650/X-2 Engine Is Toast. Worth Fixing?

[somegt40guy]

Hello everyone,

I have been riding an '89 Kawasaki 650sx with a '91 engine in it.

While stopped, I felt the ski sinking. When trying to start the engine, it took in water and wouldn't turn over. After towing it in and getting the water out it ran like a champ. A couple trips to the lake later, however, it lost power and stopped running. I have experience rebuilding small engines (lawnmowers, etc) and figured I could fix this as well. I would really like to have it up and running in 4 weeks (large family vacation planned).

The cylinder head is toast. The front one is black, and both have chunks missing. I suppose I'll need to replace this.
The cylinder itself is a little scratched. A slight honing should take care of it. I might end up needing slightly oversided rings.
The pistons are quite chopped up on top. They'll need to be replaced as well.

The crankcase looks like it took on a little water. It seems to spin freely, but if I'm rebuilding the rest, should I go ahead and change the crank bearings while I'm at it?

I have looked on eBay and Google for parts, and I'm unsure if the sellers are reputable. Is there a reputable place to buy top end rebuild kits from? How about any other parts I may need? From what I've seen so far, I might be better off spending a couple extra hundred dollars for a professionally rebuilt engine (so I know nothing else is wrong). This option may also be quicker, making it easier to have running within 4 weeks.

I'd gladly appreciate your input and help, having more experience in working on these jetskiis than I do.

 

[burton148]

Just buy a cheap used shortblock. Youll end up having too much into rebuilding your motor for the couple hundred you can buy a decent used one.

 

[Vumad]

I'm not a huge fan of buying used motors if I don't have to. You can buy a used motor that is on it's last leg for $300, or rebuild your motor for $600 and know that everything inside of it is like brand new.

It's worth it to rebuild it except under 2 conditions... 1) You can get a replacement motor so damn cheap you can't pass it up, like a whole running ski for $300, then sell the ski again for $300 so you pay nothing for the motor, but deals like that are few and far b/t. 2) You are upgrading. It's worth it to buy a used 750 motor to replace your 650 motor.

If this were a superjet and you can buy a motor that is 3 years old with low hours, then I might agree to just buy a running motor. However, kawi stopped making the 650 in like 1995, so anything you buy will be 20 years old. It may be cheaper to buy a used running motor, but replacing broken parts with worn out parts is a poor long-term investment.

Lastly, I would part that ski out and buy a superjet or SXR that is newer and in better condition with better handling and etc. I wouldn't fix it because I wouldn't put any money into a 650sx.

 

[Mdavies_02]

Lastly, I would part that ski out and buy a superjet or SXR that is newer and in better condition with better handling and etc. I wouldn't fix it because I wouldn't put any money into a 650sx.

I agree with everything you said, including not putting money into a 650sx. I had one and literally gave mine away once it gave me enough problems.

 

[dbattersby20]

I would rebuild. I went through a similar problem and my 650 was toast I graded to a 750 with pipe and a couple other things I wish I had rebuilt a 650 and just made it as nice as possible.

 

[89sx]

I just went thought the same thing. Bottom ends are a little hard to find but if you can find a good bottom end you can buy all the top end stuff. Thats what I did and so far so good. Knock on wood.

 

[01GS]

A rebuilt crank is the most expensive part so if your bearings are ok I would rebuild it. As stated above buying a used can be a can of worms even if it's running. It could have bad bearings even though it runs. You can't really rebuild a crank unless you have a press and some fixtures/tools to hold it and even then if you don't know what you are doing it won't end up right. You are better off trying to find a used crank in good shape if you can to save some money. If you want a motor that will last for years to come get a rebuilt crank. Also heads are really cheap so I wouldn't worry about finding one of those. If anything this is a good chance to buy a milled or aftermarket head to get a little more power.

 

[Jpass]

just found out I need a new top end on my '88. First one in 25 years. 165 front 60 rear.