Ok, there have been some questions being asked about how to winterize your jet boat. I use the procedure from the Seadoo manual, albeit I slightly modified it, just to make it easier, the procedure is the same.
1. Put fuel stabilizer in your fuel tank on your last ride of the season so you are sure it has made it into the carbs.
2. While on the trailer remove the air box lid and start the engine, bring the engine just off idle a bit and start to spray fogging oil into the flame arrestor moving from side to side. This will ensure you are fogging both cylinders. I like to do it so it starts to choke out the engine but does not stall it out. Then after a bout 15 -20 seconds of that I let loose and spray so much it chokes out the engine. I know you can pop the rubber plug out, for me that is not enough fogging oil. Then I pop the spark plugs out and lather the pistons with fogging oil. Then replace the plugs and ground the spark plug boots and crank the engine over to work the lube over the cylinders.
3. Now for the antifreeze. On my Speedster there are three lines that need to be pinched.
A. the drain line coming from the cylinders low on the exhaust side--usually a clear line that is laying in the bilge, I leave this clamp on all winter.
B.The drain line after the T for the upper flush line. Here is where I modified the procedure. I use a #4 expansion plug available at most Pool supply places.
Like this :
And it put it in the flush line on the back of the boat near the jet pump. If you have twin engines you'll need two of them. I leave these in all winter so the anti-freeze doesn't drain out. I'll get that in the spring.
C. The third and final line. This is the low side of the head but before the T for the Water control valve. This will stop you from filling the exhaust INTERNALLY and draining out of the water box. The main pipe will still fill with anti-freeze where it is supposed to, but not on the inside where the exhaust flows. Right where my finger is where you want to clamp it. I use a Vise-Grip that is for sheetmetal like this:
4. Find you upper flush line insert a funnel(snugly so it seals) and begin to fill the line. This will fill the cooling system with anti-freeze all the way to the point where it will come out the "tell tale" line (bleed hose) that is off the side of the exhaust manifold. This is the HIGHEST point of the cooling system, so you want this open because you are pushing the air out of the system. So it should take roughly a 1/2 gallon of anti-freeze. It is up to you to which anti-freeze to use, I use 50/50 for cars. I don't use R/V anti-freeze but it would probably work the same, just my preference. Also you might need to jiggle the fill line to help burp the air. When you see it come out the tell tale in a nice stream top off the funnel and quickly remove the Vise-Grip this will allow what is in the funnel to go into the Water Control Valve and just drop a bit in the water box.
5. Wash off any spilled Anti-Freeze.
6. Service the Jet Pump(s) and change the oil.
7. Remove battery(s) and store them in a warm environment and on a piece of wood.
8. Do whatever else you do to winterize, like pull your seat cushions etc...
This is more or less just for doing the anti-freeze, also this is the procedure for a 99 Speedster with twin 787's
NOTE: If you use a gallon of Anti-Freeze your clamp might not be tight enough before your water control valve. I originally use the little red clamp(like pictured) but never could get it to fully clamp the line, that is when I switched to the Vise-Grip. I get NO ANTI-FREEZE out of my exhaust at all.
1. Put fuel stabilizer in your fuel tank on your last ride of the season so you are sure it has made it into the carbs.
2. While on the trailer remove the air box lid and start the engine, bring the engine just off idle a bit and start to spray fogging oil into the flame arrestor moving from side to side. This will ensure you are fogging both cylinders. I like to do it so it starts to choke out the engine but does not stall it out. Then after a bout 15 -20 seconds of that I let loose and spray so much it chokes out the engine. I know you can pop the rubber plug out, for me that is not enough fogging oil. Then I pop the spark plugs out and lather the pistons with fogging oil. Then replace the plugs and ground the spark plug boots and crank the engine over to work the lube over the cylinders.
3. Now for the antifreeze. On my Speedster there are three lines that need to be pinched.
A. the drain line coming from the cylinders low on the exhaust side--usually a clear line that is laying in the bilge, I leave this clamp on all winter.
B.The drain line after the T for the upper flush line. Here is where I modified the procedure. I use a #4 expansion plug available at most Pool supply places.
Like this :
And it put it in the flush line on the back of the boat near the jet pump. If you have twin engines you'll need two of them. I leave these in all winter so the anti-freeze doesn't drain out. I'll get that in the spring.
C. The third and final line. This is the low side of the head but before the T for the Water control valve. This will stop you from filling the exhaust INTERNALLY and draining out of the water box. The main pipe will still fill with anti-freeze where it is supposed to, but not on the inside where the exhaust flows. Right where my finger is where you want to clamp it. I use a Vise-Grip that is for sheetmetal like this:
4. Find you upper flush line insert a funnel(snugly so it seals) and begin to fill the line. This will fill the cooling system with anti-freeze all the way to the point where it will come out the "tell tale" line (bleed hose) that is off the side of the exhaust manifold. This is the HIGHEST point of the cooling system, so you want this open because you are pushing the air out of the system. So it should take roughly a 1/2 gallon of anti-freeze. It is up to you to which anti-freeze to use, I use 50/50 for cars. I don't use R/V anti-freeze but it would probably work the same, just my preference. Also you might need to jiggle the fill line to help burp the air. When you see it come out the tell tale in a nice stream top off the funnel and quickly remove the Vise-Grip this will allow what is in the funnel to go into the Water Control Valve and just drop a bit in the water box.
5. Wash off any spilled Anti-Freeze.
6. Service the Jet Pump(s) and change the oil.
7. Remove battery(s) and store them in a warm environment and on a piece of wood.
8. Do whatever else you do to winterize, like pull your seat cushions etc...
This is more or less just for doing the anti-freeze, also this is the procedure for a 99 Speedster with twin 787's
NOTE: If you use a gallon of Anti-Freeze your clamp might not be tight enough before your water control valve. I originally use the little red clamp(like pictured) but never could get it to fully clamp the line, that is when I switched to the Vise-Grip. I get NO ANTI-FREEZE out of my exhaust at all.
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