Siezed 701 - teardown help

Been having fun all summer on my 96 waveblaster. Mods include head, red riva pipe, scoop grate, impeller, jet dynamics ride plate, & others.

It has been converted to premix

Ski had been running great all summer.

A few days ago, I just launched, let the ski warm up (nothing over 1/4 throttle for a minute or so)

My brother and I decided we were going to head down river about 1 mile to catch up with a few friends who were already down that way. So my brother (riding a 1100 sitdown) and I (on the blaster) headed off pretty fast. After about 1/2 mile out, I had the ski pretty well pinned trying to keep up with the 1100, if not completely wide open throttle. Cruising along nicely, then the motor just fell flat on its face. Wasn't a complete lock up, just went from pinned to dead in about 2-3 seconds.

Came to a stop, I hit the starter, I could hear the starter trying to crank it over, but it was pretty locked up. It felt like it would try to crank 1/10th of a revolution, but just couldn't turn over. It had the exact same feeling as being hydro-locked. But there was no water in the hull to hydro-lock the engine.

So my brother towed me back to shore.

Today when I wasn't home, my brother started digging into it. He owns a small engine repair business and is very good at rebuilding engines. He called me early today and said that one of the first things he did was a compression check and the front cylinder was extremely low. I think he said 25 or 75 lbs.

He said that he would gladly tear into it to see what all went wrong. I trust his mechanical ability, I'd just like to ask on here for some advice as to how best to dig into this.

I only natually assume we will be pulling out the entire engine. How best should we pull the engine. Is there anything that should be left attached, anything that should be not completely removed, but maybe just moved back out of the way. This is a 96 dual carb blaster.

It doesn't seem to be much of an issue to pull the engine, I just want to make sure we aren't doing extra unnecessary steps.

Furthermore, what should we be looking into as for the reason why the engine seized. Carb leaning out.

The pisser was running fine, so it wasn't that the engine overheated. The premixed was properly mixed, so it isn't that either.

I remember a while back a friend had to do a rebuild on a seadoo because of crank seals going out which causes a lean condition. Could that be a potential culprit on this 701?

Any advice that I can get will be greatly appreciated.

:sadwavey:
 
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You wont know what killed it until you get some good pics of the carnage. If it is premix, and you were running proper octane, and your pisser was flowing then I would guess something made it lean. Either carb problem, or seals, which jug has the low compression?
 
Speaking of pissers i was looking around my 93 superjet for a pisser and i cant find one anywhere unless its in the back where my jet stream comes out. I know alot of the yammys have the safty stream that shoots up behind you but i dont think mine does. All i can find is where my bilge hose comes out the side. Just wondering.
 
Speaking of pissers i was looking around my 93 superjet for a pisser and i cant find one anywhere unless its in the back where my jet stream comes out. I know alot of the yammys have the safty stream that shoots up behind you but i dont think mine does. All i can find is where my bilge hose comes out the side. Just wondering.

sounds like u got shorted a pisser....
 
Dang that sucks. I guess ill have to make sure i keep it flushed pretty regular after rides then considering how much of that nasty ash we have had dumped in our lake from the steam plant. I had my bass boat pisser stop up a few weeks ago from it.

I also need to look into getting a flush kit adapter for it. It has a hose to coming off the pipe but i dont have the adapter to fit on it and hook my waterhose onto. Does anyone have any idea where i might find one?
 

2006superjet

just one more part....
Location
costa mesa ca
mine did the same cost me 1000$ through jetworks.
they told me it was the yamalube 50-1 mixing
now i run 40-1 synthetic. and no issues they did tell me take it east on the wot runs but i rarely do those.
my pisser is still hot through even running around 20-30mph it stays the same temp but seems hot. oh well maybe it was the 83 deg water
 
I've run extended WOT runs before, running 92 octane with never an issue. If lets say it wasn't a carb issue, could it have been not enough octane & detonation? I think it is a 175psi head.

The only reason I ask, is because I've heard of people running higher psi heads on pump gas but they said that you have to keep WOT runs to no more than 10-15 seconds.

Also, for the person before saying about dual cooling, there is a single pisser (mods were on this ski when purchased). Should I look into dual cooling?

I need this ski to be reliable even at WOT. I only run flatwater, and many times the water is glass smooth making for fun high speed carving or in the recent case, I need to be able to keep up with couches.
 
I've run extended WOT runs before, running 92 octane with never an issue. If lets say it wasn't a carb issue, could it have been not enough octane & detonation? I think it is a 175psi head.

The only reason I ask, is because I've heard of people running higher psi heads on pump gas but they said that you have to keep WOT runs to no more than 10-15 seconds.

Also, for the person before saying about dual cooling, there is a single pisser (mods were on this ski when purchased). Should I look into dual cooling?

I need this ski to be reliable even at WOT. I only run flatwater, and many times the water is glass smooth making for fun high speed carving or in the recent case, I need to be able to keep up with couches.

yes look into dual cooling...blasters run hot and you are screaming that thing it sounds like....and put in a bigger main jet like Supertune said....he is one of the best engine builders known...
 
Just today my brother and I got around to tearing down the engine. It is going to need a carb rebuild kit, engine gasket kit, overboring the cylinders, & piston kit.

So it got me thinking, rather than rebuilding stock 701 parts (engine & carbs) are there any options for going with a bigger engine & carbs, but not breaking the bank.

What about the 760 engine? What about a good set of used performance carbs (from the wanted/for sale section on here), for roughly the same cost as rebuilding the stockers?

Is it feasible to upgrade for roughly the same cost as rebuilding?

Will a 760 bolt right in, reusing the aftermarket 701 head & red riva pipe?

As stated in my initial post the current mods include head, red riva pipe, scoop grate, impeller, jet dynamics ride plate, & others.
 
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