Hose Block Off Question

[crob1]

Please forgive me? I searched and couldn't find the answer for my specific engine (1999 GSX RFI). My question is-which cooling system hose to block off while towing the Sea Doo. I bought a hose pincher set and I think I know which hose, but I want to be sure. Better safe than sorry. I have it on the hose that I think it should go on (for illustration purposes). I'd put in on, down lower, in a towing situation. Is that correct?

 

[GGuillot]

There should be a little arrow where it connects at the head, pointing inward, that's the correct line. Double check by tracing the line from the pump. One will go straight out (out arrow on head) for the hose connection, the opposite one you pinch/block. Pinching anywhere should be fine.

 

[mikidymac]

You should be pinching at the rear of the ski before the hose tee’s off into the black valve with the red adjuster on the muffler.

 

[crob1]

Thanks! I looked for the arrows before I posted. The paint on the head is kind of bubbled or corroded so I can't see the arrows.

 

[JJinSC]

You should be pinching at the rear of the ski before the hose tee’s off into the black valve with the red adjuster on the muffler.

[emoji115]This is important. If not pinched here water can still enter exhaust and then into non-running engine.

 

[crob1]

OK guys, I looked at the cooling system diagram in the manual and found the inlet and outlet hoses. I also think I can see the arrows, so I'm pretty sure I have the right hose. It's pretty tight in the back with the VTS back there, so getting the pincher on the hose way back there would be tricky. Would putting another pincher on the gray hose where I have it now, keep water from entering the engine through the exhaust?

 

[Lhardy]

I may have a stupid question, but why do you need to pinch off waterlines while towing?

 

[mikidymac]

Because water flowing through the pump will be forced into the cooling system. These skis use a wet exhaust so after the water goes through the cylinders and head it is dumped into the exhaust and without the engine running to blow the water out the back the exhaust fills with water then the exhaust manifold then the cylinders and finally the crankcase.

Also the same reason you never have the flushing water on with the engine off.