Salty deposits in thermostat

[jwatson]

I was advised to change the impeller and stat on my new to me mariner 25 just for peace of mind. I've just taken the stat out And it's pretty manky. What looks to be salty deposits. My concern is that there will be more of these deposits inside the engine. Is there any way I can dissolve these? I've soaked the stat in soapy water and it's working fine. The engine pumps loads of water so I'm not overly concerned about the impeller.

[slate1234]

clean it useing white vinegar, and test in hot water with with a thermometer to check its opening at the correct temp.

[Max...]

It's not too bad (but perhaps best to replace periodically anyway), clean it off as well as the mounting face on the engine and use the old gasket as a template to cut a new one from gasket paper (eBay or local motor factor). Job done.

[jwatson]

Cheers guys. What can be done for the internal canals of the block ?

[Landlockedpirate]

I use Rydlyme, works well and only takes an hour to do. I have made a closed circuit system to run it through the engine.
http://http://www.rydlymemarine.co.uk/

[jwatson]

Fantastic. How does your closed loop system work?

[biffer]

Run it up in a tub and make sure the tell tale goes back in the tub. Closed system.

[jwatson]

I assumed that but thought the volume of water required would dilute the solution too much.

[biffer]

Just leave it running for a while. Doesn't need a load of water as long as it's covering the intake. When I was in the Middle East I've seen them put an outboard in a plastic bag and fill it up with water. Just enough to cover the intake

[Phil M]

I took the lower leg of my mariner 75 and stuffed a short piece of hose over the eater tube (that normally connects to the pump output). I then used a sump pump to run a mixture of malt vinegar and water through the engine, catching all of the water in a big bucket/trug to allow it to re-circulate. It ran for several hours and took a lot of crap out of the engine. The only down side was a severe craving for chips.

If you test the thermostat, do it by putting it in cold water and gently adding hot. I'm told dropping it on very hot water can damage them. New ones are pretty cheap though, so probably worth replacing periodically.

Phil M

[Portholme]

Try everything before you replace. I had a bust one on the opti and assumed it would be a ten quid part. Wrong!! £125 per side!!!!

[jwatson]

Didn't go to bill higham did you?!

[Portholme]

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