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1997.5 GSX Limited Brand new motor help!

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Bbarnumboy

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Hello and thanks for having me on your forum. I am glad to finally join since your archives of technical data has helped me immensely.

I will try to make this simple, but very clear as to what I am dealing with and how you can possibly help me out.

First off, I am the proud new owner of a 1997.5 GSX Limited with the 951/946 carburetor engine. I picked up the ski for a very good price due to the engine being shot. At first I thought it just needed a top end job, but it ended up being a full engine rebuild. I sent the engine out to Full Bore for their premium rebuild and it came back with everything looking very mechanically sound. I will touch on the things I have done to the engine at the time of rebuild and install and it would be great to get some feedback on any ideas to help me out.

I just got the engine started yesterday for her maiden voyage. She ran just fine, aside from needing to adjust the idle more. I decided to get her on the water and see if I can start the break in process and fix the idle. Once on the water, she did not want to start. Since that time I can only seem to get it to fire up when I turn the gas shut off valve to closed. It will run just fine until the line runs out of gas, maybe 20 seconds. During this time of running, if I turn the gas to on or reserve it will bog real bad and then die. I believe my fuel mixture is way off. So that is my issue, now to educate you on what I have done to get me here.

Full engine rebuild, I also had the Mikuni carbs sent out for a full authentic rebuild, using the proper Mikuni carb rebuild kit. The guys also set everything back per the manual from what I know in regards to the needles etc. I put in authentic synthetic seadoo oil in the injection tank, I primed the oil lines with a drill motor after bleeding the air out as well. I did notice I had to route the oil pump arm a full revolution in order to get the spring tension, and then I lined up the marks to set it in place. (was that wrong)? otherwise the cable will not return because there is not spring tension? I am not certain if this is causing way too much oil or if it is just fine now.

I have read that the 1997.5 has the left side solenoid for the carburetor diaphragms in order to lean out the mixture at a specific rpm/load. I'll read this can be deleted because this is a problem with 1997.5 having engine issues? I also read that in 1998 they got rid of that. The previous owner had it unhooked. what I did was removed the line from the solenoid on the left side of ski that runs to a t fitting, splitting off to supply a vacuum line to the side of each carburetor and capped the ports on the carbs. (Is this completely wrong to do and do I absolutely need those lines going to the carbs back on)?

I also could not locate the idle screw for the life of me. looking down on the carbs, standing on the left side of the ski I noticed a t handle valve underneath the accelerator p housing on the left side/ Magazine carb? I started adjusting it (very hard to get to) with no luck. I hope it was not a fuel mixture screw :-( did I just Fubbar my settings now? I have looked at the manual and pictures and just cannot find the idle set screw.

I also have old gas, I plan to remove that. it is about 7 months old in the tank and has a mixture of oil in it as well for the break in process which seems to be standard.

My last concern was with a few of the crank case lines on the PTO end of the engine on the left side under the carbs. I have 2 bronze fittings coming out, one points kind of Forward and the other points Aft. the manual also says I should have a 3rd port just under these bronze nipples. My block had a bolt in place of this port. The manual says that port should have a check valve and run a line to the right side solenoid that powers the Rave valves. I ran the check valve line from the rave valve solenoid to one of the bronze nipples instead. After much research I found a drawing that showed a vacuum/pressure line on the fuel entry and exit side of the Carburetor that says the line goes from the Carb to engine. It doesn't show the other end and no other drawing I found showed what plugs into these bronze nipples. So I plugged a line from the last carb port remaining on the fuel line side, down to the other bronze nipple on the crankcase (was that wrong)?

I also have no lines to the air box, as the previous owner put some kind of one way check valves inside. I also have a clear tube that goes to the hull somewhere up by the gas tank that has no home to connect to. I also have one small black line left that is coming from the battery/ pump/ vts area in the rear of the ski. as far as I can tell from the drawings, my water lines are all correctly in place, the fuel lines connecting the carbs together and the fuel in and out appear to be correct as well.

I am sorry this was lengthy but I wanted to get the whole background story out there. Hopefully someone can help me sort out my questionable vacuum/ pressure line questions and help with dialing the fuel delivery issue in.

Thank you and glad to be in the community.
 
You need to leave the fittings on the back of the carbs open. Those diaphragms need to fluctuate.
 
So is ok not to have it hooked up to the solenoid? just leave the ports open to atmosphere? I'm not a huge carb guy so I don't really know how those effect anything. Thanks for the reply, that may be a good step forward.
 
yes open to the atmosphere. All other carbs are that way, yours was just the model that they had to register the 951 with the EPA with. Plug the vacuum line that feeds that rear solenoid.

The adjustment needle underneath with the roll pin though it was probably the low speed. It needs to be 1 3/4 turns out from closed.
 
From your description it sounds like you might have plugged your pulse line. It connects from the "forward bronze nipple" to the front carb body and actuates the fuel pump.
 
the front bronze nipple is connected to the rave valve solenoid. the rear bronze nipple is connected straight up to the carburetor next to the fuel in and out ports. the tiny little lines with the filter that connects from carb 1 to carb 2 are all done correctly. the only other nipple on the mag side carb is the diaphragm one that I had a cap on.
 
Is the routing for my 2 gold nipples correct?one going to rave solenoid and the other to the PTO carb end?
 
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Matt Braley that was the answer. I pulled the plugs off the carbs and it fired right up. I just put her first 1.2 Hrs on the rebuild.

Things I noticed on the breaking in. It has 1 or 2 groggy dead spots. The main one is around 3300-3800 rpm. A little more throttle and it jumps right to about 4500. I can't get it to cruise between 3800 and 4500. it wants to get stuck around 3800 and be boggy unless I give it more. zwhat jet do I need to adjust for this issue. She cruises smooth at 4500 and if I give it a little more it stays smooth. I'm not going open throttle yet so I can't say how that is working.

Also let's talk oil consumption. I want to make sure my oil is working. I marked a line but it's kind of hard to tell if my angle etc is the same as when I marked it. In 1/4-1/2 tank of gas should I have consumed quite a bit? I am not sure how many tanks a gallon gets you.

Thanks for saving summer!
 
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No problem, glad you got a ride. When you get it into the groggy spot start pulling the choke out. If it smooths out and pulls forward then you have a lean condition. If it falls on it's face then your rich. Determining that will tell you which way to go with the low speed adjusters. If rich then turn them in 1/8 turn increments while testing in between to see if it's clearing up. If it's lean then turn them out an 1/8 turn at a time.

The oil does not disappear from the tank too fast. It takes you a few tanks of fuel to work it down. If nervous(and since you have a fresh engine) you can add a little oil to the fuel tank. Not much like an once per gallon. Your oiler is working though or it would have locked up in a lot less then 1.2 hrs.
 
Quick question, since pictures don't seem to do justice. are the small town handle adjusters on the bottom of the carbs the low speed adjusters? and the bronze flat head screws on the top, the high speed adjusters?
 
Yes, the screws are as you described.

As for the flat spot at 3,800 rpm that is about when the rave valves start to open I think so that is perfectly normal to not be able to hold in that range.
 
So I took the trunk out today and filled the oil all the way up to the top of the tank so I can see the oil consumption better. Iput another 5 gallons of premix in the gas tank as well. I reset the low and high speed adjusters as they were off. The high speeds were set at 1 turn out and the manual says my model should be set at 0 turns out. I decided to go the safe route and set the PTO to almost 1/4 turn out since that's what they did on the 98 version instead of my 1997.5 Do you think that is ok? I just always hear about the 97.5 model having issues. I reset the low speeds and put them at 1 3/4 out. the ski runs much better now. I can hold rpm between the dead zone that I had before. Still a little groggy and gurgly at 3300-3800 if cruising.

Over all I am satisfied. this ski wants to just take off and I am holding out for about another tank of gas. I have about 10 gallons through it now and around 3.5 hrs on the rebuild. After a 2.5 hour session today, I have confirmed that the oil injection is for sure working just fine.

Thanks for the help guys, I really thought setting the carb adjustments and figuring out my issues would be way more of a headache. The only pain in the ass was getting my fingers on the low speed adjusters but I got it. The Only thing left to figure out is why my speedo does not work. It is all connected and the temp gauge works. I must have a bad unit that needs replaced.

Loving summer so far!
 
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Ohh...a Gray Ghost!! I want one some day just cause I like the look of them. After reading the entire thread I would think that if you stopped premixing and just went with oil injection the groggy spot would become even less noticeable.

Good find and good luck.
 
Thanks, I scored the ski for a great price knowing it needed a rebuild. I Hope it clears up and I think you are right. I will be using premix added for probably another 10 gallons and then the fun begins
 
For a new engine break in the premix is only needed for the first one or two tanks, especially now that you know the oil injection is working.
 
Yeah I only have one tank through it so far. One more with premix and I'm calling it good to go. any advice on the speedo not working aside from checking resistance?
 
Both my 1997 GSX and GTX don't work. But every once in a while, they will come alive for like 3-5 seconds, they each behave the same exact way. I have heard that the sending unit often goes bad on those years. (my 1996 XP works just fine and never had issues on my prior 96 GTI and 95 GTX)
 
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