Help: Intermittent starting 96 XP

[eastcoasteh]

First off, i'm a total noob when it comes to repair and whatnot...so please excuse that. Any advice you do have is appreciated.

I have a 1996 XP that i use for ripping the kids around on the lake on a tube. It's worked decently,, except the past year or so I've had a hit and miss time starting the thing.
Sometimes it starts right up, sometimes it just seems forever for it to "catch". To the point where I've worn down the battery and had to replace the starter button on it. Also replaced battery and plugs and cleaned the carbs tryign to get this going reliably. My wife and kids are getting tired of the unreliableness of the machine. Funny thing is, when it is running, it runs great!

I've read on here that the original fuel lines can get pretty gummed up and I"m wondering if that's the issue. It does seem like maybe gas just isn't getting to the engine at times, and if/when it finally does, off she goes.

My question being: Does this hypothesis about fuel lines make any sense? Is it worth investing time/money in replacing them? Or should I be looking elsewhere?

Any help/advice is appreciated! THanks

 

[Paul Bretz]

Congratulations on owning one of the most awesome seadoos ever, (Imo). Have you checked the clmpression? The fuel systems on these older 2 strokes always need to be up to par. The carburetors and fuel system is always a good start. Especially if it hasnt been gone through in a while. The fuel lines in question are grey in color and say ‘tempo’ on them. They are not ethanol friendly. If present, replace them. While being in there rebuild the carburetors with only mikuni kits. You can find them from osd marine. Also replace needles and seats with mikuni parts. Check the water seperator underneath the hood and always replace the o ring for it. Imo, just spend the little money and replace seperator. If fuel selector hasnt been replaced, replace it. There is a very informative tutorial on this forum on how to rebuild the carburetors if need be. The oil injection system needs some maintenance if it hasnt been messed with in a while. There is a filter before the oil injector and also the oil lines between injector and rotary valve cover. The lines crack over time and leak causing little or no oil to go to the engine. If you premix, you dont need to worry about the little lines.

 

[AKnarrowback]

When you say "catch" are you refering to the starter turning or the actual motor starting.

If the starter isn't catching take it out, make sure it's an original Denso starter, put new brushes in it as well as a good cleaning and run it.

If the starter is cranking but the motor is not starting then the advice in the previous post is good. Make sure the engine compression is up and within 10psi between cylinders, the fuel system is air tight without grey lines, the carbs are clean and rebuilt with genuine Mikuni parts if needed.

One question. When is the motor hard starting? Under what conditions? Is it on the first start of the day (cold motor) or only when the motor is at running temps. Do you know how many hours are on the motor?

Rotax rotary valve motors can be difficult to start if there is too much clearance of the rotary valve cover. This clearance is caused by wear and water ingestion over time. An example was the 91 or 92 SPs all had a hair too much clearance from the factory, they would start cold but some (100% of the ones I set up) would not start hot. However with the age of your machine it would be prudent to look into all the previous items and consider RV cover wear last. My 94 XP had a slight starting and low end performance problem that only went away with machining my RV cover down .008" to clean things up to spec.

Keep us up to date on what you find.

 

[eastcoasteh]

Hi All, thanks for the feedback....

So I took my machine into the shop before I headed out this year. I told them I wanted all the lines replaced...Anyways, they called me late last week and said "we brought it in and it fired up right away. The boys couldn't find anything wrong and were surprised how well it worked for its age..."

Then since we were hitting a heat wave fro the weekend, and they couldn't get it back in to actually the the lines like I had asked, I took it up to the lake for the weekend...and lo and behold..the same old issue, which basically is:
I hope on, pull the choke and try to start. It starts to turn over, but never "catches". I don't leave the choke on too long as not to flood it. Anyways, what I mean by "never catches" is that it's turning over, there's a bit of water going in and coming out...enough so that it steers ever so slightly as i'm just floating...but it never catches enough to actually go.
If I'm lucky, eventually, it will start to cough and I know i'm close. A few more tries and it'll catch and I'm off. And I may run it for a while, but if I stop for any length of time (ie, more than a few minutes), then i'm back to square one. Once it's running, it works great. Lotsa power still left in this old thing.
If I'm UNlucky, it won't catch at all and I just kill the battery.
In my untrained opinion, it's almost as if it's not getting enough gas to start up..until it sometimes does....i dunno..did I mention i'm not a mechanic? haha

Now, some oddities I noticed which I don't enough about this to correlate:
- The shop says it works perfectly. But they're just running a hose through it, it's not floating in water.
- If I'm next to the machine trying to start it (jsut to see if it'll get close to starting before sitting on it..basically so I don't drift into shore), it does seem to start slightly easier. I weigh about 210lbs and i used to be able to run it with my kid, but we haven't had it start yet this past weekend with both of us on it.
- All the above is to say is I wonder if being in water and maybe submerged slightly is causing any issues...I have a bilge pump and the inside is relatively dry when I'm doing all this work trying to get 'er going.
- The shop didn't have my battery, they used their own. But my battery tested out well and was fully charged when putting on. But I wonder if I don't have a good enough battery for this rig, but I'm quite certain this is NOT a battery issue.

 

[artr]

You did not mention if you tested for spark during the periods of excessive cranking. One of those inline testers that flash would be an easy test to do.

 

[eastcoasteh]

That's a good suggestion. I'm going to grab one this week to test it. When I had this issue last summer, I did replace the plugs, so i'd be surprised if it's that, but that's a good tool to have and a good thing to try.

 

[Ckrawiec]

Hi All, thanks for the feedback....

So I took my machine into the shop before I headed out this year. I told them I wanted all the lines replaced...Anyways, they called me late last week and said "we brought it in and it fired up right away. The boys couldn't find anything wrong and were surprised how well it worked for its age..."

Then since we were hitting a heat wave fro the weekend, and they couldn't get it back in to actually the the lines like I had asked, I took it up to the lake for the weekend...and lo and behold..the same old issue, which basically is:
I hope on, pull the choke and try to start. It starts to turn over, but never "catches". I don't leave the choke on too long as not to flood it. Anyways, what I mean by "never catches" is that it's turning over, there's a bit of water going in and coming out...enough so that it steers ever so slightly as i'm just floating...but it never catches enough to actually go.
If I'm lucky, eventually, it will start to cough and I know i'm close. A few more tries and it'll catch and I'm off. And I may run it for a while, but if I stop for any length of time (ie, more than a few minutes), then i'm back to square one. Once it's running, it works great. Lotsa power still left in this old thing.
If I'm UNlucky, it won't catch at all and I just kill the battery.
In my untrained opinion, it's almost as if it's not getting enough gas to start up..until it sometimes does....i dunno..did I mention i'm not a mechanic? haha

Now, some oddities I noticed which I don't enough about this to correlate:
- The shop says it works perfectly. But they're just running a hose through it, it's not floating in water.
- If I'm next to the machine trying to start it (jsut to see if it'll get close to starting before sitting on it..basically so I don't drift into shore), it does seem to start slightly easier. I weigh about 210lbs and i used to be able to run it with my kid, but we haven't had it start yet this past weekend with both of us on it.
- All the above is to say is I wonder if being in water and maybe submerged slightly is causing any issues...I have a bilge pump and the inside is relatively dry when I'm doing all this work trying to get 'er going.
- The shop didn't have my battery, they used their own. But my battery tested out well and was fully charged when putting on. But I wonder if I don't have a good enough battery for this rig, but I'm quite certain this is NOT a battery issue.

Your ski is 24 years old...it needs a good service. From everything you've told us....it points directly to the carbs IMHO. They need a full rebuild with ONLY GENUINE MIKUNI parts.....AND while your at it: 1) replace all old grey tempo fuel lines with 1/4" black auto fuel hoses, 2) replace the fuel selector valve, 3) replace the fuel/water separator O ring. My '96 behaved pretty much just like yours does UNTIL I did all the things needed...NOW, no problems....starts easily in the water (which is the ONLY true test - running on a trailer on a hose tells you NOTHING, only that it starts - the water resistance load is the true "running" test). Old skis need the love...they still have plenty of life in them if you take care of them and my '96 is my favorite over anything newer that I have.

 

[eastcoasteh]

The issue I have is i'm not overly mechanical and my lone SeaDoo Dealer is not super keen on working on these old rigs....
One question I have: If it is an issue with the carbs and hoses, probably clogging things up....why would that not effect the starting on a trailer? Where does the water resistance part factor in mechanically? Sorry for the noob question, just trying to learn!

From everything I've read and what people have told me on this board, it seems like the Carb clean/rebuild is the way to go along with replacing those hoses. I can only imagine what the filter is like in the carb with those old hoses....I've ordered a Mikuni kit online and hoping to get this done and rolling again.

 

[Ckrawiec]

Hahahahaha....you own a '96 seadoo watercraft......if you ain't mechanically/electrically inclined now....YOU WILL BE SOON.... .

Ok, here is the reality....and I've lived it myself and read it a thousand times......"the ski runs great on the trailer", " it'll rev to the limit and it has great throttle response - on the trailer", etc, etc, etc. BUT once you put it in the water - IF it'll start - it falls flat on its face.

On the water, the drivetrain has to push the impeller through all that resistance.....if the fuel delivery system is NOT up to the task....you got issues. On the trailer, the ski is spinning through the air, fuel delivery can be marginal and still get her started and behaving like it's ready......these older skis will keep you humble, and YES, some dealers won't even touch them any longer......they are finicky, temperamental beasts....but the 2 stroke forum guys and gals still love them and all the headaches they come with.

PS: replace the old hoses AND the fuel selector switch too AND rebuild the carbs (follow the sticky post at the top of the forum). I've always been mechanically inclined but never played inside a carb before my seadoo, it's not rocket science.....take your time, read, look at the pictures, ask for help....you will get there. AND AND AND.....assuming your carb(s) are stock, don't lose the springs.....those are the ONLY parts to re-use unless you get new springs rated at the proper strength for your ski....you are probably at the 80 gram spring (I THINK).

 

[JeremyD615]

On the trailer, with no load on the engine, you’re not using most of the fuel circuits in the carb, so you’d never be able to tell if they were clogged or not working correctly. On the trailer, you’re bouncing off the limiter by the time you get the throttle open, so you’re still not even on the main jet at that point...