96 GSX bogging at 3/4 to full throttle

[nwscoobie]

I just picked up this ski from a guy that just sells stuff he trades. So he did not have really any history on the ski. He said the fuel is a year old and it runs.
It looks like the coil was replaced with a wsm and it has great spark and compression the ski has 139 hours. I am not sure how long it has been sitting. But here is the issue.

It starts right up within a second without choke. When in the water it goes good up until about half to full throttle it looses power and bogs down. If I let off right away it will idle down and not die. Then as I punch it again it re occurs. When I first took it out it would die every time after the bog, now it seems to be a little better. To me it seems to run better with the seat pulled back and it takes longer to bog.

Yes it has gray lines, so does my other ski that runs perfect and my buddies has gray lines as well and runs fine.

The fuel selector seems to spin freely and does not stop turning, it does hold it position though.

I pulled the fuel line going to the carbs and it has fuel, I even dumped the filter a couple time so it is sucking in fuel.

I know replacing the lines and fuel are a proactive step, I just want some advice before I start tearing down the carbs and fuel lines.

Could it possibly be a highspeed screw? Does anyone know the stock turns for them? It seems I cannot find a full manual on this ski.

 

[ricardo1]

I just picked up this ski from a guy that just sells stuff he trades. So he did not have really any history on the ski. He said the fuel is a year old and it runs.
It looks like the coil was replaced with a wsm and it has great spark and compression the ski has 139 hours. I am not sure how long it has been sitting. But here is the issue.

It starts right up within a second without choke. When in the water it goes good up until about half to full throttle it looses power and bogs down. If I let off right away it will idle down and not die. Then as I punch it again it re occurs. When I first took it out it would die every time after the bog, now it seems to be a little better. To me it seems to run better with the seat pulled back and it takes longer to bog.

Yes it has gray lines, so does my other ski that runs perfect and my buddies has gray lines as well and runs fine.

The fuel selector seems to spin freely and does not stop turning, it does hold it position though.

I pulled the fuel line going to the carbs and it has fuel, I even dumped the filter a couple time so it is sucking in fuel.

I know replacing the lines and fuel are a proactive step, I just want some advice before I start tearing down the carbs and fuel lines.

Could it possibly be a highspeed screw? Does anyone know the stock turns for them? It seems I cannot find a full manual on this ski.

Get rid of the old gas and put fresh gas
Change the spark plugs
CHANGE THE FUEL LINES ASAP!!!
Change the fuel selector it's 20 bucks
What is the exact compression on each cylinder?
Not too familiar with highspeed screw but someone will shime in.

 

[Seadoobuddy]

Once you change the gray line to black, please clean or replace the little filter in the carbs. they are probably getting gummed up from old gas varnish & the green goo the forms with the old gray lines. The carbs are not supplying enough gas to the motor to keep it running at max RPM so replace, clean and replace the fuel selector too.
Also would be a good idea to add an in-line fuel filter too. A Fram G-2 works great in these skis.

Don't risk running lean to save a few bucks or hope the problem clears up with more running time.....it won't.

 

[CReynoldsMIZ]

Yes it has gray lines, so does my other ski that runs perfect and my buddies has gray lines as well and runs fine.

That is basically saying, " I am skinny and eat mcdonalds every day so ill just continue to eat it because nothing bad will ever happen to me".

Get rid of the fuel lines. Clean the carbs (100% must) and why your ski is bogging probably, and replace or clean the fuel selector.

Replacing the lines and cleaning the carbs isnt a proactive step. It is almost certainly your problem

 

[nwscoobie]

Thanks guys, I will go ahead with those lines its only like .65 a foot. I was going to add an in-line filter as well. The fuel selector seems to be working if fuel is going through the line and being pumped but I will at least clean it out.

I will have to remove the carbs to clean the screen inside correct? My 95xp would die at high speed but eventually cleared itself out. After running my gsx it does not seem to be the same as the XP

Does anyone know the low and high screw positions? Also how many hose clamps do I need? I want to get everything when I get off work.

 

[CReynoldsMIZ]

Here is what you need. Like 25' to be safe of the 1/4" fuel line. I think like 20 or so of the fuel clamps. Grab two cans of carb cleaner. The high should be 0 turns, and the low I think was 1 turn out. They say dont clean out the fuel screens in the carb with fuel cleaner, but with just water and soap if you can. Also whenever you clean the carb parts dont get the carb cleaner on any rubber parts

 

[nwscoobie]

Here is what you need. Like 25' to be safe of the 1/4" fuel line. I think like 20 or so of the fuel clamps. Grab two cans of carb cleaner. The high should be 0 turns, and the low I think was 1 turn out. They say dont clean out the fuel screens in the carb with fuel cleaner, but with just water and soap if you can. Also whenever you clean the carb parts dont get the carb cleaner on any rubber parts

Ok great, thanks for the info. I will update this when I get everything cleaned up. I also have to install my kicker kicker stereo into this boat. I wish I had the 787 is my 95xp would that be too much work?

 

[Luv2Camp]

I would go ahead and replace the fuel selector. It would SUCK to do all of the work, take the carbs off and apart to clean/replace the filters and only have them gummed back up due to the sticky residue that is coming out of the selector valve if you did not get it all out. My 1995 ski had only 100 hours on it when I bought it last year and the screens in the carbs were half full and all of my lines were gooey when I took them off to replace them.

 

[pags1220]

http://www.sudco.com/Diagrams323728/expbn.gif here's a breakdown of the carb if you need this info.

 

[falklandsx]

Ok great, thanks for the info. I will update this when I get everything cleaned up. I also have to install my kicker kicker stereo into this boat. I wish I had the 787 is my 95xp would that be too much work?

Yes, major surgery. The "bolt-in" motor swaps (at least the ones that I am familiar with) fall into two categories:

587, 657, 657x, & 717, or

787 & 951.

a 787 motor in the later revision of the 95 XP hull you have is the X4 platform. To be clear, it's a different platform, but from a distance, the two look similar. Do a bit of searching and you'll find that the X4 platform has a cult following, and many of the X4 junkies (myself included) probably need professional help Sell the 95XP and get one of the x4 skis if you want a 787: 1995 XP800, 1996 XP, 1997 to 1999 SPX.

Now to your gsx. If the ski runs fine up to 1/2 throttle, it's probably an issue in the high-speed circuit. For your ski, the HS screw is set to 0 (all the way in) and the LS screw is set to 1 turn +/- 1/4.

Couldn't agree more with the previous comments, replace the fuel lines, the fuel selector, and get a rebuild kit for the carbs. Drain the fuel, pull the fuel tank and clean it. Also, pull the oil tank and drain it unless you are sure what injection oil was being used.

 

[nwscoobie]

http://www.sudco.com/Diagrams323728/expbn.gif here's a breakdown of the carb if you need this info.

Thanks, I had to look at this a couple time but got it all straightened out.

Yes, major surgery. The "bolt-in" motor swaps (at least the ones that I am familiar with) fall into two categories:

587, 657, 657x, & 717, or

787 & 951.

a 787 motor in the later revision of the 95 XP hull you have is the X4 platform. To be clear, it's a different platform, but from a distance, the two look similar. Do a bit of searching and you'll find that the X4 platform has a cult following, and many of the X4 junkies (myself included) probably need professional help Sell the 95XP and get one of the x4 skis if you want a 787: 1995 XP800, 1996 XP, 1997 to 1999 SPX.

Now to your gsx. If the ski runs fine up to 1/2 throttle, it's probably an issue in the high-speed circuit. For your ski, the HS screw is set to 0 (all the way in) and the LS screw is set to 1 turn +/- 1/4.

Couldn't agree more with the previous comments, replace the fuel lines, the fuel selector, and get a rebuild kit for the carbs. Drain the fuel, pull the fuel tank and clean it. Also, pull the oil tank and drain it unless you are sure what injection oil was being used.

Thanks for the info, I was sure It was harder then it looked. I adjusted the screws as well they were at factory specs. Luckily the carbs did not need a rebuild kit everything was ok inside. The screen looked a little gummy but overall they were good. I still removed everything cleaned and soaked with cleaner.
I replaced all the fuel hoses as well. I left the vent hose in because it was late and I did not see a point in doing so. I added an in-line filter.

So the tank was full of fuel that was older and I decided to drain it and I am glad I did. It was dark brown and gross, I filled a 5 gallon jug and 2.5 jug. Such a waste of fuel when and filled it up with new fuel and took like 60 to fill this thing... After I got fuel I went back home to see if it would start, it was past 10 so I could not rev it up.

If anyone had to choose between the two ski's which would be the better choice to own? I like how small and fun the 720 is but I'm full throttle all the time and sucks down the fuel trying to keep up with my buddies spx. He can pass me slow down and pass me again I am leaning towards the GSX it can still be a little tippy but not too bad and has the larger motor so I can keep up. I plan on removing my stereo from my XP and installing it into the gsx. How much would the XP be worth? I would rate it a 7 out of 10 on overall condition I have a shorelandr trailer for it too. I really like to spin on the xp.

 

[nwscoobie]

I would go ahead and replace the fuel selector. It would SUCK to do all of the work, take the carbs off and apart to clean/replace the filters and only have them gummed back up due to the sticky residue that is coming out of the selector valve if you did not get it all out. My 1995 ski had only 100 hours on it when I bought it last year and the screens in the carbs were half full and all of my lines were gooey when I took them off to replace them.

I let the fuel selector soak and I cleaned it out pretty good with cleaner. I will buy a new one, just need to get by with this one for now. I had a hard time trying to get the plastic nut on the fuel selector with the plastic ring with the indicators on it. I eventually just said screw it and just put the nut on the fuel selector and the knob on.

My screens in the carbs had very minimal goo in them.

 

[Spimothy Leary]

Thanks, I had to look at this a couple time but got it all straightened out.




Thanks for the info, I was sure It was harder then it looked. I adjusted the screws as well they were at factory specs. Luckily the carbs did not need a rebuild kit everything was ok inside. The screen looked a little gummy but overall they were good. I still removed everything cleaned and soaked with cleaner.
I replaced all the fuel hoses as well. I left the vent hose in because it was late and I did not see a point in doing so. I added an in-line filter.

So the tank was full of fuel that was older and I decided to drain it and I am glad I did. It was dark brown and gross, I filled a 5 gallon jug and 2.5 jug. Such a waste of fuel when and filled it up with new fuel and took like 60 to fill this thing... After I got fuel I went back home to see if it would start, it was past 10 so I could not rev it up.

If anyone had to choose between the two ski's which would be the better choice to own? I like how small and fun the 720 is but I'm full throttle all the time and sucks down the fuel trying to keep up with my buddies spx. He can pass me slow down and pass me again I am leaning towards the GSX it can still be a little tippy but not too bad and has the larger motor so I can keep up. I plan on removing my stereo from my XP and installing it into the gsx. How much would the XP be worth? I would rate it a 7 out of 10 on overall condition I have a shorelandr trailer for it too. I really like to spin on the xp.

Although the xp 717 would be considered generally the more reliable power plant, i'd say keep the GSX with the 787, that little bit of extra speed does help, especially if you ride with faster ski's,and as time goes by, unless your ski runs high 50's at a minimum, everybody will be faster, except the baseline models.

If your constantly pushing WOT to keep up, it will wear down an engine pretty quick and shorten the life span. I recommend keeping WOT runs short and sweet, less than a minute, preferably 30 seconds. Back when I had my 49mph Yami, I was always pushing WOT to keep up with the 60mph ski's, and I burned through two top ends over a 3 year span, not fun.

 

[kicker]

My 95xp would die at high speed but eventually cleared itself out. After running my gsx it does not seem to be the same as the XP

Here is the danger with these things. When any of your skis are hesitating, bogging, etc chances are it is either from too much fuel or not enough. Most of the time it is the lack of fuel, especially when the symptoms show up at more then half throttle. In this case, your ski is not clearing itself out, it is finally getting the fuel it needs to run properly.

The fuel itself has a huge part in the lubrication and cooling process, when trying to force them to "clear up", more then likely you are running extremely lean and hot for that period of time. This could result in a slow death or quick death of the motor.

My advise is when it is not running right, dont push it, go easy, get back to the dock and figure out what is wrong before it grenades.

Ohh, and 787 GSX is my choice.

 

[nwscoobie]

Here is the danger with these things. When any of your skis are hesitating, bogging, etc chances are it is either from too much fuel or not enough. Most of the time it is the lack of fuel, especially when the symptoms show up at more then half throttle. In this case, your ski is not clearing itself out, it is finally getting the fuel it needs to run properly.

The fuel itself has a huge part in the lubrication and cooling process, when trying to force them to "clear up", more then likely you are running extremely lean and hot for that period of time. This could result in a slow death or quick death of the motor.

My advise is when it is not running right, dont push it, go easy, get back to the dock and figure out what is wrong before it grenades.

Ohh, and 787 GSX is my choice.

It was probably not the best idea but I was impatient and I pretty much got the ski for free so I just went for it.


So I rode the GSX for 2 hours today without any bogging or dying. Started right up, I was impressed with myself for taking everything apart and routing new hoses without any issues.
The rear carb was a little on the dry side judging from the plug, I turned the rear high screw out half a turn and that did the trick. The boat will barely hit 50 on the calm water is there anything else I should check? I know it is a little bigger but I feel like it should have a little more power hitting 6920rpm WOT. Maybe a new impeller? Would mine off my 95xp interchange?

 

[jammin777]

the 787 gsx should go 55 to 57 mph, your rpms are right. it could be the impeller or maybe some cavitation going on?

 

[kicker]

Your rpm's are bang on, so you should be running 55 ish, my guess is the speedo is a little off and your going faster then you think. Try it again with a gps if you can.

Unless your impeller has a good amount of damage it's probably not the issue or worth changing. A few nicks on the leading edge is fine, all mine have nicks in them but still hit 55ish. Check the gap between the impeller and wear ring, it should be less then 1mm.

 

[nwscoobie]

I did use the gps on my phone and its pretty accurate with my truck. 50 was pushing it it mainly hung around 47-48 mph, I weigh a good 180. It does cavitate a small amount out of the hole. Its probably time for a new impeller, I will have to take a picture of it. I went on a 14 mile trip and I need more speed.

 

[kicker]

Measure you wear ring gap, sounds like your loosing some traction.
If there is cavitation most of the time its the wear ring or carbon seal on the driveshaft.

Sent using Tapatalk

 

[nwscoobie]

Here are some pictures I took tonight. Does the ring look good? I think the impeller is a little chewed up huh.

 

[kicker]

That prop will cost you some traction and mph for sure. The wear ring looks marginal but ok, it is hard to tell from a picture, any gap bigger then a mm will start to cause problems. Honestly, because you have it out and apart, get the prop rebuilt or buy a new one and change the wear ring.

 

[nwscoobie]

Yeah the spacing looks ok, I am going to grind down the impeller and see if I can recover some power. Also the plastic guide right before the impeller has a piece of plastic that was broke and I am pretty sure that is where most of the loss was from. It was like wedged up and water would push against it kinda like a brake. Some JB weld fixed that issue.