Descaling outboard and (raw water cooled) main engines

[singlehanded]

Hi . The bung is at the bottom of the leg near the cavitation plate

 

[singlehanded]

Sir you are correct!! I have found the bung which was out of it's position. As very little water reaches the top of the leg how important is the seal in the clutch?

 

[steve66]

Sir you are correct!! I have found the bung which was out of it's position. As very little water reaches the top of the leg how important is the seal in the clutch?

Very Important, If you get water in it it will seize the main bearing

 

[CAPTAIN FANTASTIC]

I rescale my Volvo raw water cooled engine annualy, using Zero Limescale from Tesco £1.50, it's sulphamic acid. I also use it to descale my outboards.

 

[thinwater]

Does anyone have actual experience of using Sodium Hypochlorite solution for cleaning out the waterways on small outboards (aluminum waterways) and/or raw water cooled mains (cast iron blocks). This method has been "recommended" to me however i am a little dubious of running bleach through the engines to remove the salt deposits.

More to the point, bleach is alkaline and will do nothing to dissolve scale. It will damage the aluminum and certain rubber parts. Test it on a few bits of lime, and them never seek chemistry advise from this person again.

Second, the best acid for aluminum (outboard) and steel/iron/bronze/brass (inboard) are not the same. Rydlime for the inboard, CLR for the outboard.

 

[PowerSlapper]

More to the point, bleach is alkaline and will do nothing to dissolve scale. It will damage the aluminum and certain rubber parts. Test it on a few bits of lime, and them never seek chemistry advise from this person again.

Second, the best acid for aluminum (outboard) and steel/iron/bronze/brass (inboard) are not the same. Rydlime for the inboard, CLR for the outboard.

So what you are saying is it is just another sailing club bar room myth. Thought it might be. BTW. What is "CLR"

 

[pagoda]

So what you are saying is it is just another sailing club bar room myth. Thought it might be. BTW. What is "CLR"

I used a bucket with white vinegar (by the 5 litres) from Ebay. To and from a bucket with a 3gm30. pretty effective if you let it warm up a bit.