So I am a brand new Seadoo owner as of 3 days ago. So far so good but I could use a little advice on a few things. I bought a 1998 GTI 720 CC from seller on a local internet site. He had all the right paperwork and the story seemed to check out. Skip straight to the questions below if you don't want the story.
It was represented by the seller to have a fresh rebuild with <20 hours ago on the engine with the 1st oversize kit. He advised that it originally failed in conjunction with a worn wear ring which failed to provide enough water to the motor. It came with a service manual with all the rebuild specs and instructions highlighted in yellow. He had not run it in three years and stated he had no time to get it running because he was moving. He also stated be put a new wear ring in and filed the impeller to clean up nicks. He said his machinist buddy helped to set the impeller up. The old ring was in the foot well of the seadoo. I put his battery in it and did a little troubleshooting on site and found that the electrical box was full of rusty water and the bilge was full of very oily water. The start relay was not working due to a three year bath in stagnant water so I shorted across the terminals and it cranked but would not start. The coil had also been bathing 3 years in the electrical box so there was also no spark. The seller returned and told me that the last time he was out it took on a bunch of water and he took it to a local mechanic who resealed the exhaust manifold and advised that he was confident that was the only issue. (Fresh red sealant apparent) He also advised that the mechanic said the automatic bailers should have kept up with it but they were plugged with leaves and junk. I tried a compression test on the cold engine and got 70 and 80 psi without opening the throttle or warming the engine. The price was right and it came with a mint trailer which was worth the asking price so I rolled the dice and I towed it home.
I dried out the coil and cleaned up the terminals and connections in the electrical box. I couldn't get parts in town so I drilled out the rivets on the relay and took it apart and cleaned the contacts and dried and lubricated it and put it back together with #6 nuts and bolts. The fuel in the tank was stabilized ethanol free supreme so I freshened it up with 5 gallons of 50:1 (oil pump delete kit). I hit the button and it fired right up. I killed it to prevent damage and hooked up a hose. I didn't know any better so I accidentally filled it with water before hitting the key and it would not turn over. DOHHH! (newbie mistake. I was too excited to ride and not excited enough about reading manuals!) So I pulled the plugs and blew the water out and tried again. It fired right up and seemed to idle well so I cautiously turned the hose back on just enough for water to escape the "tattle tail" I let it run until the engine warmed up to dry it up the inside. Then I stopped for the night and downloaded an operator manual ( That's where I found the proper flushing sequence).
The next morning I towed it to the lake for a test. It ran but poorly with no top end power and it cavitated on even the slightest wave. After 20 minutes it barely had enough power to get back on the trailer. It felt like a steadily declining fuel delivery problem so I towed it home and checked the spin on filter under the dash. It was clean. I tore the carb and fuel pump down and found a bit of gunk under the diaphram on the pulse side. I also found the little fuel filter in the carb was plugged off with fibrous material and junk. I cleaned everything including the fuel lines and put it back together and put in a new set of BR9ES plugs. I also put a ball valve on the flush adapter and closed it thinking that was probably the source of the cavitation.
That afternoon I took it back to the lake and it ran great from Idle through to full power. It only cavitated on large waves and I'm guessing is performing as it should? 45 mph on wide open throttle. I have probably put about 4 hours on it since then and it seems to run quite well. I also believe I found the source of bilge oil. The grommet was half out of the oil tank pick up which was allowing oil to spill when sloshed inside the tank.
QUESTIONS:
1. Is 45 mph / 65kph about right for this machine or should I expect more?
2. Can I run BR9ES plugs? The manual calls for BR8ES which is only one heat range away. (It didn't run well on the used BR8ES it came with but I haven't tried new)
3. Why do I have to keep oil in the injection tank if I'm running 50:1 mix? (The previous owner said he put in an injection delete kit and it is mandatory?)
4. Is there any other maintenance I should look at other than changing jet oil and greasing PTO and shaft?
5. The warning beeper is dead can I just install an old reverse beeper from my 1998 Skandic skidoo? It looks the same and I have one on hand?
6. How much suction should the bailers have? I can't detect any idling on a hose but maybe it has be fully in the water?
7. Am I correct to plug the flush port when the Seadoo is in use?
Thank you in advance for your advice!
Jeff
It was represented by the seller to have a fresh rebuild with <20 hours ago on the engine with the 1st oversize kit. He advised that it originally failed in conjunction with a worn wear ring which failed to provide enough water to the motor. It came with a service manual with all the rebuild specs and instructions highlighted in yellow. He had not run it in three years and stated he had no time to get it running because he was moving. He also stated be put a new wear ring in and filed the impeller to clean up nicks. He said his machinist buddy helped to set the impeller up. The old ring was in the foot well of the seadoo. I put his battery in it and did a little troubleshooting on site and found that the electrical box was full of rusty water and the bilge was full of very oily water. The start relay was not working due to a three year bath in stagnant water so I shorted across the terminals and it cranked but would not start. The coil had also been bathing 3 years in the electrical box so there was also no spark. The seller returned and told me that the last time he was out it took on a bunch of water and he took it to a local mechanic who resealed the exhaust manifold and advised that he was confident that was the only issue. (Fresh red sealant apparent) He also advised that the mechanic said the automatic bailers should have kept up with it but they were plugged with leaves and junk. I tried a compression test on the cold engine and got 70 and 80 psi without opening the throttle or warming the engine. The price was right and it came with a mint trailer which was worth the asking price so I rolled the dice and I towed it home.
I dried out the coil and cleaned up the terminals and connections in the electrical box. I couldn't get parts in town so I drilled out the rivets on the relay and took it apart and cleaned the contacts and dried and lubricated it and put it back together with #6 nuts and bolts. The fuel in the tank was stabilized ethanol free supreme so I freshened it up with 5 gallons of 50:1 (oil pump delete kit). I hit the button and it fired right up. I killed it to prevent damage and hooked up a hose. I didn't know any better so I accidentally filled it with water before hitting the key and it would not turn over. DOHHH! (newbie mistake. I was too excited to ride and not excited enough about reading manuals!) So I pulled the plugs and blew the water out and tried again. It fired right up and seemed to idle well so I cautiously turned the hose back on just enough for water to escape the "tattle tail" I let it run until the engine warmed up to dry it up the inside. Then I stopped for the night and downloaded an operator manual ( That's where I found the proper flushing sequence).
The next morning I towed it to the lake for a test. It ran but poorly with no top end power and it cavitated on even the slightest wave. After 20 minutes it barely had enough power to get back on the trailer. It felt like a steadily declining fuel delivery problem so I towed it home and checked the spin on filter under the dash. It was clean. I tore the carb and fuel pump down and found a bit of gunk under the diaphram on the pulse side. I also found the little fuel filter in the carb was plugged off with fibrous material and junk. I cleaned everything including the fuel lines and put it back together and put in a new set of BR9ES plugs. I also put a ball valve on the flush adapter and closed it thinking that was probably the source of the cavitation.
That afternoon I took it back to the lake and it ran great from Idle through to full power. It only cavitated on large waves and I'm guessing is performing as it should? 45 mph on wide open throttle. I have probably put about 4 hours on it since then and it seems to run quite well. I also believe I found the source of bilge oil. The grommet was half out of the oil tank pick up which was allowing oil to spill when sloshed inside the tank.
QUESTIONS:
1. Is 45 mph / 65kph about right for this machine or should I expect more?
2. Can I run BR9ES plugs? The manual calls for BR8ES which is only one heat range away. (It didn't run well on the used BR8ES it came with but I haven't tried new)
3. Why do I have to keep oil in the injection tank if I'm running 50:1 mix? (The previous owner said he put in an injection delete kit and it is mandatory?)
4. Is there any other maintenance I should look at other than changing jet oil and greasing PTO and shaft?
5. The warning beeper is dead can I just install an old reverse beeper from my 1998 Skandic skidoo? It looks the same and I have one on hand?
6. How much suction should the bailers have? I can't detect any idling on a hose but maybe it has be fully in the water?
7. Am I correct to plug the flush port when the Seadoo is in use?
Thank you in advance for your advice!
Jeff
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is OK). Rebuild those carbs with ONLY genuine mikuni carb kits (anything else is a waste of time and money). There is a CARB rebuild sticky post on the forum....follow it to the letter for success.
