Fresh Water Flushing Optimax

brucehawsker · 05 January 2005, 18:54

Due to an attempted theft of my trailer, I was unable to recover Farfetched and she has been in the water in Berthon since 24th December (12 days). She is being lifted by Berthon tomorrow back onto her trailer but the engine will not be flushed by fresh water.

My normal practice has been to flush the engine with fresh water (by running the engine using using muffs) when I recover her - normally after about 7 days in the water or less.

Question 1

Should I flush her with fresh water after every trip even if she is staying in the water in a berth? Of course, I raise the engine at the end of each trip. Or is it OK to do it only when I recover her back to the hard standing?

Question 2

Should I worry that she has not been flushed this time - after 12 days in the water? I could get an engineer from Berthon to do it, but at a cost of £40 - £80. I am not going to be in Lymington for a month possibly....

Question 3

How often do I need to run the engine - and the 6hp 4 stroke auxilliary for that matter? Can I leave the big engine for 6 weeks or more (how long?) with the boat on hard standing without running it? I intend to run the auxilliary once every three months.

Many thanks

Bruce

Turbodiesel · 05 January 2005, 20:12

Ok,..I think in the real world its great to flush your engine after every trip out, but not everyone does. If you can flush it it will just help it go on for that bit longer. But i wouldnt worry to much about it.
Im not sure that you can flush the engine when its in the water, And obviously dont trim it up to put muffs on it while the boat is in the water. (if that makes sence).

I would not worry that its not been flushed after 12 days, just flush it next time you get the chance.

Your Auxilliary, engine if it were me i would check it worked every time i went out, Which is what i do with the boats at work But that maybe me being parranoid. If the Main motor breaks then its good to know the other will start!!.
Leaving the engines for a few weeks is not such a problem. The only thing i would say is, with the Opti dont run the fuel out of it. This will overheat your fuel pump and knacker it (if you do it regularly) Its probably a good idea to get some Fuel Stabilizer and put it in you fuel tank/s This just stops the fuel from deteriating while the engines are not being used. Old Fuel can cause lots of problems.

You can buy proper Flushing attachments for the Optis which will be better than using muffs, Speak to your nearest dealer for advise on how to use it etc.

Hope this helps.

Ian Austin · 05 January 2005, 22:00

Bruce
don't worry about flushing your engine, a couple of times a year is fine. Run for about 15/20 mins at no more than 2000rpm.

You would be far better off running your Aux in fresh water after each use, as the water ways in the smaller engines are very small and are far more likely to block up, just when you realy need it

brucehawsker · 05 January 2005, 22:13

Quote:

Originally Posted by Turbodiesel

And obviously dont trim it up to put muffs on it while the boat is in the water. (if that makes sence).

I understand the point, but why not - is it crazy to run the engine trimmed right up if you have a tap on the jetty?

Quote:

Originally Posted by Turbodiesel

Its probably a good idea to get some Fuel Stabilizer and put it in you fuel tank/s This just stops the fuel from deteriating while the engines are not being used. Old Fuel can cause lots of problems.).

How old is old? After how long does fuel 'go off'

Thanks

Bruce

brucehawsker · 05 January 2005, 22:15

Quote:

Originally Posted by Ian Austin

Bruce
don't worry about flushing your engine, a couple of times a year is fine. Run for about 15/20 mins at no more than 2000rpm.

You would be far better off running your Aux in fresh water after each use, as the water ways in the smaller engines are very small and are far more likely to block up, just when you realy need it

I normally flush it at tickover for about 5 mins - should I really do it for longer at higher revs?

Good point on the aux - I intend to run it on the hardstanding using the muffs

Nasher · 05 January 2005, 22:28

If you're only going to flush an engine a couple of times a year thats used infrequently then perhaps 15/20 mins is a good idea. But if you flush it each time its used before the salt has time to crystalise or corrode anything etc then I think 5 mins should be fine. Remember that no matter how technically advancved it is, all two-strokes like revs, not low speed running.

I always flush it through each time, but I'm like that.

I wouldn't worry about this one time for a couple of weeks, if you are usualy particular about it then the water galleries should be in good shape anyway.

Nasher

Paul F · 05 January 2005, 22:30

when flushing just run engine up till it gets to normal running temp,dont need to rev it up.
Neat petrol held in a tank will last a good couple of months, its when it is mixed with oil that is degrades a lot quicker.
As adviced earlier if worried just add fuel stabiliser.
Paul

brucehawsker · 06 January 2005, 07:08

Quote:

Originally Posted by Paul F

Neat petrol held in a tank will last a good couple of months, its when it is mixed with oil that is degrades a lot quicker.
Paul

I have a 160 litre tank. Put in 115 litres (filled her) five days ago. So assume there will not be a problem if I do not empty her before March / April.

But I have a 22 litre auxilliary plastic tank that I filled 5 October and have not touched since.....

Clearly I should use that as soon as I have the space in my main tank.

Where do I get stabliser? What is it - product name?

Thanks

Bruce

Turbodiesel · 06 January 2005, 07:20

You can smell when the fuel has gone off!, it wont smell like fuel usually does.
The Part number for Quiksilver fuel stabilzer is....

92-802875Q1 For non concentrate which 30ml treats 3.78 litres.(bottle is 355ml)

Or

92-802876Q1 For Concentrate which 30ml treats 22.71 litres (437ml Bottle)

Not sure on the price,speak to your nearest dealer for a price.

Swifty · 06 January 2005, 08:07

When I leave my boat in the marina, I trim the engine up, attach the muffs and hose, trim down then run the engine as normal for about 1 min to flush through, shut down, trim out and remove hose and muffs.

No worries.

pettal · 06 January 2005, 08:15

Hi Bruce,

Petrol these days will last for a good few months before turning as they tend to add a lot of chemicals and preservatives. I have a can of petrol that I use for the chain saw and that's still fine 7 months on!

Although for your opti I would wait this length of time to test it! 3 months is probably your limit.

I flush my engine's twice a year and I've never had any problem, but then none of them have been laid up for more than 3 weeks without use.

Good question about the running engine fully trimmed with muffs on, I'd be very interested to see why this isn't good for the engine!?

swginn · 06 January 2005, 10:30

Quote:

Originally Posted by Pettal

Good question about the running engine fully trimmed with muffs on, I'd be very interested to see why this isn't good for the engine!?

I may be completely wrong but is it something to do with the cooling passages and the possibility of water finding its way back into the cylinder??

Also why bother running the engine when you are flushing it out. I regularly just screw out the plug next to the tell-tale exit and screw in a hose with an attachment I got from my Merc dealer. The pressure from the hose then flushes out the salt in all of the cooling passages. At the end of the day, by flushing out your engine you are simply just cleaning the cooling passages so why would you need to run the engine??

DJL · 06 January 2005, 17:05

Quote:

Originally Posted by swginn

Also why bother running the engine when you are flushing it out. I regularly just screw out the plug next to the tell-tale exit and screw in a hose with an attachment I got from my Merc dealer. The pressure from the hose then flushes out the salt in all of the cooling passages. At the end of the day, by flushing out your engine you are simply just cleaning the cooling passages so why would you need to run the engine??

As far as I’m aware most modern engines have thermostatic values within the cooling system so unless you run the engine its not going to get warm enough for all the cooling passages to be opened. My Mercury manual states that even when the screw in adapter is used the engine should be run - this method has been debated before.

Paul F · 06 January 2005, 17:12

Hence why i said, run engine up to normal operating temp.This will allow thermostats to open..
Paul

Turbodiesel · 06 January 2005, 20:04

If your engine is fully trimmed up (trailer position) i would not run it on muffs all that water that is in the leg has a very good chance of getting back into the powerhead.

Running the engines Trimmed up normally (not trailer postion) is probably ok, but thats just the way I was taught at the Merc Marine factory.

If the boat is in the water im guessing you will have to trim it right up to get the water pickup out of the sea water.

Swifty · 06 January 2005, 22:10

No, put the muffs on then lower the engine down into the water with the hose running. Start up the engine in its normal attitude. Freshwater from the hose goes up and round the engine then out the usuall way into the sea along with all the brine. Salt water doesnt get in because of the seal from the muffs. when you trim the engine up you then pull the muffs off and rinse the leg off.

If I get the boat in at the w/e ill take a picture.

Tim.