Seadoo 657x

[Paul gts]

I've got a 95 657x engine that I had running from a 95 parts ski that got rock damage to the pump and hull. When I was stripping down the engine to install in another 95 gtx I noticed black oil in the exhaust manifold and took the cover plate and rotor off. I tipped the engine on it's side and recovered 4 ounces total out of both ports( crank case) it has 150 psi on both cylinders and the rotary valve has a slight rust halo on the backside of the rotor , telling me it sat for a while. It looks to me it sat for a while and I think the oil in the crankcase on both sides is telling me the center seals are back and weeping oil. So, my question is if I try to run it will the seals tighten up or should I not bother and rebuild and is 4 ounces of oil acceptable for a motor that sat a while ?

 

[mikidymac]

Not uncommon for them to leak some oil when sitting a long time.
4 oz is nothing to worry about.

 

[Paul gts]

That was the info that I was hoping to here. Just wanted to here some opinions before I wasted the money on new gaskets and the time wasted of installing everything. Thanks mikidymac

 

[mikidymac]

When the inner crank seals do go it’s not just gaskets, you will need a remanufactured crank as the inner seals can’t be done at home.

 

[Paul gts]

Yeah , I saw SBT had a reman for $285

 

[Paul gts]

Actually just got done reading everything you were saying in another older thread about API-TC vs TCW3

 

[etemplet]

Oil isn't your problem. Put the engine together and pressure test the reservoir. Before I spend a ton of money replacing a good crank I'll happily put a valve in the feed line. You many not even have a problem at all. Good Luck !

 

[Paul gts]

Oil isn't your problem. Put the engine together and pressure test the reservoir. Before I spend a ton of money replacing a good crank I'll happily put a valve in the feed line. You many not even have a problem at all. Good Luck !

So your saying the check value vent in the top of the oil tank can cause oil to build up in the crank case on both sides of the engine if it's not venting?

 

[mikidymac]

So your saying the check value vent in the top of the oil tank can cause oil to build up in the crank case on both sides of the engine if it's not venting?

No. Some people that have leaking crank seals install a ball valve in the 12mm feed line going under the intake manifold to shut off the oil tank when not in use.

This can buy you some time but eventually the seals will get bad enough it floods with oil all the time.

 

[Paul gts]

Oh ok, I get it. I actually have 2 657x engines from a couple donor ski's and I just tore into the 2nd one . It has a little bit more oil in it but the cylinders are in awsome shape. Can still see the cross hatch and the pistons look great too, atleast through the exhaust ports. Think I'm gonna get a gasket kit and run her. Hey mikidymac, what oil would you recommend that is API-TC that will still smoke so I can just tell by running in the water and notice when I start seeing more smoke that it's time for a rebuilt crank ? The plugs might start to foul more too I guess. And I have to say, I'm 55 and my wife and 2 more couples got into these older smooth bottom gts and gtx pre 96 and we love em. I really appreciate all the info. Thanks

 

[etemplet]

I think those old two-strokes are the best deals on the market. I run Lucas Synthetic Blend in all my skis. Synthetic is about $5 more a gallon and I'd run that in a 951 DI. Have fun !!

 

[Paul gts]

Oh yeah, that says API-TC and I think alot or maybe most say tcw3 aswell. We love the old 3 seaters. I restored a pair of 94 gts's for me n the Mrs. And put a new (rebuilt) 587 in my friends wife's 93 gtx last year.

 

[etemplet]

Yep those are fun reliable skis for sure !! Good Luck !!

 

[Paul gts]

Yep those are fun reliable skis for sure !! Good Luck !!

Thanks

 

[Venturian1]

100% synthetic is better than any blend. Costs more tho!