone can buy a set of Decals and stick 'em on there and call it whatever they want too.
I'm calling foul on this one.
Posted by wing15601 on 05/07/13 - 9:25 AM
#8
And the decal is kind of off center.
Posted by Barry Bicknell on 05/07/13 - 9:25 AM
#9
If this is not a 300 HPDI Yamaha ((?), then what cowling is that where the 300 HP decal was placed over....looks like a HPDI cowling to me. Also, take a second look at the shaft specs for the Yamaha 300 HPDI showing a shaft length of 20" ? It could all be a hoax, maybe?
http://www.yamahaoutboards.com/outboards/2-Stroke-HPDI/specifications
Back to Jordan's question as to a 140HP V4 mounted on his 17' BW Montauk, it's not rated for over 100 HP, insurance will be a tough placement, it is Not necessary, BUT, it's been done! Please be careful of yourself and other boaters!
Edited by Barry Bicknell on 05/07/13 - 9:35 AM
Posted by EJO on 05/07/13 - 9:56 AM
#10
Hey I belive these crazy Dutchman. They show once that they are going 52 mph but he mentioned he made it to 62 mph. While filming the helmsman does mention that he has a lot of throttle left and he can't use it as the boat rolls (see different thread started by Duf) and it really started to porpoise. They were also excited as how easy it was to get up on plane without much throttle.
I can see maybe a 10-20% over power based on weight (i.e. an 115HP) but the 140hp asked about or in the case of the youtube vid 300hp are crazy dangerous and only good for drag racing.
Posted by Tom W Clark on 05/07/13 - 9:58 AM
#11
...take a second look at the shaft specs for the Yamaha 300 HPDI showing a shaft length of 20"?
I have.
It could all be a hoax, maybe?
Could be.
Posted by Jorden Dovianus on 05/07/13 - 1:26 PM
#12
Thanks for all the comments guys! So I think I would have to stick with max 115hp! Just for safety! Haha! I dont think the 300 is a hoax! Dutch people are crazy!
Posted by contender250 on 05/07/13 - 1:55 PM
#14
Jorden; I have an older 1975 16'7" Boston Whaler, I have a 1985 140 Evinrude Looper that I purchase new and installed it on the whaler. I just redid the Whaler last year for the 1st time. I have own this boat since it was 6 months old. The boat handles very well I usually run around at 1/2 the throttle, I have a custom 34 gallon fuel tank . I did away with the VRO and mix my oil and gas (NEVER A PROBLEM) If this engine ever blows I will be replacing it with the same thing. I have never question or have been sorry for the 140 and would do it again. Best engine I have ever owned also....Good luck
Posted by Snook master on 05/07/13 - 2:11 PM
#15
Windknotz wrote:
I hava a Yamaha F115 on the back of my Montauk, and it gives me all I'll ever need. I would think a 140 would be scary if not set up right.
What's your top speed and fuel burn at cruise with that F115? I have a 2003 Yamaha 130hp on my Montauk and was thinking about selling my engine and going with a F90 or a F115.
Posted by Jeff on 05/07/13 - 2:30 PM
#17
[b]Tom W Clark wrote:
The Montauk takes a 20" shaft length motor, just like the motor in the video.
The 300 HPDI was made in only one shaft length: 25"
Are you sure the motor in the video is a 20" shaft? With the huge spray coming from the motor and the deep hole it is creating in the wake, it could be a 25" shaft motor.
For the good of all viewers, the video's poster should done a been job documenting and detailing the set up.....but you get what you pay for, and youtube is free.
Either way, it sure looks like the pilot is fighting a hard "Whaler Roll" with the hull keeling over to port....
Edited by Jeff on 05/07/13 - 2:40 PM
Posted by Jorden Dovianus on 05/07/13 - 2:46 PM
#18
Ooooh... I'm still confused! I dont want to be dissapointed when i install the 115 so still thinking about the 140 v4.... The 85 Yamaha only runs 50km per hour! To slow for the Montauk....
Posted by DennisVollrath on 05/07/13 - 2:54 PM
#19
Jorden,
Something else is not right if an 85hp motor is only pushing your boat 50km/h. A 70hp gets my Montauk to 57km/h.
You might want to dig a bit further.
Dennis
Posted by jamesgt727 on 05/07/13 - 7:50 PM
#20
If performance is your concern, you should consider a Mercury 115 Pro XS for that hull. It's a two stroke, but it's lighter and its a factory hot rod motor thats rated at 123 HP I think.
I saw that video, peak speed on that cell showed 82 Km/h (51 mph)? I would have expected 169 km/h with the right prop.
Posted by Tom W Clark on 05/07/13 - 9:40 PM
#21
A 90 HP outboard on a classic Montauk is good for 42-44 MPH (69 KPH). 100 HP is good for about 46 MPH (74 KPH). 115 HP is good for about 50 MPH (80 KPH).
How fast do you want to go?
Posted by Petrus on 05/08/13 - 12:47 AM
#22
I've driven a Montauk 17 with 115hp 4-stroke, and no problem at all to handle. I would guess a 140 would work just fine.
Howcome the Montauk 17 is "that slow". I used to have a 800 pounds center console v-hull (18 degrees) which made 42 mph with 60hp 2-stroke Mariner alu propeller. It also pulled a 160 pounds water skier out of the water on one ski.
If the Montauk weighs 900 pounds , sholdn't it be capable of at least 46mph with a 90hp?
By the way, I know that boat handles a 140hp 2-stroke.
Edited by Petrus on 05/08/13 - 12:48 AM
Posted by Jorden Dovianus on 05/08/13 - 12:55 PM
#23
Is it possible to put an xl tail on The Montauk? Thanks!
Posted by Tom W Clark on 05/08/13 - 1:29 PM
#24
xl tail? What is that?
Posted by Jorden Dovianus on 05/08/13 - 2:25 PM
#25
The length of The engine tail....
Posted by Tom W Clark on 05/08/13 - 2:47 PM
#26
engine tail? Do you mean the shaft length? Can you put an Extra Long XL (25") shaft length motor on a Montauk?
No. the Montauk needs a Long L (20") shaft length motor