Need Purchasing Advice - 1998 (1997.5) GSX Limited

[Mett248]

Hey everyone, I’m here to ask for opinions as I’m in a bit of a corner on if I should do this.

A family friend is selling a 1998 (1997.5) GSX Limited with 110 hours. I’ve gotten them down to $1200 USD from 3500 (Crazy I know- “shrewd negotiators”, they’re also in a moving situation) with trailer (does need new tires), life jackets, original shop tools, fire extinguisher, 1 key. The condition is pretty good, been garaged it’s whole life so the plastics are surprisingly great, but it’ll need a buff and polish for sure, maybe new traction pads, new handle grips because rubber gets gross, and a seat clean. They’ve been the second owners passed down from their parents.

Obviously it’ll need a bit of work for 21 years old- gas sender gauge needs replacing, the speedo does as well. It’ll probably need a carb tune and clean but starts on the second crank. Compression is good and equal in both cyls, prop is good, new wear ring and carbon seals. Does have the gray tempo lines so I’ll have to swap those. Has the updated air box with rubber flaps. Everything else works- VTS, beeper, computer functions. Will need a bilge clean too since it’s a smelly 2 stroke.

Now I’ve heard the 1997.5’s are notoriously unreliable and aren’t swapable easily for the 98 upgraded one. I’m really unsure if I should just walk away and put my money towards a spark, but with everything as is this could be a “cheap” summer toy and sell it next year, or run it till it dies. Then I could either just move on and use the trailer or try my hand at a rebuild.

Thoughts?

 

[mikidymac]

The head has been off for same reason and the pipe bolt is missing.
@Matt Braley can give you a good history lesson on the Gray Ghost.

 

[glsmohio]

This ski would out preform a spark in every area. I would not hesitate one bit to buy this that's a good price by any means for that ski!!

 

[Mett248]

The head has been off for same reason and the pipe bolt is missing.
@Matt Braley can give you a good history lesson on the Gray Ghost.

I’ve checked out some of his posts and the explanation he gives. Everyone does seem to agree the white 951 just isn’t reliable, or easy to work on. I actually missed that bolt missing I’m glad you pointed that out. I did notice the head must have been taken off. I’m definitely hesitant now that I’ve noticed that. Some of their info on this ski just doesn’t match up with everything I’ve read about the “gray ghost.”

 

[Matt Braley]

I would buy it. The GSX 951 is a pretty perfect model in my opinion. Great performance but not too tipsy and lots of range with the 15 gallon tank. One would have to spend the out the door price of a Spark all over again on a Spark to get it to run with this GSX and then you still would have a plastic boat.

The 97.5 can be as reliable as anything after you address a few issues. You can tell that someone circled back to this particular ski at one point with that flame arrester setup. It may have 98 and newer style carbs also, I can't see what side the throttle cable is coming in on. The original carbs were oriented backwards and had hoses coming off the diaphragm covers leading to an electric solenoid. This with tighter piston to cylinder tolerances helped the 951 register with the EPA.

 

[Mett248]

I would buy it. The GSX 951 is a pretty perfect model in my opinion. Great performance but not too tipsy and lots of range with the 15 gallon tank. One would have to spend the out the door price of a Spark all over again on a Spark to get it to run with this GSX and then you still would have a plastic boat.

The 97.5 can be as reliable as anything after you address a few issues. You can tell that someone circled back to this particular ski at one point with that flame arrester setup. It may have 98 and newer style carbs also, I can't see what side the throttle cable is coming in on. The original carbs were oriented backwards and had hoses coming off the diaphragm covers leading to an electric solenoid. This with tighter piston to cylinder tolerances helped the 951 register with the EPA.

Looks like the throttle cable is coming in from the back of the ski. I checked for the hoses you talked about leading to an electric solenoid, and they were indeed there - I’m going to take a guess that they are original carbs just with an updated air box.

 

[Matt Braley]

Yes it has the original carbs then. Those are also jetted differently then the later ones. Rather then rebuilding those just get a clean set of later ones(can be found for around 100 shipped). Your throttle cable will still work.

 

[Odz]

My fathers 3rd ski was a brand new 1997,5 grey ghost back in 1998. And then it passed to me. All i can say is that pipe bolt was an issue it was always getting off on my fathers white pipe. I would buy this ski for the below reasons.
White pipe - manifold (65mm i/o 63mm on the 99+ models) gain more rpms
Single coil mpem (no TPS sensor, no issues will occur in the future)
Yeah i agree white engines had issues out from the factory.
Tolerance issues.
But white cylinders are taller by 1.3mm
Ports are 1,8mm taller as well, and boost ports are wider than 99 models
Only thing i would change is the carbs and the pump.
Pump is a small hub i would just grab a 155mm plastic pump and drop a solas condord 15/20 in it.



Regards
Tassos

 

[Matt Braley]

The 97.5 is odd because it is single coil but does have TPS.

 

[Odz]

No tps is not at the cable. It’s controlled by the mpem

 

[Mett248]

Yes it has the original carbs then. Those are also jetted differently then the later ones. Rather then rebuilding those just get a clean set of later ones(can be found for around 100 shipped). Your throttle cable will still work.

Alright, Matt, the ski is mine! I’ve done some work already to get it back into perfect condition, and am now at the stage where those carbs and fuel lines need to be redone. So you’d recommend just swapping out to a newer set of carbs vs a rebuild? Any idea where I can find some good information/tutorial on what parts I need to be looking for, and the process to adapt them? I’m having some issue finding any set for less than ~250-300

 

[Mett248]

@Matt Braley this is what I’m referring to... Sea doo carburetors 947 cc GTX XP RX GSX low hours freshwater 98-02 | eBay

 

[Matt Braley]

I like these better. I see others cheaper but they do not look as clean. There are a lot of sets listed but not many selling. I'd send him a offer of 125 shipped. Seadoo 951RX Dual Twin Carb Carbs Carburetors 99 | eBay

Remember that any set is going to need attention to be trusted but it's good to start with a nice clean freshwater set. You will have extra length in your cables so make a space for those that does not include any sharp turns and allow for your storage bucket to not kink them when you slide it in and out. Your hoses will be a little different length.

Also remember that some guys prefer not to alter things. Some members have reported over 300 hrs on all stock versions by using the right oil and warming the machine up well before getting in the throttle. I have tons of parts here so I can bail myself out if it now takes another throttle cable or something. I don't want to lead you in the wrong direction. You could rebuild your carbs, use the 99-02 jetting and needle/seats, and just leave off the rear diaphragm hoses off.

 

[Mett248]

I like these better. I see others cheaper but they do not look as clean. There are a lot of sets listed but not many selling. I'd send him a offer of 125 shipped. Seadoo 951RX Dual Twin Carb Carbs Carburetors 99 | eBay

Remember that any set is going to need attention to be trusted but it's good to start with a nice clean freshwater set. You will have extra length in your cables so make a space for those that does not include any sharp turns and allow for your storage bucket to not kink them when you slide it in and out. Your hoses will be a little different length.

Also remember that some guys prefer not to alter things. Some members have reported over 300 hrs on all stock versions by using the right oil and warming the machine up well before getting in the throttle. I have tons of parts here so I can bail myself out if it now takes another throttle cable or something. I don't want to lead you in the wrong direction. You could rebuild your carbs, use the 99-02 jetting and needle/seats, and just leave off the rear diaphragm hoses off.

I’m thinking I might just rebuild the carbs that are already here and change the jetting if you really recommend it. The set I have right now looks better than any I’ve been able to find online, and at the end of the day I got this thing for cheap enough that I might as well just run the basic preventative maintenance steps and not just throw money at it.

Why exactly do you recommend leaving the diaphragm hoses off if I change the 99-02 jetting and needle/seats? Would you still recommend this if I left the original jetting specs (See below)?

There’s a couple ways I can go from what I see here. Please do let me know what you think...

1. Rebuild carbs to the 1997.5 spec and just clean/replace filters, rubbers, consumables. Keep original spring as indicated by guides here for pop off.

2. Rebuild carbs to the 99-02 jetting, needles, and seats. Replace filters, rubbers, consumables. (Do I keep the original spring or swap to the replacement for pop off?)

The first seems the most simple without having to play around with adjusting low/high/idle and it’s clearly worked as is until now. But this method was changed to the 99-02 right after for reliability so...

Second seems just as simple and would need some adjusting - (but a lot more reliable?), which might be the way to go. Are there any major things to consider when doing this?

 

[Matt Braley]

There is good reason behind the 97.5 jetting being lean and then never being used again. Once they got it registered with the EPA they could concentrate on what is best for performance and the engine.

Those original 97.5 needle and seats are like 1.8's I think. Weird stuff that was quickly upgraded. Since your in the market for genuine Mikuni parts I'd recommend going with the 99-02 specs. If your accel pump does not come back alive I don't think you should spend the money on one just go up 10 on the low speed jets.

I run no accel pump with 95 lows and 167.5 highs pop off around 20 and free flow filters(with pre=filters). With the normal black pipe the highs would be 165's. This is good advice from old tuners that I have used time and time again. BUT once you start modding things you never stop... one thing leads to another and one thing affects two others and.... just go with the 99-02 specs hehe.

The Grey Ghost has little protection from water ingestion. At least get the black rubber piece that goes around the pipe to exhaust manifold area. Those are cheap and easy to install. It's a little bit of insurance against that area spraying water that is going up the carbs.

 

[Mett248]

I have that rubber part already installed. Ordered the genuine mikuni rebuilds from the local BRP store with help from the “how to” thread. Looks like I’d have to get the needle and seats separately if I were to change specs, so we’ll see what the deal is once I get the kits here.

So I found something else today that actually worries me more than the carbs... this last owner must have been a nut with a bad mechanic, because the bolt for the case oil was totally missing and the oil is badly water fouled. I got a replacement bolt and have been trying to flush the old oil with new, crank it, pull it out, repeat. But I don’t think I’m doing this efficiently because the stuff coming out is nastyyy. It also doesn’t want to take a full 40ml like another guide here says. Any thoughts on flushing this stuff out? I need something that can emulsify the water and oil so I can suck it out. I thought seafoam but since it’s for the crank/counterbalance I don’t know if that’s the best idea.

 

[Matt Braley]

That sucks but it's good that you caught that. As long as you get some oil in there I think it will be fine. Maybe try thinning the mess with WD40. It would help displace the water and make it easier to draw out. Any left behind would help lube and prevent rust.

 

[Mett248]

That sucks but it's good that you caught that. As long as you get some oil in there I think it will be fine. Maybe try thinning the mess with WD40. It would help displace the water and make it easier to draw out. Any left behind would help lube and prevent rust.

I’ll give it a shot. Juggling a couple ideas right now- WD40, sea foam and change, all the above + heet in gas, yada yada.

However back to the carb questions! (Thank you very much for the help by the way, I really appreciate it)
Looks like the kit (Mikuni 12-1459) doesn’t come with needles or jets (or case gaskets it seems). I’ll have to get those separately. Using the chart at seadoo source, I would be using the later specifications. They seem pretty drastically different - but I’ll take your word!

Still a bit confused by the accel pump (do I need to be doing anything to rebuild or clean it/ does it have to be tuned? It’s not in the carb rebuild sticky thread) And diaphragm tubes (do I need to replace tubes and keep them as is, or disconnect them? What’s the benefit? Were they removed on the later spec)

 

[mikidymac]

Drain the fuel completely and put in fresh, with no additives other than Stabil for storage.
For the balancer cavity don't use seafoam or any solvents or Heet. Just use WD-40 then the correct oil.

 

[Mett248]

Drain the fuel completely and put in fresh, with no additives other than Stabil for storage.
For the balancer cavity don't use seafoam or any solvents or Heet. Just use WD-40 then the correct oil.

Pumped out and changed both the fuel and 2cycle oils (Klotz Skicraft) and put in fresh 89 + Stabil Marine in gas. Also changed the fuel filter. Tempo lines, the carbs, oil filter, and rave clean is up next.

For the balancer shaft - just squirt in WD-40 with some fresh oil, turn it over, pull the sludge mix out, and repeat?

 

[mikidymac]

Well, unfortunately you need to drain, flush and refill the oil with a new filter because you used the wrong oil.....Klotz is TCW-3 rated not API-TC. I love Klotz and run it in my Superjet but it is not the correct oil for a Seadoo. You have to use API-TC full synthetic oil. The only ones that meet the spec are the Seadoo XPS E-TEC 2-T, Mystik JT-4 and Amsoil Interceptor.

Yes on the balancer shaft flush.

 

[Mett248]

Well, unfortunately you need to drain, flush and refill the oil with a new filter because you used the wrong oil.....Klotz is TCW-3 rated not API-TC. I love Klotz and run it in my Superjet but it is not the correct oil for a Seadoo. You have to use API-TC full synthetic oil. The only ones that meet the spec are the Seadoo XPS E-TEC 2-T, Mystik JT-4 and Amsoil Interceptor.

Yes on the balancer shaft flush.

Oh great hahaha. I knew the TCW-3 but their specifications say for RAVE and their technical support indicated it meets the API-TC spec. No big deal since I have to pull the tank for the filter anyways. The bleeding is going to be a pain though. Do you recommend switching to premix and blocking off the pump, or keep the pump since it direct injects oil?

I’ll flush the balancer shaft as much as I can, run it for awhile, then flush again.

 

[mikidymac]

There is no dual spec oil despite what any marketing info indicates and the API-TC is a much higher spec oil that the seadoo's need.

Bleeding is very easy and no, you should not go premix on these as the Seadoo system is very, very reliable.

Clean the tank out, drain the lines and replace the oil filter. You should also replace the little 3/32" oil lines from the pump to the intake.
Bleeding...
1. Fill the tank with the new, correct API-TC oil.
2. Let gravity fill the lines and filter for about 10-15 minutes.
3. Remove the bleed screw and let all the air out and let the new fresh oil flow a little to be sure the air is out.
4. Replace the bleed screw, DO NOT OVERTIGHTEN.
5. Verify the oil pump arm alignment marks are lined up or even a little over the line for your ski.
6. Start the ski and with it idling hold the oil pump arm wide open. You will see the oil pulsing into and through the new 3/32" oil lines. It should move 1/8"-1/4" per pulse. Once it is to the intake manifold you can shut off the ski.
7. Verify the pump alignment is still correct and the cable did not pop off the arm when you manually moved it.
8. Bleeding is done.

Don't worry, there is plenty of residual oil in the crankcase that it does not matter it is idling without oil while you are priming the small lines.

 

[Matt Braley]

When you take the accel pump off you can put a short hose on the end that draws fuel from the body of the carb and dip it into a spray paint can lid filled with fuel. You can squeeze the spring loaded lever with your fingers and after the 3rd or 4th time it should start squirting fuel out of the other end.

If it pumps fuel like this each time you press that lever in then the pump is good but your not done. The small lines that feed the brass fittings seem to always get brittle and crack so I would definitely replace those. The brass tips themselves love to clog so you have to get them flowing correctly.

If all that is in order then it will run very good with the stock low speed jets. If the pump does not work then I'd leave it inop and run 85 lows with a stock airbox. I say this because the pumps are expensive and a common failure point. Some folks say a 951 has a lean spot at 3/4 throttle, some think that's not really a thing. just to be on the safe side I feel like the larger low speed jets help there too.