Muffs

Andy Moore · 05 December 2006, 11:43

What are they?

three-rex · 05 December 2006, 11:59

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 · 05 December 2006, 12:00

I thought you had kids

Andy Moore · 05 December 2006, 12:06

Quote:

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 · 05 December 2006, 12:30

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

Andy Moore · 05 December 2006, 12:37

Quote:

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 · 05 December 2006, 12:38

Quote:

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 · 05 December 2006, 14:42

Quote:

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 · 05 December 2006, 14:46

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 · 05 December 2006, 14:56

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!

jyasaki · 05 December 2006, 16:21

Might want to check for the procedure in the owners manual before running your motor off the hose attachment.

Most motor manufacturers say that the motor should be off while flushing from the hose attachment (Suzuki being the exception, at least on some of their motors.) I do not know if the thermostats come into play or not (no mention of this in any manual I've seen), but I would think you'd be pretty safe following the manufacturers suggestions (after all, they actually outline how to turn the boat left and right using that marvel of technology, the steering wheel...)

Off the muffs, the motor can be run, but should not be revved up to any degree. If you get an overheat, you should look for a different set of muffs that provides better water flow on your particular motor.

jky

IBWET · 05 December 2006, 17:27

Quote:

Originally Posted by Andy Moore

What are they?

It's something a diver wears when his face when he hits the bottom.

Nos4r2 · 05 December 2006, 20:39

Quote:

Originally Posted by jyasaki

Off the muffs, the motor can be run, but should not be revved up to any degree. If you get an overheat, you should look for a different set of muffs that provides better water flow on your particular motor.

jky

Ditto when using muffs. It's not so much about the set of muffs you're using as the amount of water a normal hose can deliver. The impeller can pump more water than the water mains can supply if the engine is revved-ie don't rev it when using flush muffs.

BogMonster · 05 December 2006, 20:53

Quote:

Originally Posted by Nos4r2

Ditto when using muffs. It's not so much about the set of muffs you're using as the amount of water a normal hose can deliver. The impeller can pump more water than the water mains can supply if the engine is revved-ie don't rev it when using flush muffs.

Oops - have done that a few times. Mind you the mains water pressure at my house is about 12 bar so you get a good flow of water out of the hose!

Cookee · 06 December 2006, 09:09

Quote:

Originally Posted by Rodan

that will knacker the reeds

How does that differ from revving it in the water?

bedajim · 06 December 2006, 09:38

Hi

Don't like the idea of flushing muffs so I always use a water butt

James

Aidan · 06 December 2006, 16:31

cmon guys, there is more to life than Boats and engines.

When Andy was asking about Muffs, he was not talking about engines. Only one of you guys got it right. WHen a diver goes in for it he can get his face broken, its usually due to right hook tho.
As muffs is plural, I can only guess that he means two of them!!!! lucky sod

I will take one of them for you Andy....

jyasaki · 06 December 2006, 17:41

Quote:

Originally Posted by IBWET

It's something a diver wears when his face when he hits the bottom.

Hmmm. Have to look into those. I usually just faceplant, then quickly and sheepishly look around to see if anyone noticed.

jky

Limey Linda · 06 December 2006, 23:33

Quote:

Originally Posted by Aidan

cmon guys, there is more to life than Boats and engines.

When Andy was asking about Muffs, he was not talking about engines. Only one of you guys got it right. WHen a diver goes in for it he can get his face broken, its usually due to right hook tho.
As muffs is plural, I can only guess that he means two of them!!!! lucky sod

I will take one of them for you Andy....

Agood dusting of talc. helps also.

prairie tuber · 07 December 2006, 03:45

Quote:

Originally Posted by Limey Linda

Agood dusting of talc. helps also.

Especially if they're really, really big (you'll be able to see the wet spot).