Newbie - 1996 XP Battery Question

[Banditsteve]

Hi All from the UK,
Just joined the forum after looking at it for a few weeks and I have learnt so much. I am new to jet skis but have a lifetime of cars and motorcycle experience. I bought a 1996 xp 800 and have had a few problems, most of which I have sorted out by reading this forum (Thanks!). Just a quick question for you - Does anybody know what the battery voltage should be at the battery during cranking? It is 12.5 volts at rest and between 14 and 14.5 when revved so I assume the regulator/rectifier is ok but when I hit the start button, the voltage initially drops to about 9.5 and then settles to 10.5 during cranking when out of the water but obviously there will bo more drain on the battery when cranking in the water so this figure would be even lower then. Is this normal or do I need to put a battery on Santa's list? It turns over ok and starts ok out of the water but a bit of a pig to start in the water and I thought I read somewhere that the computer needs a constant 12 volts? Thanks in advance and I will get a photo sorted out soon when I stop messing about in my garage!! Keep up the good work. Cheers, Steve:cheers:

 

[seadoosnipe]

Normal....

No....sounds like you have a good understanding of what your looking for. The torque on these starter for such high compression engines is why you see the drain. During start up, you've got only drain and no charging system.

But, if you recently bought it and the battery doesn't have one of those stickers that say when it was bought, I'd be thinking of a new battery. They are usually only good for a year or two. Sometimes, you can stretch them into a third year if you have taken good care of it but you pushing it. The MPEM actually uses 5 volts for most of it's operation. There are some ignition system controls in it, so it does have 12 volts also but the drain on the computer systems are usually being referred to the skis with engine managment systems using several sensors to run the motor.....:cheers:

 

[Banditsteve]

Battery...

Thannks for a quick reply Matey. I assume your "No" means its not normal. So what voltage should I expect from a good battery during cranking? Yes you are right about me not having the ski for long. Bought it a couple of months ago and its always been a pig to start most of the time but every now ang again it starts like a champ which leads me to think it is something and nothing which is at fault as if it was something serious it would be a pig all the time. It goes really well when its running and does 60 on the water (Optomistic speedo calibration I think!! Hehe) but it goes well enough. I have replaced both exhaust gaskets which were leaking water, cleaned the fuel filter, removed, stripped and cleaned the carbs and the little filters in there and the fuel pipes are not degrading , (Lots of salt in the carbs from its previous life) set the low speed adjustment screws which were screwed all the way in (Now 1 turn out) replaced a couple of wires which were almost chewed through going into the grey electrical box. The annoying thing is every time I do something it starts beautifully the first time it goes into the water and I think its cured it but then it goes back to normal! Its an emotional rollercoaster!! Hehe. But the important thing is it makes me smile every time I use it(After the cursing dies down) I will stick a battery on it this week and let you know how it does next weekend if I get to the lake. I would be grateful for any other ideas you may have. Thanks again, Keep it sunny side up, Steve

 

[seadoosnipe]

Normal....

Yes, it is normal to see that light on, even with a new battery. It will come on only when starting. After you start, your charging system will kick in and the rectifier send a charge back to the battery and begin to power your system. From that point on, that light should go out.

I said no to the question about needing a new battery, just because that light is on during starting and that in your description, you do seem to understand fully, the functions of the ski.

If the ski is a bit of a pig (not sure what that means), then you might need one. If being a pig means it's starter spin on the engine is less on the water than land, then the torque of the water on the impeller may slow a weak battery down enough to notice. So, kinda uncertain to what you mean by "pig" at this point..........But, I do think you have the jest of what your doing .............:cheers: