Outboard coooling problems

willtaylor

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7 Aug 2001
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My out board was fine a few weeks ago but now has clogged cooling water passages. I am told there is a proprietary liquid that can deal with this. Has any one used it? With what results?
 
newbie - 1st post hello...

You may laugh - but try coca-cola - its horribly aggressive, and I have used it for unsiezing engines - I suspect it would eat the crud quite nicely.

Or a jetwash hose shoved in the ends....
 
initially try running it in a wheely bin of fresh water.. I always add a bit of washing up liquid.. if nothing else it cleans the bin! In the past when I have had probs when you run it in a bin you may only intially get a small spray from the tell tale but it can shift the crud and usually afer a good "swill" I end up with a good flow...
 
Please tell. What make and model?
How do you know it has clogged cooling passages? Is it because the tell-tale has stopped peeing?
If it's a Mercury/Tohatsu etc clone it could just be the outlet that is blocked. poke it with a bit of wire. It's just a bit of plastic hose that goes up to a union on the cylinder jacket.
The tell-tale is only a by-pass from the main cooling water passages.
If it's a small Johnson it could be a swollen rubber grommet on the water tube to the power head.

It could be your impeller is worn or it could indeed be choked up, but that is your last option really.
 
If totally clogged as in no flow at all then it may be a strip down job and a lot of poking about. The first thing to determine is if the waterways are actually blocked or is it just the tell tale hole that is blocked. If only the tell tale hole a bit of poking with a piece of wire usually clears it.
Provided you have some flow running the OB in a small tank (I use a small rectangular tank of around 3 gallon capacity) with a solution of Fernox© will clean the waterways nicely - use the one which is safe for aluminium boiler systems - I cant remember the type but a google will give you the type you need. I would not run "Coke" through the system as it contains phosphoric acid and even in low concentrations this will play havoc with the aluminium castings.

Alternatively get some radflush (for aluminium engines/heads) and use that in place of the Fernox© but note that radflush will be much more expensive and will need much longer to clear the crud.
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Artificial Intelligence is no match for Natural Stupidity.
 
That link looked quite interesting until I got to the product detail page. The spelling and grammar give me the impression that the company is run by a cartload of chimps.
 
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