Expanding Exhaust Hose and Engine Light/Alarm - HELP

[starks951]

Hey guys..
I was out tooling around the other day with a couple of friends in my 99 X22.  We had no ballast in the boat, and were doing less than 10 mph when all of a sudden the engine light and alarm came on.  I looked quickly at the dash and realized we had an overheat situation.  I killed the engine and popped the engine bubble to get some cooler air around the engine.  When I did this I saw 2 things, 1 was a small amount of wispy smoke (I think it was just some gunk burning off the block since it didn't come back) and 2 was the fact that the exhaust pipe looked like it was expanding.  Some of you are going to say, but how was it expanding since its a semi-solid pipe.  I poked at it and found that it was only the soft outside lining of the pipe that was expanding and not the hard inside shell.

So we let the engine cool for a few minutes then turned it over and took off at a medium clip (figuring the more cold water thru the system the better) then engine temp dropped into normal ranges and ran like normal.

I have seen the engine get hot while low speed cruising in the past and so I am concerned about two things...

1) How would the outside lining of an exhaust pipe expand?
2) Does anyone else have overheat problems at low speed?

Can anyone think of anything else I might look into on this?

Thanks folks..
-K

[masonlk]

Check the impeller in your raw water pump. Follow the directions in the maintenance section.

[ScarabEpic22]

I had this happen to me a few years ago as I was coming home from a friends place on the lake at night.  Wasnt planing yet, just going nice and slow and all of a sudden the alarm went off.  Shut it down immediately when I saw the temp was at 220.  Turned it back on a few mins later and idled back with no problem.  Havent had it happen since, so unless it comes back I wouldnt worry.  But I replaced the impeller that fall anyway as it had never been done in either 5 or 6 years.

[eagle1wi]

Agree with the impeller comments.  I had a friends boat behave this way once - at slower speeds the impeller wasn't pushing enough water to keep the engine cool.  Once the boat got more revs we could tell that the exhaust (and hoses) got suddenly cooler.  The exhaust hose cracked from the inside only and looked fine - we didn't find that out until we took it apart.  Keep an eye on on the hoses after you swap the impeller.

[Rambling Wreck]

Unless the exhaust pipe is over the top expensive, replace it also so the problem is off your mind. At least take it off and inspect it closely. On the other hand, as long as your bilge pump is working, it would be a novel way to clean the entire engine compartment with high pressure hot water!

[eagle1wi]

Unless the exhaust pipe is over the top expensive, replace it also so the problem is off your mind.

ebasic power has corrugated hose for under $20 a foot - so you could replace both sides for under $100
http://www.ebasicpower.com

Before taking all that apart - just do the impeller and re-evaluate.  My opinion is it is the likely culprit and a fairly simple and cheap fix.

If the exhaust hose is giving you problems under pressure - then go the next step.  This stuff is all much much much cheaper than cracking manifolds and potentially overheating that precision aluminum thingy that makes her go vroom.

[azsunn]

I agree with that this is most likely the impeller.  I had the same problem on my old Mastercraft, when I took the impeller out to replace it there were rubber had partially worn so it couldn't get the suction at idle speed.

As far as the exhaust I think it's a good idea to inspect it closely, but the expansion is no doubt caused by the excessive heat of the engine causing the exhaust to be overheated, causing expansion.  Which shouldn't happen again if the engine temperature stays normal after you've replaced the impeller.

Clint

[starks951]

Excellent folks... I will look at Marine Products to see if they have the impeller and possibly the exhaust hose as well, although I don't look forward to replacing the exhaust hose.

Perhaps I will start with the impeller and then keep an eye on the hose.  Should I replace the BELT while I have it off?

Thnx much...

[eagle1wi]

Should I replace the BELT while I have it off?

If you think you need to replace it - yes.  But just having it off is no reason - it is so easy to do even if you are not messing with the water pump.

[masonlk]

Wreck,
 Just leave your engine block drain plugs open when you launch in the spring. It's amazing how clean you can get the bilge with 160* water. It'll get give you a slight panic attack though when you notice the bilge pump is running constantly and the water is steaming!

[Boosted2.0]

when a wire reinforced hose expands like that it can mean that the hose is separating internally - its probably a very good idea to replace it.

I would definitely replace the impeller on the raw water pump and flush the system - check the inlet and hoses and everything for restrictions or debris.

[cyclone]

When your impeller goes bad (yours has cracked or missing fins) it can cook the exhaust hoses. They will eventually collapse internally and the engine will stall and do crazy stuff like blow the hose right off and flood the boat. Definitely replace the impeller and hoses.