Muffs

[Andy Moore]

What are they?

[three-rex]

A device consisting of a horse-shoe shaped piece of metal, with a rubber sucker-like device on the end of each arm each looks a bit like a sink-plunger.
The sucker things fit over the water inlets at the lower end of your engine leg, and when connected to a hose-pipe, allow water to be pushed into the cooling system, so that you can run the engine safely on dry land without damage to the impeller.

[ADS]

I thought you had kids

[Andy Moore]

Originally Posted by three-rex

A device consisting of a horse-shoe shaped piece of metal, with a rubber sucker-like device on the end of each arm each looks a bit like a sink-plunger.
The sucker things fit over the water inlets at the lower end of your engine leg, and when connected to a hose-pipe, allow water to be pushed into the cooling system, so that you can run the engine safely on dry land without damage to the impeller.

So if I want to flush my Optimax with fresh water on land, do I need to get a pair? i.e. do I need the engine running to flush it out?

[ADS]

Yes you need to have the engine running to flush it out.

[Andy Moore]

Originally Posted by ADS

Yes you need to have the engine running to flush it out.

Nice one. Thanks. That makes it clearer.

[three-rex]

Originally Posted by Andy Moore

So if I want to flush my Optimax with fresh water on land, do I need to get a pair? i.e. do I need the engine running to flush it out?

I haven't got my opti yet ...
but I believe there might be a flush-plug which screws into the back of the engine, and which will allow you to flush the engine without running - would not flush the impeller through though - others will know better than me!!

[Andy Moore]

Originally Posted by three-rex

I haven't got my opti yet ...
but I believe there might be a flush-plug which screws into the back of the engine, and which will allow you to flush the engine without running - would not flush the impeller through though - others will know better than me!!

You are right. Page 56 of the 135/150/175 manual shows how to attach a hose to the fitting on the bottom cowl. N.B. "engine can be stopped or running at idle speed when flushing the cooling system."

Presumably, if doing this on land the din would be pretty tremendous!

[BogMonster]

My Johnson 6hp aux has a flushing port, basically you take out a screw from underneath (which usefully looks EXACTLY the same as the sump bung, no prizes for guessing how I found THAT out....) and screw in a threaded adaptor. I've made a short flushnwidget to do mine with the engine adaptor on one end, about a foot of garden hose and a standard Hozelock garden fitting on the other. Works a treat, and anyway I can't use muffs on the aux because it has a single bottom inlet for the water, not side ones. It is a lot less messy than the muffs I use on the main engine, which spray water everywhere! A better solution than muffs if available on that engine, IMHO, and a lot easier to use if you happened to want to flush it at a marina rather than with the boat out of the water. As I have to take my boat out of the water every time to fix the tubes anyway, this isn't an issue for me

[Rodan]

you can flush it out on land running using the hose attachment at the rear. don't rev it though as that will knacker the reeds and impellar is not in water. you can flush it out like this not running but the engine needs to be warm or you are only flushing out half the block.

p.s. the noise is great!