motor swap 55hp rude inplace of 90hp rude

[86bonito]

I bought a new to me boat 1987 18ft starcraft (alum) cc. Nice boat minimal dings orig paint with some scratches solid floors all around real nice fishing boat moving up from a 16.5 ft bointo cc this boat looked huge 18ft 4 in plenty of room for my 2 boys and fishing buddy. Boat motor and trailer $600.
Oh ya orig 87 90hp rude. Owner said ran then stopped. I risked it, my bonito was the same but 500$ 88spl got it to run like a champ. Till I blew it getting stuck in the mud. but sold for 600$ broke. tested compression all good 118-120 till the last cylender 0 comp. Pulled head #3 smashed and gouged chamber. My buddy has a 87 55hp rude side steer how hard would it be to swap the motors? I never had the starcraft on water and want to see if its worth having the motor rebuilt. The star only ways 800lbs so the 55 should push it ok.
Any help please thanks

 

[tashasdaddy]

Re: motor swap 55hp rude inplace of 90hp rude

the main problem is if the mounting hole line up. don't remember when they went to standard spacing. everything else should be plug and play.

 

[flabum]

Re: motor swap 55hp rude inplace of 90hp rude

That boat will be very doggy with a 55 on it. We used to sell those where I worked back in the mid '80's. If your'e good with mechanics, you can rebuild that 90 yourself for about $600 or pay about $1300 for someone to do it. I'd put all new pistons (Wiseco) in it and all new bearings with a gasket kit. I know someone in Stuart, Fla that will bore it for a reasonable price. He can even supply the pistons or even do the whole rebuild.

 

[DJ]

Re: motor swap 55hp rude inplace of 90hp rude

That boat will be very doggy with a 55 on it. We used to sell those where I worked back in the mid '80's. If your'e good with mechanics, you can rebuild that 90 yourself for about $600 or pay about $1300 for someone to do it. I'd put all new pistons (Wiseco) in it and all new bearings with a gasket kit. I know someone in Stuart, Fla that will bore it for a reasonable price. He can even supply the pistons or even do the whole rebuild.

Agreed. The Starcraft may be only 800# but it has a lot more "wetted" surface area. Besides, with all that extra room you will be tempted and you will to add more "stuff". The 55 would be marginal performer. The 88 or 90 is a perfect match.

 

[86bonito]

Re: motor swap 55hp rude inplace of 90hp rude

Thanks your right the 55 would be a dog. I have to see how much christmas money I get this year. I wonder if anyone would take trade in on that 55 for the rebuild of the 90?

 

[Kymasabe]

Re: motor swap 55hp rude inplace of 90hp rude

Interesting. I had an early 70's Glastron 17 foot dual console fiberglass boat that had a 55HP Evinrude and that boat used to fly with that 55. I would have thought that a lighter aluminum boatwould have been fine.

 

[86bonito]

Re: motor swap 55hp rude inplace of 90hp rude

I just took a look at the red harness in the motor compartment the 90hrs hase one more pin on the motor side of the connector than the 55. will this be a problem?
also prior owner tried to replace ignition and must have crossed wires wont no power at switch and tilt and trim wont work.
I may just pull all the wires out and refeed them.
Oh ya I may trie to rebuild later but wife was pissed the boat didnt run and says icant put any money into it. Just want to prove her wrong. then taker her out and show her it needs a bigger motor.

 

[Outboardman300]

Re: motor swap 55hp rude inplace of 90hp rude

I have an 1978 17 foot starcraft tri hull that weighs at least 1000 lbs and is 7 feet wide and that thing will go 35 with me and another 200 lb person and it and has good hole shot with an '82 55hp.