new to PWC's. Need help

[MustanGTyler]

I just purchased my first Seadoo. It is a 1998 GSX Limited. the engine has been replaced with the more reliable silver version. I'm having a problem getting it to run correctly. It will start up and run for about a minute then shut off. it runs fine then just bogs down and shuts off. I'm getting the "12v low" and caution light when i start it up. The compression is 130psi on both cylinders. The previous owner had the carbs rebuilt at a shop and they set the low speed adjustment to 1 1/4 turns out and the high speed to 1/4 turn. He told me the ski had weak spark when I bought it. I trimmed back the spark plug wires and checked all grounds and the spark looks okay to me. can anyone point me in the right direction on what I need to do to get this ski running? could it be the mpem? thanks

 

[6KJR]

Probably carb related. Do some reading and you will learn a lot in a short time. All these older machines have the same problems. Grey fuel lines, need carb rebuilds, etc. Not to often you hear of MPEMs going bad. Its the other things like coil, crank pickup, stator....

 

[MustanGTyler]

Thanks for the reply! carbs were rebuilt last month. The previous owner was able to produce receipts proving so. Gray fuel lines have been replaced with Good Year hoses and the coil was also replaced. Tomorrow I plan to buy a voltmeter and test the ski running and when shut off. Also, I've read about unplugging a red wire to test the rectifier. Where is this red wire located exactly? I've also heard about unplugging a fuse and starting the ski to test it. Any info on this? Your help is greatly appreciated!

 

[Dr Honda]

Thanks for the reply! carbs were rebuilt last month. The previous owner was able to produce receipts proving so. ...... Your help is greatly appreciated!

So?!!?!

OK... he showed you a receipt, but who knows if the moron mechanic did it right... or half ass'ed. Was it water tested after the rebuild??? You wouldn't believe how many carb issues I fix every summer AFTER the local dealer "Just rebuilt the carbs."

Carbs need to come off, and EVERYTHING needs to be verified. The ski is new to you... so don't assume anything if you want it to run. Honestly... it's best to forget anything the last owner told you, and just start working.

I'm not trying to be harsh... I'm just saying the truth.


After reading your fist post... I would say

1) The fuel select valve is plugged... OR
2) The internal filters are plugged... OR
3) The fuel lines are hooked up wrong.

 

[MustanGTyler]

I'm going to take your advice and pull the carbs and start from scratch. couple of questions about the adjustments screws. where is the idle adjustment located? and i see the high and low speed adjustment screws but which is which? (ie: high speed on top of carb) also, I hooked the battery up to a voltmeter today and found the voltage to be ~12.0 when not running and between 10 and 12 volts when running. So I'm going to order a new MPEM tonight.

 

[brock1]

I'm going to take your advice and pull the carbs and start from scratch. couple of questions about the adjustments screws. where is the idle adjustment located? and i see the high and low speed adjustment screws but which is which? (ie: high speed on top of carb) also, I hooked the battery up to a voltmeter today and found the voltage to be ~12.0 when not running and between 10 and 12 volts when running. So I'm going to order a new MPEM tonight.

What makes you think that you need a new mpem just beacuse you show low voltage does not directly mean your mpem is bad

 

[MustanGTyler]

well, i don't know that for sure. I took it up to my local dealer today and asked them to look at it. the technician told me they have had several up there recently that had bad mpem's. It's just an assumption really. What sort of tests can I do to find out exactly what it is that's causing the problem?

 

[Dr Honda]

You idle screw is on your MAG carb, in line with the throttle arm. (where the cable hooks to)

OK... your not charging. 9 time out of 10... it's the regulator. AND... in Seadoo's infinite wisdom... I think your ski has the internal regulator. Your MPEM is super expensive... so... if you are good with wireing... you can just install an external regulator from an RFI ski. If you need electrical help... you can buy an external kit.


You can find it here

 

[chapmangsx]

!998 seadoo gsx l

Hey guys sorry to just jump the thread but as the gentleman who started the thread im kinda having the same issues.. carbs rebuilt and everything is verified good but i had an oil leak so i took my carbs off only to verify that my low speed. The screw on the bottom of the carb.. Were set to 3 1/4 turn.. i twisted both in three and a quarter and put them both back to were they were originally. now my only concern is not with the oil leak but the carb adjustments...

it used to have the white motor. motor swap to silver using the white exhaust, mag/strator/oil pump and white engines carbs...

What the heck should i do... just adjust them to what specs say ?

 

[MustanGTyler]

Thanks for the link. I'll pick that up instead. now i just have to get the carbs off. I worked forever trying to get the mag side top carb bolt off. still can't get it. I'll have to finish up tomorrow. But in the process of replacing the battery, I pulled one of the hoses that runs to the water outlet that's behind the tow ring on the back of the ski. i'll have to take a picture of it tomorrow to help explain my situation. again thanks for all of the help thus far.

 

[Dr Honda]

Hey guys sorry to just jump the thread but as the gentleman who started the thread im kinda having the same issues.. carbs rebuilt and everything is verified good but i had an oil leak so i took my carbs off only to verify that my low speed. The screw on the bottom of the carb.. Were set to 3 1/4 turn.. i twisted both in three and a quarter and put them both back to were they were originally. now my only concern is not with the oil leak but the carb adjustments...

it used to have the white motor. motor swap to silver using the white exhaust, mag/strator/oil pump and white engines carbs...

What the heck should i do... just adjust them to what specs say ?

Depends on what carbs you have. Your needle settings are going to go with the internal jetting. BUT... I can tall you this... after about 2.5 turns out... the needle doesn't do anything.

 

[chapmangsx]

So would you just suggest a rebuild with proper setting or is there a way to identify the carbs in aspect to know what im dealing with to look it up, im sure they came off the old white motor seadoo and theres just a bolt on replacable like the rest of the parts. mag. exhaust and so on. im thinking imma take em in to a seadoo dealer and get em rebuilt to specs... i hope. theres a thread for the 787 carb rebuild.. but the 947 carbs look a bit different. is there a tread kicking around for a 947 rebuild.. or same deal just a different hose in a different spot

 

[MustanGTyler]

I finally got a chance to get the carbs off and cleaned up. I'm about to order the external rectifier harness and some new gaskets. I noticed today that I had a hose that was unplugged and I'm not sure where it's supposed to go. One end is connected to the right hole on the back of the ski that I have pictured below. can anyone tell me where the other end goes? thanks

 

[Seadoobuddy]

Hi, sorry to jump in. I have a 96 GTX. I learned one thing this week after joining and reading stuff online. 1. I was not affected by the 94-96 gas tank recall.
But what is the the difference between a white and silver engine??? I have white. Is the silver a replacement for certain yrs?.

The line you asked about probably goes to a pick up somewhere to shoot water out the back to let you know water is circulating.....

 

[Dr Honda]

That's the pee-hole to see if you have water flowing. The hose should be hooked to the head pipe.

 

[MustanGTyler]

UPDATE:

Just wanted to let everyone know that I haven't fixed the ski yet. I ordered the external rectifier that the Doc prescribed. it will be here today and I already have a new gasket kit so I will start putting everything back together this evening. I'm really hoping this fixes it but if not, where do i go from here? stator? Also, I looked up a schematic of the pee hole lines. I found that the white engine used both of the pee holes and the silver uses only one. That explains why I only have one hose hooked up. So, once I get everything reassembled I'll give another update and let you all know where it stands. Thanks for all of your help thus far.

 

[bmocken]

the silver one has two pee holes with tubes to both. One runs by the airbox latch and the other is ontop of the exhaust manifold.

 

[MustanGTyler]

everyone I've talked to has told me that. But i found this diagram in the online manual and this is how my ski is set up. Is this acceptable?

 

[MustanGTyler]

I also found this diagram on a website. It shows the hoses routed the way most people have been telling me it should be. I see that there are two models of the 1998 GSX limited. the first diagram I posted shows the 5625. this diagram shows the 5629. Can anyone explain this to me?

 

[bmocken]

what color is your ski?

 

[MustanGTyler]

it's gray and red with purple trim

 

[bmocken]

I also found this diagram on a website. It shows the hoses routed the way most people have been telling me it should be. I see that there are two models of the 1998 GSX limited. the first diagram I posted shows the 5625. this diagram shows the 5629. Can anyone explain this to me?

[/QUOTE
what color is your ski? If you replaced the white motor with the silver one and kept the old exhaust manifold than you may only have one line. I have a 98 GSX Limited that is the Red and Purple model that has the silver engine in it and there are two lines as shown in the lower diagram. The top diagram doesnt match my silver engine the lower one does and it shows the line out of the top of the manifold going to the left hole and the line the goes to the hole on the right is located by the bolt that screws into the exhaust that holds the airbox latch. Standing on the side where the airbox is , look at the exhaust manifold and follow it to the right. You should see a tube going into the exhaust and if its not hooked up you should either see a hole or a nipple where the hose should slip onto. There is a bracket that holds the airbox on mine that has three allen bolts that hold it on two right above the carbs but under the exhaust and one that is a bolt sticking out the right side if the exhaust. I dont have my ski at home so I cant take a pic to show you but that is where that line goes. Where is the line that is at the top of the manifold going?

 

[MustanGTyler]

I have the silver engine but the white manifold, stator cover etc. On my ski, the line that is at the top of the manifold is going to the water valve on the exhaust. I will take pictures of everything tomorrow if i need to.

 

[bmocken]

Circled in red is where that line should go if the top line goes to a pee hole:

Since you said it goes to the water box and you have the old man1312429866ifold that line should be in the same place:

 

[djredman99]

I also found this diagram on a website. It shows the hoses routed the way most people have been telling me it should be. I see that there are two models of the 1998 GSX limited. the first diagram I posted shows the 5625. this diagram shows the 5629. Can anyone explain this to me?

Seadoo first introduced the 951 motor painted white in the 1998 GSX Limited (5625). This is the gray top deck, red hull, read seat, and purple trim ski and is sometimes referred to as the 1997.5 GSX Limited. They didn't produce these skis for very long until they then shipped the 98 GSX limited (5629) with a silver 951 motor, red top deck, red hull, purple seat, and purple trim.

I have a 5625 GSX Limited...its the ski in my avatar.