96 GTX SBT Replacement help

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JDawg965

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96 Sea-Doo GTX 787... I bought this over the summer as a project, I bought an engine from SBT great people!!! I finally got around to putting the engine in, and I have one thing I can't figure out so far, there is a vacuum line coming from the rear of the ski that I can't figure out where the hell it goes??? Everything else seems to be hooked up and I can't find a spot for that??? I have a picture I will try to post with it!!! And help would be awesome Bc I wanted to attempt to fire it up tonight
 
If it ends near the battery box it is for a vent for acid batteries. It goes up towards the front of the ski and out a side vent. If you have an AGM battery, you do not need it.
 
Is there one that connects to the top of the exhaust manifold? I have a hole there and was looking online and some show a line running there to a fitting which I don't have??? I was going to tap it and put a new one in unless it's not needed
 
is it the one shown here? This is my 96 GTX.
376.jpg
 
Yes it runs to the tow hook!!!! And yes it's the one shown in the picture however it must have been broken off when I bought it Bc I don't remember it being there before I pulled the old engine... what should I do???? I was gonna drill and tap it... but what can I do??? Thanks!!!!
 
Well my ski is put away at the moment, but if that is the pisser line, then you can just plug it for a test. It will not hurt it running. But you should have one so you can see it is cooling and it may bleed air out. For sure you can start it that way. Is it an open hole? is it threaded?
 
Hard to tell I believe it is just an open hole, I was going to drill and tap it, my only fear being drilling too far or deep but I guess that is what has to be done... it doesn't look threaded it's hard to see the old fitting was probably brokenoff in there
 
Ok so got it started yay!!!! But... I pull the throttle and it bogs down??? What is my next step I was so excited for this and atleast it is starting!!!
 
Ok so it didn't start after a couple times I gave it a small shot of starting fluid it started and the rpms were way up I pulled the throttle and it bogged down... so I am guessing my carbs are out of adjustment? How and what do I do there?
 
Starting fluid is not good for it. Mix a little gas and injection oil, and spray it into the inlet of the carbs. It just needs to prime the system, as long as you did the carbs correctly. You hooked up the pulse line to the mag side carb, correct?
 
As far as I know they are hooked up correctly, I got them off of a donor ski so I think they might be out of adjustment I let it sit for a little and it fired up and idled high, came down a little but still really high
 
It should idle at 3000 RPM. You can run it on the hose for a couple of minutes, but not longer or it will burn up the carbon seal on the drive shaft. And remember, start it, then water on, then water off, then shut it off. If you mess this up, start it up again immediately. Or you may have pumped water into the motor. Sounds like you are close though. Good job.
 
Wow 3000 rpm for idle I did not think it would be that high. Again all new to me.. I will test again tomorrow sometime if I get time, I also may have to adjust the carb for idle, if it stays high.. since the carbs were donors, they were shipped to me and might have got the screws moved or something but yes very close
 
You have to open the carbs and at least clean or rebuild them with genuine mikuni rebuild kits! Very important to do this step...., you got carbs from somewhere else and have no idea what's inside. They might be plugged up or dry and crusty. The carbs are the heart of these engines and if they are not right you will destroy your shiny new engine. Research on here on why and what needs to be done. At LEAST open and clean them!
 
+1 ^^^^^^^^ And the fuel lines need to be replaced as well if they are still gray. The fastest way to kill (about the only way to kill)* these motors is to run them lean. They need a perfect fuel system and the proper oil.

*getting water in them and not getting it out quickly will also kill them...
 
I did clean the carbs as they were pretty damn clean when I got them, I took them apart and cleaned them,. Everything seemed good, I figured I will rebuild them after this season
 
Just for a note, it will idle at 3000 on the trailer, but only 1500 in the water with the water load on the pump.
 
Ok so I am back again and still need help.... I finally took the carbs out cleaned them out replaced all the fuel lines... re adjusted the carbs to factory specs checked the pop off settings... got
Them back in and the Sea-Doo still just cranks????? I put some mixed fuel in the carbs it fired up and shit right off??! So I don't understand how I still have a fuel issue when everything is good? The only
Thing I can think to do is drain the fuel tank and fill it with fresh new fuel?? Other than that I'm at a loss and getting so annoyed I don't even want to work on it
 
Everything is not good....
As long as we got that out the way first.
Something wrong with fuel pump portion on carbs.Its not pulling gas into carbs. You have to check fuel lines also. Make sure they are in correct spots and fuel knob in ON position.
 
Like mano said, likely wrong plumbing. You can test it all by running a fuel line directly from the RES spud on the fuel baffle directly to the inlet on the carb. If that works, it is a fuel line issue. If it does not, you have something wrong in the carb, likely the fuel pump.
 
Ok so I figured it out, stupid stupid mistake, my fuel valve was turned off.... so now it fires right up... I just can't get my carbs dialed in correctly... here is the issue... it fires up on the trailer it is only idling at 1500.... when I know it should be around 3000... then I pull the throttle it bogs down and stalls... when I cleaned the carbs and put them back together I went with the factory settings and I know it will obviously vary.. but I was wondering which screw do I start with? And do I adjust both carbs to the same position?
 
Adjust the idle up to 3000 on the trailer. Use the idle adjustment screw not the mixture screws.
 
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