Just purchase 98 sportster 1800, needs a little work, have a few questions

[jeffbeckib]

OK, so I buy this 98 sportster 1800, This is my first boat and I know nothing about motors and such. I know the port motor had some issue, and the owner told me he felt it was a rotary valve.

One motor runs fine, the other stalls when Idle, to start it up again I have to put it in fwd and give a little throttle, then she starts up, but still runs rough. Took it to Seadoo, they did a compression test and found the port side was reading 150/60, told me one cyl is bad and engine needs to be replaced. Also told me I'm missing the 2 flywheel covers and suggested I don't even put the boat in the water until I get those installed. So here's my concerns.
#1, Do I really need to replace the entire engine for 1 bad cyl?
#2, If I do, is there an aftermarket motor I can put in instead of Seadoo's $1,200 refurb rotax?
#3, What are the flywheel covers function? because if it's only function is to keep water off the fly wheel, that seems like it would be an impossible task since the entire bottom of the flywheel would be exposed.

Hope I don't sound like an idiot, even though I am one for having purchased a boat like this knowing nothing about them.
I got it for $2,500 and I'm hoping I don't have to put stupid money into getting it to run.

 

[howie099]

An engine starts around $750. Topend around $250. If the dealer can ready the MPEM and you have under 200 hours a topend will hold you off a few more years. Both covers are like $100 used. The old owner should of gave them to you. You need the covers to protect the stator, flywheel, and starter. They will all start to rust with out them and the starter will lockup.

If the rest of the boat is in working order and looks good you have a pretty good deal. I would get the MPEM read so you know about how much longer the other engine would have left on her.

I don't know why you would take the stator/flywheel covers off to compression check or to work on the rotary valve. Only need in there to access the stator.

 

[jeffbeckib]

An engine starts around $750. Topend around $250. If the dealer can ready the MPEM and you have under 200 hours a topend will hold you off a few more years. Both covers are like $100 used. The old owner should of gave them to you. You need the covers to protect the stator, flywheel, and starter. They will all start to rust with out them and the starter will lockup.

If the rest of the boat is in working order and looks good you have a pretty good deal. I would get the MPEM read so you know about how much longer the other engine would have left on her.

I don't know why you would take the stator/flywheel covers off to compression check or to work on the rotary valve. Only need in there to access the stator.

According to Seadoo's receipt, the Key Board has 129.7 hrs, and the boat has 129 miles
Forgive my ignorance, but I don't know what the difference is between a topend and an engine.
They quoted $1,297 for a seadoo refurbished short block 717 plus other misc rings and gaskets + another 7-9 hrs at $125/hr

 

[howie099]

You can get am engine from like SES for like $750 w/1 year warranty on it. You have t opay to your engine to them and wait for them to rebuild it. You can get one from SBT for the same price but you get it right now and don't have to wait for yours to be rebuilt. I think SES uses better parts but you won't get to use your boat for a month or 2 while they rebuild it.

The topend is the Pistons and cylinders. Bottem End is the crank. You can do this yourself and save like a $1000. It is not as hard as you think to swap them. I know really nothing about them you might be heading to a dealer or indendent shop.

I would guess with that low of hours the oil system has some issues or the fuel system is the problem. I bet the carb filters and mucked up..

 

[dbracela]

The problem with just doing the top end is that you have no idea what caused that engine to fail. If something in the bottom end is messed up, you'll be wasting time and money on the top end. If you get a reman form sbt or ses you can install it yourself if you have the manual. You'll save a bunch learning to the stuff yourself.

 

[jeffbeckib]

The problem with just doing the top end is that you have no idea what caused that engine to fail. If something in the bottom end is messed up, you'll be wasting time and money on the top end. If you get a reman form sbt or ses you can install it yourself if you have the manual. You'll save a bunch learning to the stuff yourself.

Does anybody have a link for documentation on installing a motor? and/or replacing the top end?
So I can evaluate weather it's something I can handle.
My concern is the tight space to work with, but it's worth a look.

thanks

 

[dbracela]

The shop manual has a pretty good description. YouTube has some good videos.

Space is tight in there, but it's doable.

Have you spoken with the previous owner as to why the covers were off?

 

[jeffbeckib]

Well got the bad news today that the motor is shot and doesn't pay to do just a top end on it, not sure exactly what's wrong, but this is the 2nd mechanic to tell me it needs a new motor so i'm going to assume it's not worth rebuilding. So, my next question is:

how many hours should it take a qualified mechanic to install a motor?
And where can i get a rebuilt rotax 717/720 with some kind of warranty??
What should I expect to pay for this motor?

 

[howie099]

Many shops will rebuild them. SES, Fullbore, or SBT are just a few. All offer 1 -2 year warranty on them. I would guess most shops could it in 8 hours.