Thread: Water ingress into #4 pot??
04-29-2011, 05:16 AM #1
- Join Date
- Apr 2011
Water ingress into #4 pot??
I have an 08 250x and found the #4 spark plug hard to removed, but it did come out ok with out shearing. There is evidence of water ingress as the tip of the plug looked abit rusty. A tap was run through the thread to clean the threads up and plugs refitted with lube on threads OK.
The ski has about 40hrs on the clock and the only running issue I have had is sometimes (1 in 4 starts) after a run and the engine is switch off for a bit (2 -45mins), it can be a little bit hard to start and appears to fire up on 3 cylinders until the throttle is blipped and then all clears and the ski pulls fine. The ski has pretty much always been like this from new and never bothered me to much as it rides fine, so I thought it was just a quirky thing with this model.
After I use the ski I wash/flush on the hose and start the ski the next day off the hose to drive out the water left in the water box.
Any ideas on how the water is getting into the pot? Head gasket?? cracked head?? My dealer has had a look with a scope into the #4 pot and says the piston crown looks a little pitted! But unsure how the water maybe getting in. I undstand that there is a cracking heads issue with these ski's but does that relate to #4 pot? I have put 2 and 2 togeather with the funny starts and water ingress but this may be a red herring and other people have the same funny start issue aswell, but no sign of water ingress
Any thoughts or ideas appreciated??? what are the usual symptoms with a cracked head??
04-29-2011, 08:45 AM #2
the first is the TPS setting,
second the intake manifold defect,
third is the exhaust manifold defect, the most common is the first 2.
Rust on your plug is most of the time cause by condensation,dont ever put oil or grease on plug, you need to put anti seize lubricant otherwize you'll end up with froozen plug.
Check your oil, if it look nice without a creamy aspect(like coffee) you dont have water leak. little pitting on piston,rusted plug all come from condensation coming up from the water sitting in the water box,when you wash/flush your engine you need to lift the front end of the ski and give a few throttle shot to let the water escape from the tank.
It is normal that the days after you'll see water coming out of it, it take at least 3 to 4 start with sitting time in between before it will stop throwing water. That's why you should always fog your engine/SC if it's going sit for more then a day
04-29-2011, 09:01 AM #3
- Join Date
- Apr 2011
Thanks for the reply.
Please can you expand on TPS, what is it and what do you need to check adjust???
What is the manifold defect, casting issue?? I see you can fit a heat absorbing type plate between manifold and head, and suspect this will help heat sink.
What would I need to look for in regards exhaust manifold defect?
Sorry, I meant the threads have been lubed on the plugs not the tips.
The oil gets changed by my dealer every 10-15hrs (3 changes to date) and have not had any bad reports from them, so think my oil must be OK. I guess the condensation issue would make sence on ~4 pot as the ski is store on the trailer with the noise high, so any water droplets would run to the back (pot 4). I will ensure I will start the ski after washing/flushing a couple of mores time over the few days after use to blast out the damp.
04-29-2011, 09:17 AM #4
04-29-2011, 09:54 AM #5
The tps setting have to be done by the dealer,and yes the manifold,it's a casting issue. The heat absorber wont do any good for you. You should check for the water filter stated above.
For the plugs i meant the threads too, there is nothing else then anti seize compound that should be put on the tread,oil or grease will heat and burn and will do no good
Don't forget to fog it if you leave it sit for a few days,foging is your best bet for corosion
For starting issue usually You need to Go by ellimination, start with the TPS and then if it haven't solve the problem you'll need to try the manifold, the manifold casting defect is almost not detectable by eye,so it's a gamble that you need to take.
04-29-2011, 11:23 AM #6
- Join Date
- Jan 2009
I'm curious how can u say the water filter won't work ? Have you tried it before with results one way or the other ? There is a reason this is on every new 300x out there right ? I'm just curious why u say it won't work.
04-29-2011, 11:55 AM #7
04-29-2011, 12:26 PM #8
04-29-2011, 12:40 PM #9
Its interesting that what has been called a 'filter' in the exhaust, and shown in the pictures above, is virtually identical in every way to the catalytic converter that has been in the Yamaha two stroke 66V powervalve engines for years. If I had seen this, with no other input, I would instantly assume it is a catalytic converter, based on looks alone. That honeycomb element in the exhaust WILL get very hot and WILL burn off any unburned fuel/oil/vapor etc, basically functioning as a cat con no matter what it is called ... I imagine it would also help to stop/prevent moisture from coming back up the exhaust and causing the spark plugs to get wet/rust into the head. The Kawi fiche calls it a 'Filter-Comp Muffler', and Riva calls it a catalytic converter.
04-29-2011, 12:58 PM #10
Not only it would, but it DOES help thos problems that you mentioned. And that's the only purpose being there.
It filters water out in a way, so Kawi calls it a filter.
It conversts liquid H2O to steam, so it can be called as a CAT.
Kawi Filter is only $160 MSRP.
Yammi CAT costs $900+ MSRP.
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