2007 236 losing prime and overheated cracked hoses

[sstexan]

Hey guys,

So early this spring, I had all the necessary service completed on my 236. I have 320 hours,ZR6 closed cooling, fresh water only, stored in texas always above freezing. I just changed spark plugs, engine belt, impeller, fuel cell filter, and motor oil and filter. I thought that pretty much completed everything that needed to be done.

Well, after 6 or 8 hours this summer, the boat has started to overheat. It started to overheat only at idle and then would cool off once on plane. I knew something was wrong the way the boat sounded. If your boat is making a louder than normal noise, your cooling system is not working (learned that the hard way!) It actually brought memories of my old GT40 sound! Nothing will ever sound that good! After digging through here, everyone said to go look at the strainer for an air leak. The strainer was on tight, but the connections to the schedule 90 pvc fittings were not tight. I tightened those up as well as all the hose connections from the sea water pickup all the way to the impeller.

I went back in to check out the impeller, it was toast, all paddles except one were ripped apart. I changed out the impeller and the boat seems to be running ok.

My question is my hoses seem to have some cracking and I am wondering if this could be my issue as well?

How often should the engine hoses be replaced? What about fuel lines? A crack in a fuel line could get real ugly so I am wondering if I should replace all hoses in the boat? Is this something that should be done at a particular interval?

I am pretty anal about maintenance as I have a very few precious days on the water and don't want to be down due to lack of maintenance. This is first time, the boat left me down since I have owned it. Luckily, I had a spare impeller and fixed it on a trip so we were back the next day! Another reason to always carry a spare impeller and tools!

Thanks,

SSTEXAN

[shag]

You most likely have pieces of the impeller stuck somewhere downstream.... They have to go somewhere. Not real well versed on closed cooling, but should be same basis. Those pieces have to go somewhere...

[sstexan]

yep, I was wondering the same. Do you guys think I should take the exchanger apart and clean? In the manual it says to flush and replace the antifreeze. The antifreeze level is fine, I just wonder if any of the paddles have made there way in the exchanger? Thanks,

[ddipert]

It would be easy enough to check the exchanger. I would be looking for the impeller blades in the cooling system. My theory is at speeds you can pack more water through a clogged passage but at idle there isn't enough pressure. If you can hear an issue then you might have bigger issues. Is the nose there when you first start the boat cold? Or is the noise there just when your srating to overheat?

[thedude]

Might sound silly, but check to make sure your water intake valve is 100% open.

[sstexan]

Thanks for the responses. Yes, the intake is fully open. I still wonder about the water lines being cracked? Has anyone else replaced their water lines? It seems those lines would last 10+ years? My boat is in storage fully covered out of the weather 99.99% of the time.

Thanks

[jasper]

Cracks in the hoses outside of the hose clamps are not too much of a worry, but are a sign. Cracks in the meat of the hose in the operative area is more of a concern. Personally, I would replace any and all cracked hoses, but I'm fairly anal about these things. You'll have to do it in the not too distant future if they are cracked, and no point in waiting for failure. I would not think you would need to do this yet on a 2007, but regardless of the age of the parts, the usage, conditions and the specific hoses (cooling and especially fuel) may require earlier replacement. If you are mechanically inclined even to a small degree, it is not too tough of a job and relatively inexpensive. Go ahead and check your belt while you are at it. I am a big believer in preventative maintenance, so my recommendations are based on my personal method of operating. I replace my impeller every year so I just don't have to worry about it. I don't like the thought of chasing down errant impeller rubber in the cooling system.