GTI LE RFI idle and low speed issues

[crazytiti]

Hello all, i'm new here with a 2003 seadoo GTI LE RFI i bought 2 month ago and i've ride it 3 times.
I'm facing bad idle and low speed.
Over 4k rpm it's seems fine (my first jet so no real comparison) and it top out at 6800 - 70km/h
I've made a video to help you help me ^^
What i've already done :
- check and clean RAVE valve
- check plug gap -> ok but the plug are BR9ES, i've ordred BR8ES they should come soon
- check and replace air t° intake sensor
- check water t° sensor
- check and clean injectors
- try to adjust idle screw (there's a screw on my 2003 model) it was worse so back to where it ran the better.
- set the oil pump to the mark at idle

You may tell me to reset the TPS sensor, but there's no shop around me to do that (i'm in inner france and jetski are rare)
So i may buy GreenHulk PWC Performance Store - CANDooPro Limited Sea Doo and Can Am ATV Home System (2 stroke 4 stroke) but only in last resort.

About my issues :
- at the start the idle is fine and smooth ~1800rpm then after few seconds it fall to 6-800 rpm very rough with misfires.
I can give a little gaz and it will be back for some seconds then fall again.
I can do WOT then it will be good for few second (up to 10s) and fall...
- the other issue is at low rpm and steady throttle (2 to 3.5k rpm) the motor is not steady sometimes it want to get another 500 rpm and goes back.
Above 4k rpm no problem.
I think top speed is fine because compression is a little low with 120psi on both cylinders.
Motor is said to have been rebuild and got 200hr then on fresh water.
The overall jet is in pretty good shape, nothing has been tampered with, all pieces look like OEM
The plug look like a little too black to my taste, maybe because 9 instead of 8 ?

 

[shamrock246]

I think the RFI’s drop a cylinder at idle not sure what year that started. What oil are you running these take a certain spec. If your planning on keeping the ski the Candoo pro might be a worthwhile investment and the equipment to test the fuel pressure. I think the BR9ES is a colder plug probably not helping things. The 1999 I worked on had voltage regulator issues and they make upgraded units not sure if the 2003 suffered from that issue. I would see if the fresh plugs make it smoother.

Good place for parts
https://osdparts.com/

 

[Seadoo Tuner]

Is that 70kph gps or on the Seadoo's gauge?

These are nice ski's when working well.

 

[crazytiti]

I read about the one cylinder idle, i have the service manual of the 2004 and it said that.
But the 2004 doesn't have the screw to adjust idle and tps is reset at idle position instead of close position.
I think mine should be idling on both ... ?
Yes BR8ES are the one that should be on it (i even have a sticker said that) i hope it will be better with it.
I checked the voltage when running ~3000 rpm and it's good (13.5)
70kph is GPS and the ski, i was surprised at what point it is accurate

Edit : I notice that max power is available at 50-60% throttle, going to 100% doesn't change much if anything.
I checked the throttle linkage and it's good, the throttle open 100% when i have the controller to the handle.
Is it usual ?

Edit : i just download the 2003 service manual and there is a screw to adjust the idle, the reset should be done with the plate totally close.
And the mention about idling on one cylinder is missing thus idle on both cylinder for 2003 rfi

 

[crazytiti]

Last WE i went skiing with my daughter
We spent roughly 1.5h on water

At some point she drives, and since she's ten and it's her first time on a jetski we were going slow (10-20 kmh)
After some times i get back to the handlebars put WOT, the jet was going as usual until soon it loose speed and was going at max 3200-3400rpm whatever how much i push the throttle (like a limp mode)
So we managed to get back to the pontoon at 10kmh and i put the ski on the trailer.

I get the plug out and they were as black as "usual" but one was dry (mag i think) and one was wet.
I think the wet one has fouled and we were going on one cylinder only.
Hopefully i will get the good plugs BR8ES tomorrow.
Waiting this time i have unbolt the head and have seen interesting things.
At first the pistons and cylinders seems very fine to me : small carbon deposit on piston dome, seems ok for 200hours.
The wall of the cylinders still have the honing marks
The mag one have some small vertical trace that you cannot feel with the finger nail.
But when i have cleaned (and a little sanded) the head i found trace of something that broke on MAG cylinder.
So i think the motor was rebuilt with new cylinder and pistons
They's also trace that i don't know what is it. It's like the continents on the earth..

I will put back the motor like this with the new plugs and hope it will be back on 2 cylinders.
What do you think about the head ?

 

[crazytiti]

I have reassemble the motor with brand new plugs BR8ES
The ski work like before : idle and low speed is erratic, after 3500rpm everything is fine.
After 45min i get it out of the water, the plugs are dark and the PTO one is still wet...

 

[burtshaver2021]

I hope someone comes on that has an idea what could be causing this issue. I just came to mention that extended running like this when it’s not running as it should can cause engine damage. If it ends up being a fuel shortage it will not be getting the lubrication it needs. When I’m working on one of these, when I take it out for a test run as soon as it has the slightest hiccup I get it home.

 

[crazytiti]

I hope too, it's not super critical or super annoying but it may foul plugs or else ... ?

 

[burtshaver2021]

I hope too, it's not super critical or super annoying but it may foul plugs or else ... ?

I’m just thinking if it’s fuel related it could damage the engine driving as it is

 

[shamrock246]

Have the injectors been removed and professionally cleaned? Is the oil pump adjustment set correctly? What oil are you running? Not sure if the lower compression is causing the combustion chambers to run at a lower temperature.

 

[crazytiti]

I have put the injectors in a bath of "injector cleaner" but i have not measured them.
The oil pump is at the mark, i'm using MOTUL powerjet 2 stroke from PO (see the upper pic)

 

[shamrock246]

According to the specs on the website that’s a TCW-3 semi synthetic which is the wrong spec. It requires a full synthetic API-TC, ie Seadoo XPS, Amsoil interceptor I’ve used both.

 

[burtshaver2021]

Yep, and I’ve ran TCW-3 in my weed trimmer and it killed it inside of a season. Didn’t realize it called for Sthil API-TC rated oil

 

[shamrock246]

Does anybody know if he mixes these oils that they might gel?

 

[burtshaver2021]

They can, best to drain the tank and lines and bleed out why can be from the oil pump. Can also put the 2 in a cup together fo a couple days to see what they do

 

[shamrock246]

That’s what I did with the seadoo xps and Amsoil Intercepter oil for a month and nothing happed. I’m going to go to Amsoil eventually.

 

[burtshaver2021]

Are you in the USA? I’m in Canada. I ordered Triax directly from their website, had it shipped to a parcel warehouse just 12 minutes from me in Ogdensburg NY. That was the least expensive oil I could get that met the API-TC and was low ash

 

[shamrock246]

I’m in the USA, I use Amsoil in everything I own and ran the intercepter in my 2000 Yamaha GP800 and XL800 with no issues.

 

[burtshaver2021]

I’m in the USA, I use Amsoil in everything I own and ran the intercepter in my 2000 Yamaha GP800 and XL800 with no issues.

I wasn’t saying Amsoil would cause any problems, just letting you know the Triax was the best price I could find for an oil that met all specs

 

[shamrock246]

I wasn’t saying Amsoil would cause any problems, just letting you know the Triax was the best price I could find for an oil that met all specs

No worries i didn’t think you were. I’ll check out Triax.

 

[Seadoo Tuner]

Are you in the USA? I’m in Canada. I ordered Triax directly from their website, had it shipped to a parcel warehouse just 12 minutes from me in Ogdensburg NY. That was the least expensive oil I could get that met the API-TC and was low ash

How much was the Triax in Canadian $ including shipping?

I used to use the Mystik JT-4 that I got at Canadian Tire for 39.99 for the 5L, but they don't carry it anymore. Last jug I bought was 2-3 years ago. Still have 2 liters left, but looking at Canadian Tire this week found they now carry Motomaster brand api-tc 4L for 69.99 cdn, pricey.

 

[crazytiti]

According to the specs on the website that’s a TCW-3 semi synthetic which is the wrong spec. It requires a full synthetic API-TC, ie Seadoo XPS, Amsoil interceptor I’ve used both.

Oh ! OK that's a clear statement i should change oil
Seems hard to know which oil is ok and available here in france (i check on amazon).
I ask chatgpt and it gives me 2 recommendation :
- motul 710 2t (2t stand for 2 stroke in french)
- castrol power 1 ultimate 2t
Castrol power is at 62€ 4L
motul 710 is at 59€ 4L

That's ~70$/gallon

I struggle to find another choice.
Do these seems ok to you ?

 

[burtshaver2021]

How much was the Triax in Canadian $ including shipping?

I used to use the Mystik JT-4 that I got at Canadian Tire for 39.99 for the 5L, but they don't carry it anymore. Last jug I bought was 2-3 years ago. Still have 2 liters left, but looking at Canadian Tire this week found they now carry Motomaster brand api-tc 4L for 69.99 cdn, pricey.

I paid 8.50 to cross the bridge and another 7.00 at the parcel service. 97.31 would be close to 140.00 CDN. So all in around 155.00 CDN. fo the 4 Liters