1. Use the full 4 digit year for everything you are asking your question about. Example: 1962, 1988, 2000, 2011
2. Include the correct name of your Whaler model. Example: Montauk 17, Montauk 170, Outrage 26, Outrage 260
3. Include the length when necessary. Example: 16, 17, 18, 20, 22
4. Do not post your email address anywhere on this site as it is already in your user profile.

15SS-Raising Yamaha 70 and new prop?
FlyAU98	#1  Posted on 03/18/12 - 6:46 PM
Member Personal Page Posts: 147 Comments: 1 Joined: 05/22/11	Boat: 1987 15' Super Sport, original with the exception of the battery and gas tank moved under the rear bench seat. Motor is a 1998 Yamaha 70 2-stroke (70ETLG) It seems the recommendation is to have the engine raised a few holes, mine is nearly sitting on the transom right now. Transom Picture Inside Transom Picture Here is how it looks running (about 4000 RPM I'd guess): Running 1 Running 2 When I raise it, should I go all the way to the top? (Hole 4 instead of the currently used Hole 1) Only the top bolts go all the way though the transom and bracket, the bottom bolts seem to terminate inside the bracket. I assume I'll need to change the prop also...the current one is a painted SS prop, with "13x7-K" stamped inside. Prop Picture With just me in the boat it will turn 5700-5800 RPM if I'm lightly loaded, going in the upper 40s. Loaded as I normally use it, 2 adults and a child, plus a cooler and some beach gear, it will turn 5500-5600 RPM. Edited by FlyAU98 on 03/18/12 - 6:50 PM
surfncnow	#2  Posted on 03/18/12 - 8:18 PM
Member Personal Page Posts: 67 Comments: 0 Joined: 05/07/09	It looks like you have 4 bolts holding your engine inside the splash well? I would raise it up another 2 bolt holes and see how many RPMs you turn with your current prop.
FlyAU98	#3  Posted on 03/18/12 - 8:21 PM
Member Personal Page Posts: 147 Comments: 1 Joined: 05/22/11	surfncnow wrote: It looks like you have 4 bolts holding your engine inside the splash well? 4 Bolts-Correct Top 2 go all the way through and have nuts on the outside of the engine bracket. The bottom 2 disappear into the engine bracket.
surfncnow	#4  Posted on 03/18/12 - 10:44 PM
Member Personal Page Posts: 67 Comments: 0 Joined: 05/07/09	Unbolt your engine and move it up 2 bolt holes. See if your lower bolt holes match up with the new holes on your engine bracket. If not, your gonna have to fill and re-drill. Edited by surfncnow on 03/18/12 - 11:17 PM
Whaler27	#5  Posted on 03/19/12 - 4:27 AM
Member Personal Page Posts: 32 Comments: 1 Joined: 10/11/06	It appears that the motor is mounted to the transom using the "blind" holes in the motor mount (the ends of the lower bolts screw into the bracket). This is pretty typical mounting of a Yamaha 70 on a 15 foot hull. To raise the motor on the transom, you will have to drill new lower holes.
Phil T	#6  Posted on 03/19/12 - 8:58 AM
Administrator Personal Page Personal Album Project Albums Posts: 7043 Comments: 6 Joined: 03/26/05	There is a great article by Joe with diagram on how to mount the motor and drill new holes. See the "Articles" section on the left sidebar. 1992 Outrage 17 I 2019 E-TEC 90, Viper 17 2+ 2018 Load Rite Elite 18280096VT
Binkie	#7  Posted on 03/19/12 - 9:42 AM
Member Personal Page Posts: 2012 Comments: 0 Joined: 12/19/05	After you raise the engine you will find that you added some rpms at top end. Before you invest in a new prop, I would have the old one cupped. That will decrease the rpms by 200, and probably add some speed as well.
dgoodhue	#8  Posted on 03/19/12 - 9:54 AM
Member Posts: 278 Comments: 0 Joined: 10/04/05	It is definitely mounted using blind holes. I think you meant to say it does high 30's and the prop pitch is 17. I would raise it 2 holes at first and try the prop you have. It will probably need the 19p for top speed with light loads. Edited by dgoodhue on 03/19/12 - 2:49 PM Dave
Tom W Clark	#9  Posted on 03/19/12 - 7:49 PM
Member Personal Page Posts: 4280 Comments: 7 Joined: 09/30/05	Yes, the lower holes in the transom ("blind holes") need to be filled and new ones drilled 6-1/2 inches below the top holes and 9-7/8 inches apart, o.c. This will allow the motor to be mounted "two holes up" or "three holes up" where it ought to be. See this article for more specific dimensional information: http://www.whalercentral.com/articles...icle_id=82
FlyAU98	#10  Posted on 03/19/12 - 8:10 PM
Member Personal Page Posts: 147 Comments: 1 Joined: 05/22/11	Well thats not what I wanted to hear. I guess it will stay low for a while. I don't have anyplace to get the engine off and fill the holes and let it sit for the repair to dry.... Thanks for all the replies though! Edited by FlyAU98 on 03/19/12 - 8:11 PM