Speedster exhaust 6mm hose melted

[lithium2g]

Hi again,

98 speedster

6mm cooling hose that connects the exhaust to the bit just below the RAVE valve has melted away at some point, not sure if it was last trip out or ages ago, havn't noticed any performance issues. Refer to uploaded picture of schematics outlining part in question.
part # 276000048 is the 6mm hose, for whatever reason it paths underneath the engine to the RAVE valve. Perhaps the engine got too hot i dunno but its not salvageable and i need to replace it. I can get the oem part online from USA but it costs a tonne to ship so I was thinking about using an alternative "cooling hose" but im uncertain of what to get. Im not even sure what travels through the 6mm hose, whether it is cooling water or exhaust air. Im thinking air because there are separate larger hoses that I know have water flush through them. I have run the engine for a few minutes on tap water and im not seeing any water leaks. My wife reckons we should just yolo it on the weekend because we had plans with the boat and she reckons its been broke for ages. Me on the other hand, I want things to work as intended.
Im looking at this as an alternative part:

RSP Vacuum Washer Hose - 6mm, Per Metre 9320791172290 | eBay

And this below is the OEM hose

Seadoo OEM Hose- 6MM Sold by the Meter 296000390 | eBay

This lad pretty much asked the same question 95 GTX Cooling Hose replacement but falls short of identifying a specific part to replace it with.

Thanks

 

[mikidymac]

Yes, you absolutely need that hose as it supplies cooling water to the exhaust pipe. THere is no reason for it to melt. You can replace it with clear vinyl hose from the hardware store but I would also blow all the fittings out with air to make sure they are clean and clear. That should have water flowing through it.

 

[lithium2g]

Yes, you absolutely need that hose as it supplies cooling water to the exhaust pipe. THere is no reason for it to melt. You can replace it with clear vinyl hose from the hardware store but I would also blow all the fittings out with air to make sure they are clean and clear. That should have water flowing through it.

Thanks for the reply mikidymac

I've since studied the 99 model speedster shop manual at length regarding the cooling system and noted where the water is suppose to flow. The 98 speedster shop manual isnt listed for whatever reason but they are the same 787 engine.

I ripped the dodgy 6mm hose off completely and ran the engine on tap water again. A small stream of water does come from the rave valve end of the exhaust but i'd imagine there would be more water coming out with the jet pump sucking it in from the river.

I cant conclusively identify any blocks in the cooling hoses, I can feel cool water going in and warm water coming out of the appropriate hoses as intended.

I am hoping I can get a replacement vinyl hose from the shop today as you have suggested. Will report my results.

This diagram below was extremely useful btw. It says the purpose of this valve/hose is to help with noise reduction and performance improvement.

 

[lithium2g]

Update:

Bought some random 6mm vinal hose and zip ties from hardware store. Connected it all up and it works perfectly. Engine no longer overheating, no water leaking into bilge and performance feels tighter on acceleration. Spent around 8 hours on the water over the weekend Thanks for the wise words.

 

[mikidymac]

You can tell by the color of the pipe that it got really hot at some point.

Glad you are back up and running.