TOPIC: Repowering a 1965 Slickcraft

The Grasshopper, our 1965 Slickcraft SS-180, is having itself an existential crisis and needs help!

The motor, a 1965 Johnson Seahorse 90 hp, which became a 100hp after a fire and carburetor replacement, which gained the lower unit of a completely different motor (note it's black in the photo), has finally decided to give up the ghost completely, so we're looking a repowering.

The trouble is, we can't seem to find any information on the maximum transom weight. All the literature says is that the transom can support up to 100hp, but with today's motors being so much heavier I'm not sure what we can put on it. We'd like to keep as close to 100hp as possible. Does anyone here have experience with these repowering these Slickcrafts?

Chris. that old motor was a beast. Looking up some info the motor was around 230# dry. I used to have one of those and they are huge compared to todays size/hp ratings. Right now I have an 85hp Johnson 4 banger that weighs in at 275# and a 140hp that weighs 325# Looks like your transom is high enough to handle a heavier motor without any problems if it is solid.
How much newer do you want to go? You could run a 1970's Johnson or Evinrude triple and probably get better performance and gas mileage. Shop craigslist in your area. I see in one of the pics you were in Fox Lake. (WI) ?? If so search the Milwaukee to Green Bay listings or you could follow the Rawhide.org website ebay listings and pick up a good parts boat for less than $500. with a good motor and controls. Here's what's available now until Monday night. cut and paste the link and remove to two spaces I put in.
https: //www.ebay.com/ itm/16-Steury-T316BB-70HP-Evinrude-Outboard-w-Trailer-T1283294/372956867719?hash=item56d5f62c87:g:hoMAAOSwM0hdpiP5
Just a suggestion.

63 Sabre wrote: I see in one of the pics you were in Fox Lake. (WI) ??

Nice, I thought someone might pick up on that! We're on the Illinois side.

We've had a lot of experience with grabbing parts from older motors and I love the simplicity and authentic look, but my retired parents who use the Grasshopper most of the time are getting tired of reliability issues and want something newer. The concern has been going from a ~230 pound motor to something much heavier (with the same horsepower). The lightest new 100hp outboards we can find are around 325-350, and so we're concerned about the transom weight. Any ideas there? Sound like you think it can take it.

Thanks!

Hello Chris,

The Slickcraft is a beauty. Dick’s Marine in Fox Lake could make that old Johnson run like new.

We keep our 59 Glasspar on Pistakee Lake near Freddie’s Roadhouse.



Hope to see you out there soon.

Terry

Hey Terry, never lose an opportunity to show off the beautiful Mama Mia. Depressing rain the past few days. Just want to get on the water and "social distance" even if I have to wear my long johns.

Thanks Cal,

Hey smoke em if you got em, Nothing like doing some “ShowBoating”


Mama Mia! at Bar Harbor on Gull Lake MN.


One of Bill's favorites is his 59 Barnes Shark. We have tentative dates of July 18 and 25, 2020 for the Blackhawk Chapter Fox Lake show at Famous Freddie’s.


Haven’t heard from Bill on the Lake Kosh event but looking forward to the Island Bar and Grille too.


My favorite from the Bill’s collection is the 59 Samoan.

Terry

Terrydi wrote: The Slickcraft is a beauty. Dick’s Marine in Fox Lake could make that old Johnson run like new.

Gorgeous! We used to launch from Ben Watts, so we probably crossed paths many times.

As for servicing, we've been going to Haling for many years now, ever since we had a bad experience at another marina. Good to hear good things about Dick's. Still, I think my parents are tired of the perceived risk of running the old motor, having lost a couple of summers now to engine issues.

I know it isn't the same boat, but I went from a Golden Meteor 100HP to a 90HP Etec. I hae a funliner. My boat had an option for rear seating adn since my boat doesn't have that, I assumed that it wouldn't bother it. My beam is also really wide, so the displacement was minimal. My transom was solid also. The recommendation I received when I was repowering was to add the weight over the transom while it is in the water to see how it impacts the distribution.

The ETEC 90 I3 is the lightest and closest in HP you wll find. I researched them all.

damartinca wrote: The ETEC 90 I3 is the lightest and closest in HP you wll find. I researched them all.

Oh my... what crazy timing! I guess there will still be parts available for years, but did you find anything else that's close?

yes, I’m very shocked. the Suzuki is the next lightest at 343lbs. however, I had almost pulled the trigger on a Mercury which was 352 or so. I’m disappointed in BRP more than anything else. They actually have a superb product. It didn’t deserve to die this way, but in the end it is always the bottom line.

Best of luck with your repower.

Shocked indeed - thanks for the info. While I'm pumping you for information, how much less fuel are you using with the E-TEC versus the Johnson?

Related question: did the change in SAE horsepower ratings from gross to net in the '70s change outboard horsepower ratings as much as it did for cars? The difference for car motors was as much as 30%, but presumably they have a lot more parasitic loads than a 2-stroke outboard. Wondering if I can go a bit lighter on the horsepower and expect the same performance.

Also, are there any good online classifieds for new and used outboards? It seems really fragmented, except for eBay.

OK, the hard part is over with the help of @damartinca. A new E-TEC 90 horse is being fitted almost as we speak.

Any advice to be had on props, beyond what's generally out there on the internet regarding testing at cruise and at wide open throttle?

The prop we have now has always worked fine, but obviously the new motor will have a different operating range. We aren't trying to go any faster (or slower, for that matter), just wanting to optimize efficiency.