Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: 1998 70hp Johnson on Montauk prop

Posted by scottfarm on 03/04/12 - 1:29 PM
#1

I have a 1987 Montauk with a 1998 70hp Johnson. My engine is raised on the transom as high as I can get it without cavitating. I need a new prop. From all the reading I've done the consensus is I need a Stilleto 13.25 X 15. Could I use a 17 pitch since I have my motor raised so high. I have a 28 gallon tank and my wife as a passenger and sometimes a bait tank. Does Tom Clark still sell these props and if so for what price? Thanks a million Dennis

Edited by scottfarm on 03/04/12 - 1:30 PM

Posted by Joe Kriz on 03/04/12 - 1:33 PM
#2

How high is "High" ????

Please tell us which hole the bolts go through on the engine mounting bracket according to this diagram.
http://www.whalercentral.com/articles...cle_id=106

Posted by scottfarm on 03/04/12 - 1:39 PM
#3

Two Holes Up (bolt in third hole)

Posted by scottfarm on 03/05/12 - 6:15 AM
#4

What about a Powertech 13 3/4 X 15?

Posted by tedious on 03/05/12 - 6:45 AM
#5

scottfarm wrote:
I have a 1987 Montauk with a 1998 70hp Johnson. My engine is raised on the transom as high as I can get it without cavitating. I need a new prop. From all the reading I've done the consensus is I need a Stilleto 13.25 X 15. Could I use a 17 pitch since I have my motor raised so high. I have a 28 gallon tank and my wife as a passenger and sometimes a bait tank. Does Tom Clark still sell these props and if so for what price? Thanks a million Dennis


No, you shouldn't go with a 17-pitch unless you always run very light and are primarily interested in absolute top speed on flat water - you'd be giving up quickness to plane and you might even have overheating problems when running loaded. You really want the WOT to be right up around 6K for proper cooling. The Stilletto 13.25x17 / 70 combination is great on a 15, but for a Montauk you want the 15 pitch.

I don't know if Tom is still in the prop business, but Dan's Discount Props is also good.

Tim

Posted by scottfarm on 03/05/12 - 10:21 AM
#6

Thanks man, That's the cheapest site I have found for props.

Posted by Tom W Clark on 03/05/12 - 5:32 PM
#7

Dennis - I agree, the 13-1/4" x 15" Stiletto Advantage will be the best fit for your 1998 Johnson 70 with its 6000 RPM reline and 2.42:1 gear ratio. $250 delivered to your door with hub kit included.

Posted by dgoodhue on 03/05/12 - 5:33 PM
#8

With a Stilletto you maybe able to raise the engine another. I agree that 13 1/4 x 15p is the correct prop for your application.

BTW I would contact directly about buying a stiletto prop.