Re: yamaha 1200 engine failure
What model do you have? GPR, XLT, or XLL? There are some things you must know about those specific hulls. I wrote up a review posted on pwctoday.com:
http://www.pwctoday.com/f14/gpr-xlt-xll-mechanical-issues-tips-112129.html
I'll copy and paste it here for you as well:
There's a few things you should know about an GPR, XLT, or XLL before you purchase one as they have a few issues that need to be addressed.
1) Powervalves- If you own any Yamaha 800cc ski, any XLT, or an 00 to 04 GPR, then you have a powervalve engine. It's not uncommon for these skis to drop a powervalve pin into a cylinder. If this occurs, you'll most likely destroy the engine. The most common and practical precaution is to purchase a set of Waveeater powervalve clips and couplers. Another, more costly, option is to buy gas powervalves.
You can purchase Waveeater powervalve clips and couplers from this link below. Installation directions are also on this site:
http://www.waveeaters.com
2) Pump- These skis cavitate in stock form. Cavitation is when the prop spins without hooking up, similar to the tires spinning out on a car. This can occur from an excess of air in the pump. You need to purchase a pump seal kit from Riva to fill in the stock voids in the pump shoe. Those voids create air pockets in the pump causing the cavitation. You also you need to fill in all the voids around the pump with 3m 4200 quick cure sealant to reduce cavitation. Along with better acceleration, you may even notice a slight increase in top end.
The Pump Seal Kit can be purchased from Riva here:
http://www.rivayamaha.com/RivaStore/... Seal Kits
Directions for installing the pump seal kit and sealing the pump are here:
http://www.cajundude.com/pumpshoe.htm
If you plan on adding an aftermarket prop, this is a great time to do it since your pump will be removed!
3) Catalytic Converters- These skis have catalytic converters in them to lower emissions and they're no good! It's not uncommon for them to fail anywhere from 50 to 100 hours. The 00 to 02 GPRs and XLTs were notorious for this to happen. The 03 and up models weren't as common due to a redesign. When they fail, the catalytic screen will typically break up into pieces and go into the exhaust. RPMs will be reduced at wide open throttle and pieces of your cat will be found in your exhaust. This won't damage your ski when it happens, but 99% of the people who own these skis opt to take the cat out before it fails and put in an R&D D plate and a chip sensor. That'll run you around $90 for both. Putting in a D plate reduces back pressure, decreases the heat, and you may even see a slight increase in bottom end. It will also let you run synthetic oil. With the stock cat in you must run catalytic converter compliant oils.
Due to the decrease in back pressure, you will also need to install a temperature sensor bypass to prevent the warning beep from driving you crazy. *note- this doesn't work on the 05 up GPRs. I'm not sure if they need it or not.
You can purchase the R&D D plate and temperature sensor here:
http://www.rd-performance.com/catalo...TEGORY=Exhaust
Directions for removing the Stinger exhaust can be found at this link below. This will take a while to do the first time. A second set of hands comes in extremely handy due to the size of the exhaust. It's very difficult to pull out of the hull. Once the exhaust is out of the hull, remove the bolts at the front of the stinger and the two bolts underneath it holding it together. Your catalytic converter is between the two pieces. Remember to align the tabs before putting it back together.
http://www.cajundude.com/stingerremoval.htm
4) Hull Inserts- The ride plate, pump shoe, and the rear intake grate bolts screw into hull inserts. BE VERY CAREFUL with these! If you attempt to unscrew one of the bolts they'll often snap the hull insert loose and then you'll have the hull insert freely spinning since they weren't glued properly from the start. From the factory, Yamaha places what looks like a small soda can cylinder on the inside of the hull for the bolts to screw into. To secure these, they just placed a glob of epoxy over them to keep them in place. Since the bolts have loctite on them, the hull insert will often break loose on the inside of the epoxy which causes the entire bolt to just turn with the insert.
To take these bolts out, heat them first with a torch and then use an impact wrench. If you don't have one, just make sure you heat them up good first to loosen the loctite on the bolts. A kitchen torch is plenty of heat for these. Just heat them up for about 45 seconds each and then slowly see if they'll unscrew.
If you do break a hull insert, it's not the end of the world! It's just the end of your weekend plans! For a GPR you'll need to take out everything behind the battery tray to get to the inserts. An XLT or XLL is much easier since there is a lot of room behind the transom wall. You'll notice the globs of epoxy where the bolts should be. Get a mallet and a chisel and get to work! You'll need to get as much of this up as you can. Once the epoxy is removed, then place a set of vice grips over the hull inserts and then unscrew the bolts from underneath. Since you've gone through all this trouble, DO NOT epoxy the stock hull inserts back in! You can purchase an aftermarket bracket that won't require you to do any extra work to remove the bolts in the future. You can epoxy the new brackets to the hull or use JB weld.
You can purchase the brackets here:
http://www.rd-performance.com/catalo...s/Girdle Kit
5) Stock Intake Grate- Whenever you put any aftermarket parts on a GPR, XLT, or XLL you should replace the stock intake grate. Any added top end speed can cause the oem intake grate to be insufficient. What can occur is a high speed, shark, dog leg turn that will throw the rider off at full throttle. This can cause very serious injuries. I recommend an R&D acquavine intake grate to prevent this from happening. It will also improve hook up and handling.
You can purchase an intake grate here:
http://www.rd-performance.com/catalo...Scoop Grates
Here are some handy links for your journeys:
Service manuals for your skis can be found here:
http://greenhulk.net/forums/showthread.php?t=9546
CajunDude's "Do it yourself" instructions for many typical repairs:
http://www.cajundude.com/techpagehome.htm
Atlantic Jet Sports- This is a great company located right here in NJ that usually has everything in stock at great prices.
http://www.atlanticjetsports.com/
Island Racing- Carl is one of the forefathers that developed a lot of the technology and information out there for GPRs and XLTs. He is always more than willing to help you out on the phone and knows a LOT about aftermarket performance parts and the affects to the ski. His prices are also extremely good and his customer support is the best. He comes highly recommended from me. His prop work is also top notch.
http://www.islandracing.net