two 1998 GTX LTD with a couple problems

[Triorieel]

My History
=======
I purchased 2 1998 gtx ltd seadoos last summer (2016) at different times from different sellers.
Wanted the same so I only had to learn 1 design and to have swap-able components if required (in the end they used a different pump shaft).

seadoo1 (purchased mid summer):
-Replaced all the fuel lines (except the small one between the carbs, my hands couldn't fit in there)
-Repaired the fuel sensor by bypassing internal fuse and installing a new one outside of the fuel tank
-Replaced the pump seal with the needle bearings.
-Requires some scratch repairs
-New spark plugs
-New battery
-On the final outing, the Seadoo hit a wave and popped the 15A fuse. I have found that one of the stater windings is shorted to ground. (my understanding is that I have to take apart the housing and clean metal shavings to fix. Seadoo won't run or start with stator disconnected)
-Does about 58mph with me on it with compression ~130


seadoo2 (purchased late summer):
-Requires Fuel line replacement
-Bypassed the Fuel sensor and will repair it as I did with seadoo1 when I replace the fuel lines.
-Requires some scratch repairs
-Installed new seat covers
-Cleaned and di-elctric greased connected on mpem (which was causing an incorrect disconnect with the key)
-New spark plugs
-New battery
-Underseat plastic has a large crack running down it lengthwise in the center (Tried melting plastic together with no luck)
-I have to slightly hold throttle to not let it stall (figure this is a carb setting)
-It has a dead rpm range. The rpm cant be set between 3500rpm to 4500rpm (might not be exact rpm range). It will jump to 3500 then 4500 then 3500 every couple seconds while holding the throttle still (I think about 60%)
-Does about 50mph with me on it with compression ~125


Questions:
Seadoo1:
1A) will cleaning the starter/oil housing fix my stater shorting out problem?
1B) Am I correct to notice that no stater = no spark?
1C) This seadoo takes twice the effort to cold-start in comparison to seadoo2. Ive tried adjust spark plug gaps to no avail. I worry about burning out the starter. Is this just the nature of the beast?

Seadoo2:
2A) I have never adjusted a carb, is the dead rpm range a carb problem?
2B) It also looks like there may be an exhaust leak under the big 10"ish exhaust clamp. could this be part of problem 2A?
2C) What would be suggested to repair the crack in the seat plastic. It works as it is, but I was thinking maybe riviting a plate with glue.

 

[mikidymac]

You need to get the carbs off and rebuild them with genuine Mikuni parts. Nothing will kill one of these engines faster.

The only way to know if the stator is bad is to test it then inspect it.

Exhaust leaks at the head pipe will also kill a 951 and seadoo made an update kit with a spray deflector "diaper ".

Stop running the ski that has the flat spot as typically it is running lean from a dirty fuel system and will seize the pistons.

Contact Minnetonka4me here and he can hook you up with a good used plastic piece instead of rigging the old one. He also sells the carb kits.

 

[Triorieel]

I lack experience with carburetors AND seadoos.

so heres my update. I keep reading different idle settings ont he forums from 1100 to 1500 in water. Seadoo1 runs at 1150 which sounds nice to me, but not sure.

Seadoo1:
-it was popping fuses because of metal pieces inside the magneto area. cleaned out and it runs great again. I couldn't figure out where these pieces came from. Does anyone have any idea? (far left piece looks like a piece of a gear tooth, no idea on the next piece, the remaining two piece are the same)


Seadoo2:
-replaced all fuel lines
-rebuilt the carb and set high and low as described for my seadoo from seadoosource
-fixed exhaust leak
-cleaned stator area to be safe (it was already clean)
-carb needs adjusted. If I slowly increase throttle it seems to by fine, but a quick throttle and it dies as in video. I am assuming this requires the high adjustment on both carbs. How do you know which carb or both? I would also like a smoother idle, but maybe this is normal?

[video=youtube_share;Wifr3YIN8wU]https://youtu.be/Wifr3YIN8wU[/video]
(I had the idle adjusted a bit higher at this point, but still unsure where it should be. It seems to move pretty fast at this idle when in forward)

I would appreciate some wisdom as this is probably fairly routine to the regular.
Thank you

 

[Triorieel]

I can't seem to edit posts.

I took seadoo1 for a water test. very disappointed. It ran ok in the channel (with some splutters. ie running at 1200 and occasionally spikes to 1400). When I hit open water and hit the throttle it felt weak compared to last year and could only get to 30mph (~4500rpm). It died after I did 2 circles (I didn't want to take it far as I don't like paddling). It started within a minute and I idled back to base. I'm not sure if this was electrical, bad gas, something else...I dunno.

I can't tell if seadoo2 is hesitating or bogging. You can also hear in the video it sounds weird when I touch the throttle and gets worse when I touch it a bit more.


I bought these, used them a few times and had to winterize. Am I having bad luck or is this normal for seadoos?

 

[mikidymac]

Well if you had a carb issue which is most likely and kept running it especially with it dying then you probably seized it. The 951's will not tolerate running lean at all.

 

[Triorieel]

Two seadoos.

seadoo1 was running fine. Then failed in the fall because of metal in the stator. I hit a wave and it would not run, or start after that. Would just immediately pop fuse. As the temperature was already cold from winter approaching I decided to just winterize it and deal with it now in warmer weather. I removed the metal bits and it now runs again...but only runs at 30mph. The picture shows the metal bits I removed.

seadoo2 had a flat spot in the rpm. Again, this was picked up close to winterization time, figured it was a carb issue so decided to deal with next season (now). I rebuilt the carb with the suggested settings and now it needs properly adjusted (which I have never done before). And hopefully that is all it needs and when I go to test it after the adjustments the flat spot will be removed. I am not sure if it is 'hesitation' or 'bogging' so the video is for someone with experience to enlighten me. Also if they see anything else suspicious.


Today is the first time they touched the water since I winterized them last fall. That is because after I did the work and tested them in the driveway, it was time for water adjustments/tests.


I am not sure where you think I ignored the symptoms and kept running the seadoos...

 

[jjsinaz]

Did you happen to read through Bill86 carb adjustments thread in the stickies section at the beginning of this forum> If not, then go ahead and take a look at that, then go through the carbs again. Two things that are especially critical 1) pop off pressure, 2) make sure the transfer ports (3 very small holes in the carb throat) are clean. Dirty transfer ports will contribute to having "flat" spots

 

[mikidymac]

When you say it only did 30 and had bad flat spot and bogging is when you kept running them.
Ski1. The metal pieces are not obvious to me so you need to open it up and actually find out what is broken. They obviously broke off from something.
Ski 2. You have a huge problem, probably fuel related if it only runs between 1200 and 4500 rpm then dies.

I would first start with a compression test on both skis first then report back.

1. One spark plug out.
2. Plug wires grounded.
3. Fully charged battery.
4. Throttle wide open.
5. Crank until needle stops climbing.
6. Repeat on other cylinder.

 

[jjsinaz]

Here's something else you may find helpfulView attachment sbn_manual.pdf

 

[Triorieel]

Thank you for responses,

jjsinaz, I didn't read that specific literature, but the instructions looks almost copy/paste from what I have read. This does have a nice breakdown of components.

I have replaced all diaphrams, filters, needles, springs, gaskets inside both carbs. I do not know if flat spot still exists as seadoo has not left the dock because of symptoms shown in video. I am assuming that I am currently facing the final carb settings.
1) I did do the pop test, it was a bit higher then what I wanted, but I read to not mess with the spring. Both carbs were popping somewhere between 23 and 25 psi(I read I should be 19 to 23 psi but have seen other people having higher). all 4 setups did the same (the 2 old and the 2 new needles/springs setup)
2) I am not entirely sure which specific ports you are referring to, but I did clean the individual carb parts, holes, filters, jets, etc...



mikidynamic:
the max 30 that was experienced today is a different ski then the one with the flatspot.

recap:
ski1 ran good. ski1 had debris in stator area and blew fuse. cleaned out debris. now only runs at 30. (keep in mind it sat over winter before I worked on it)
ski2 had flatspot. rebuilt and cleaned carbs on documentation I found on google. video shows its current state (still on trailer on ramp in water). I hope this is just the on water carb adjustment stage (I don't know if that is considered hesitation or bogging. I think it is bogging).


I did the compression test in the fall just before winterization.
seadoo1: roughly 130psi
seadoo2: roughly 125psi
I can't remember the specific pressure of each cylinder but I remember both skis cylinder differences were no further apart then 5psi.
It is predicted to rain pretty hard for the next 4 days, so if you want me to re-run the tests, it may take me a while (I work outside).

ski1: I tried finding where the pieces broke off from. I was using a snake camera etc... The gear piece might match one of the gears on the starter, but I couldn't see any broken tooth on the starter.
ski1: the max 4500rpm seen today was on ski 1. This surprised me as this seadoo ran fine up until the metal debris shorted out the fuses. I tested the windings after cleaning out debris and they came back roughly 1ohm between all 3 wires and no longer ground out. I'm not sure how this problem led into my current problem with limited power. or if its a new problem left over from winterization. I didn't see any debris (weeds) on the grill. Should I be trying seafoam (maybe some old gas dried up)?

 

[jjsinaz]

After taking a closer look at those broken metal pieces you removed from the stator area, I agree with Miki, you really need to figure out where those came from. Something is failing and you need to know what it is before more damage is done.

Seafoam is not recommended for two strokes

 

[Triorieel]

I know the left piece matches up with the gears on the starter (I just don't see the specific part that is broken, as it works, has no slip and can't lead into the 30mph problem, I'm not currently worried about that piece).

The pieces that worry me the most are the 2 right unknowns. I spent more then half an hour int he engine trying to find where they came from and couldn't. It can only come from magneto, stator, starter or magneto sensor as there is nothing else in the enclosed area. I checked all of them with no luck.
When I inspect the 2 pieces, they look like the are electrical wire holders. They are not broken (no broken edges. they appear to be clean whole pieces).
As it is harder to find pieces places, this is what lead me to bringing the picture to the forum in hope of someone else knowing.
The one piece was found inside the magento/stator area, the other I'm not 100% sure.


I have been looking at rebuild videos all morning in case I overlooked something when I was inside the engine. I have had no luck. I have seen some pretty clear take down videos can see no indication of where they come from (including complete starter motor tear down incase it somehow came from inside the starter).

I am starting to wonder if the previous person that worked in there let these metal parts in (previous person had some engine work on it before I bought it). That was also the first wave (and it was only a 2 foot wave) I hit that did it (so if it was loose, it would have been the first knock to put it into the shorting position).



As for the other seadoo, I'm going to do the same thing I showed in the video but pull the choke 1/2 way to see if the symptoms change. I read that could tell me if it is lean/rich (which makes sense).

 

[Triorieel]

When I did the pressure check last fall, I don't think I did the full throttle and/or kept a spark plug in the other cylinder.
As the 20mm of rain that was predicted to fall today hasn't, I redid the pressure check as per your exact instructions.

Seadoo1:
Battery Voltage (12.93v)


Plugs (did the quick water test followed by the 5min low wake home,sat overnight)


Mag PSI (~142psi)


PTO PSI (~142psi)


Seadoo2:
Battery Voltage (12.53v)


Plugs (seadoo hasn't done anything except idle 10 feet from trailer to dock)


Mag PSI (~145psi)


PTO PSI (~143psi)



Note:
All spark plugs have less then 2 hours on them.

I did the same test again on seadoo2 with 1/2 choke, and it felt much better (but engine wasn't warm yet)...so maybe its getting too much air.
How do I know which carb or both to adjust?

 

[Triorieel]

I guess I will just start turning the adjusters until it feels better. I wouldn't be so anxious about it except its two carbs I have to align with some of the adjustments hidden between the carbs and under that awful exhaust pipe. And I don't know if I'm rich or lean, low or high. Rather then cleaning and reassembling that exhaust pipe every time, I guess I will just take the carb off for each try.



Edit:

After playing with it, the low speed screws don't seem to do much. I do a half-full revolution for more gas and it doesn't sound like it changed anything at idle. Doing one carb then the next didn't seem to change anything either (I figured it would have sounded off). I'm supposed to be 1-1/4 turns (which I take as 450 degrees), I currently have them set at 1-1/2 turns.

The highspeed screws look like the difficult ones to reach while on the water, but those are the ones that are needed on the water.... I also don't know why the plastic caps are on them; I think I might just remove them as they limit movement.
I'm thinking of taking the highspeed from 0 & 1/4 to 1/4 & 1/2.

The rpm idle adjustment is still annoying me. I see in a lot of places 1100rpm and a lot of other places 1500rpm. thats a pretty big difference. I'm more worried about the oil adjustment as that is specified to be set at idle.

 

[Triorieel]

Seadoo2: now doesn't do what it was doing in the video with both carbs low speed adjustment set at 1-1/2. (The engine was cold while testing)

I will be taking both seadoo's out into the lake tomorrow to try to get them running.

I still can't find official documentation on what rpm the seadoos should be at idle. Lots of places claim either 1100 or 1500 rpm. I feel 1500 is to high, but what do I know. The bigger problem is the oil adjustment. I know how and have adjusted the oil adjustment to it's idle rpm (seadoo1@1100rpm, seadoo2@1200rpm to reduce rattle), I just don't know what it's idle rpm should be.

I will buy new iridium plugs for seadoo1 before I take it for another water test. Even though the current plugs have less then 5 hours on them, maybe plugs are considered consumable for these things. Hopefully the plugs are the reason for its half power. I don't want to touch it's carb, because I don't know what I am doing and it was running fine before the shorted stator.

Considering all plugs have less then 5 hours on them (plus a winterization), they all look oiled up to me. Maybe this is normal for 2-strokes. Or maybe because I have the oil adjusted to their current rpms and not 1500rpm.

Still looking for insight and I will post my results tomorrow.

 

[dieselndoo]

Ontario, ca or Canada?
Really need to pull the carbs, brother

 

[Triorieel]

Ontario, Canada

I just rebuilt the carb on seadoo2 because it had a flat spot mid throttle, but I have never adjusted a carb before, let alone a dual setup.

 

[mikidymac]

Not sure what all the confusion is....
Low speed screw should be set at 1-1/4 turns out. MAG side high screw at 0, PTO high at 1/4.
Idle set at 1,400 oil pump hash marks lined up.
If it doesn't run correctly at these settings you have dirty carbs, wrong springs or needle and seat issues.
Just run standard BR8ES plugs, the iridium ones will not do anything.
What carb kits did you buy?

 

[Triorieel]

I didn't know the seadoos were supposed to run good with the default settings. I thought it was just to get the thing running to adjust it properly.
As it stands, both seadoos seem to idle fine, I just can't full throttle seadoo2 from idle. and I don't know what seadoo1's new problem is(It ALWAYS has a new problem). These things have been giving me the good idea they need as much work time as play time. I guess at this point, I've put more work into them then have actually gotten joy out of and they still are untrustworthy and not running right.

1400 is a new number for me to add to the list. I have adjusted both seadoos to idle at 1400. Adjusted the oil to the idle of 1400, then adjusted the idle back to 1100 as stated in a few areas including the carb adjustment sticky (which also mentions 1500).

I bought the iridium ones because I'm getting tired of guessing whats wrong. As soon as I put the new ones in, seadoo1 was idling smoother. I don't think plugs should be replaced with 5hrs of use, but thats what this seadoo seems to require so far.

I bought the carb kit online from a dealer in florida.

I spent a whole day testing, cleaning, pop testing that carb on seadoo2. I was only doing this in an attempt to remove that rpm flat spot, which I don't even know if all this work will fix. Spent a few more days replacing the grey fuel lines, cleaning fuel cock, cleaning tank, cleaning hull, fixing fuel sending unit....

I'm still going to go out in the lake and flood the s**t out of them starting with the high speed adjuster and see if they run better...because it's something I haven't tried yet. That highspeed adjuster seems to like to hide on me when the carbs are installed.

Holding choke out a bit seems reduce the effects on seadoo2...but I don't know if thats coincidental at this point or wishful thinking.

 

[Triorieel]

I did the highspeeds adjustment at the dock. I did 180 degree pto and 90 degree mag. Didn't seem to make any difference. To me throttle response time is good, just the overall response...well it dies.

Is my definition of a turn wrong? to me a full turn means 360degrees which means a 1/4 turn is 90 degrees. Or am I doubling it up? google says a full turn is 360 degrees, but maybe seadoo lingo is different?

Since mikidymac is stating it should be running good at default settings and I think my definition of turn is correct. Then at this point I either put the old carb parts back in or order another new set. Where do you guys recommend for a place that ships to canada relatively fast as it already hot and humid here?

 

[mikidymac]

As stated above set it to stock settings. If it doesn't run correctly you have a different carb problem.
The factory setting for idle is 3000 out of the water 1500 rpm in the water. However the 951 is known to run away out of the water if the idle is set too high. Thus my recommendation for 1,400 in the water.