Saltaway cause of overheating?

[shwannz]

I think I might have done a fatal mistake. I cam back last night and flushed my engine out with salt away as per instructions. I left the unit hooked up to my engine this morning forgetting to pull it off with the valve set to salt away. The engine hit 250 degrees C and the alarms went off. The boat had no power and we came back to our mooring ASAP. All this happened in the span of 20mins. I have a 5.0 gxi and the 100hour service was done about 20hours ago. I hope someone can offer me some advice.

 

[ENSIGN]

Re: Saltaway cause of overheating?

Remove and inspect the impeller,it's probably tore up from lack of water.

 

[shwannz]

Re: Saltaway cause of overheating?

Remove and inspect the impeller,it's probably tore up from lack of water.

I will have a look tomorrow, but it was smoking when i turned the engine off and smelt like burnt rubber.

 

[QC]

Re: Saltaway cause of overheating?

What was smoking? What year? How soon after the alarm did you shut her off? I am trying to understand how Saltaway contributed. I think you are saying that you left the muffs on?

 

[shwannz]

Re: Saltaway cause of overheating?

What was smoking? What year? How soon after the alarm did you shut her off? I am trying to understand how Saltaway contributed. I think you are saying that you left the muffs on?

Not sure what was smoking, but it was coming from a lower level of the engine (The Monterey has a tight engine bay and I wasn't able to point at it) The Engine is a 2011.
The boat ran idle for about 15 minutes before we set out of the marina (Never went over 1000 rpm) I must have been about 100 meters away from my berth when the alarm went off, we turned right around and moored the boat and turned the engine off. As mentioned earlier, the whole episode happened within 20 minutes.

The mixer unit (URL below) was plugged into the engine flush hose with the valve pointing towards saltaway (without a hose connection, it would have been sucking in pure air) , I am assuming that lack of pressure within the cooling system contributed to the melting of the impeller, that in turn didn't pump sufficient water to the engine.

http://www.charkbait.com/cs/images/boating/salt-away/Copy of MixerL[1].jpg

 

[wire knot]

Re: Saltaway cause of overheating?

Very familiar with flushing issues. I have twice left the flushing hose plug off. It does kill your impeller. The smoking may have been the water pump paint. It will burn.
Mine alarms at 175 degrees, I have never had it go above 200.
First thing to do is pull the water pump apart. Most certainly your impeller vanes are gone. Plan on getting a new impeller. Last time I did this I burnt a shaft seal also. Might plan on replacing that also.
Did you say it had no power?
Keep us posted
Good luck
WK

 

[Black Snow Slide]

Re: Saltaway cause of overheating?

Change out your raw water impeller. It is located on the front of the motor bottom. There are 2 black hoses going to it from the starboard side. Take the boat out of the water. Take the 4 bolts off. ( there are little rubber o rings on the bolts to prevent them from combining out of the housing so you won't loose them in the bilge. ) Take a black sharpy and draw a line across the housing and mounting plate. That line will make it easy to line the two up when reassembling. Slide housing off. Discard rubber propellor and gasket on housing. Coat the raw water perpellor with supplied oil. ( vasoline works as well). Reassemble.

This should take care of you. Make sure you keep a spare and all tools to change it on board. Next time you hear an alarm going off. Stop, toss the anker and investigate. 200 + degrees overheating? You should count your blessings if you didn't do major damage.

 

[shwannz]

Re: Saltaway cause of overheating?

Change out your raw water impeller. It is located on the front of the motor bottom. There are 2 black hoses going to it from the starboard side. Take the boat out of the water. Take the 4 bolts off. ( there are little rubber o rings on the bolts to prevent them from combining out of the housing so you won't loose them in the bilge. ) Take a black sharpy and draw a line across the housing and mounting plate. That line will make it easy to line the two up when reassembling. Slide housing off. Discard rubber propellor and gasket on housing. Coat the raw water perpellor with supplied oil. ( vasoline works as well). Reassemble.

This should take care of you. Make sure you keep a spare and all tools to change it on board. Next time you hear an alarm going off. Stop, toss the anker and investigate. 200 + degrees overheating? You should count your blessings if you didn't do major damage.

Well the impeller has now been replaced and the one that was in the pump looked pretty bad (refer image). The hoses that the sea water pump connects where both dry too (they should apparently have water under pressure). I was crank over the engine once just to get the impeller in a good position and that was followed by connecting a hose to the engine flush hose. (Just in the event there was air trapped in there).

We let the boat run for about 10 minutes or so as we looked for any leaks or signs of water not circulating. Nothing was identified, so we went for a cruise at about 1100rpm out of the marine (15 minute trip) before hitting the open sea which was very flat tonight. I raised it to about 2900rpm keeping an eye on the temp gauge that sat comfortably on 175C. By the time we reached the lagoon, after another 10 minute trip I let the throttle loose and hit top speed for about three minutes or so before turning back and heading home at a little over 1400rpm. The boat showed no signs of overheating and she purred quite nicely. I hope no other damage has taken place, but are there tell tale signs that I can look for before something serious happens?

On this note, I would like to thank you all for your contributions and the especially for the time you have taken to help a real cadet out. I wish I can return the help one day and if not to one of you, then another newbie.

Cheers