62T worth rebuilding?

[hink320]

I bought a 97 waverunner 760 yesterday for cheap...I knew that it had a piston issue, but it was cheap and I haven't torn apart a Yamaha engine yet so I wanted to experiment on this before I tear down my xs865. Did a compression test before tear down and found 130psi in pto side cylinder, but only 30 psi in the other cylinder.

Looks like the one piston ring let go and caused all the damage.



The cylinder wall has 2 small gouges, and a couple of the ports are dinged up a bit. Think it needs a resleeve or can I just bore it over?

Think it's worth it to rebuild it, or should I just scrap it and part it out. The original plan with this ski was to do just that, but the hull is mint, actually everything about the ski is mint if it weren't for this piston ring.

 

[Vumad]

Is there a chunk missing out of the left bottom of that jug?

 

[JetManiac]

Yes it is worth it. You can bore and put new pistons or just put a clean used top end on it and run it.

 

[hink320]

Is there a chunk missing out of the left bottom of that jug?

No chunk missing, it's just sitting on some foam making it look like it.

 

[XJCrawler]

Rebuilt it

Are you coming to Daytona?

 

[hink320]

Are you coming to Daytona?

I don't think so, I'm going sledding in Revelstoke Jan 24-28.

 

[Vumad]

When I rebuilt my motor, I had a friend who got the parts for me at cost. However, if I had not gotten them at cost... bore $160, pistons $160, wrist pins, etc everything would have been like $400. I think the Jetmaniac BB top end kit is like 650 or 800 with the porting work?

If the crank and cases are good, there's no doubt to rebuild it. I would pay the extra and have someone work it when they rebuild it for that kind of money. Toss a ADA with interchangeable domes on it. Sweet ride.

 

[hink320]

What I was actually wondering was whether or not it was worth it to rebuild it and put it back in the waverunner, or should I just keep it as a good spare motor?

 

[Nemo]

First it starts with one spare, it's all down hill from there. Next comes the spare hull and the spare hull spare engine.
So YES rebuild it and let the parts spree start

 

[badvinny]

For sure rebuild it as long as the bottom end is decent. Pull it apart and check the crank, put it together with new seal and rebore the top end, many years of good use left I bet!

 

[Andrew1289]

+ 1 on new engine seals.

 

[Therizzlejebus]

You should sell it to me cheap and broken so I can rebuild it for my 650 sn