Running engine in boat yard

I use a hosepipe with simple nozzle fitted so I can adjust the flow of water to match the rate of use by the engine. This goes into the strainer as your initial post suggested. In this way you can start the engine before the water flow, and run the engine for as long as you wish.

That sounds a good plan especially as my strainer and pipework between it and the seawater intake is very generously sized and hence not very bendy for inserting in buckets. BUT what sort of flowrate can I anticipate, the engine is Yanmar 2GM20F.
 
One of those adjustable nozzles for the hose is useful as you can set the water flow to match the engine rpm and have a cuppa while your oil warms up.

I also take the thermostat out before I flush through with a bucketful of antifreeze mix (Volvo 2002 raw cooled).
 
I do exactly as you suggest for a final flush with fresh water, having changed the oil when afloat. With a Vetus strainer a hosepipe with a pistol type nozzle can easily cope with the demands of a Yanmar 3GM.

However, you need to run the engine for at least five minutes before an oil change and I suspect there may be too many opportunities for the pump to run dry if using this method. In this case I put a bucket in the cockpit, constantly topped up with a hosepipe. Then run a length of tubing from the bucket to the pump suction. Tie it to the bucket handle in case it falls out.
 
I use a piece of hose to connect the engine cooling water intake to the galley fresh water. Start the engine, and you get three jobs done at once. Engine warm for oil change, cooling system flushed with fresh and the water tank drained!

Neil
 
??????

You have to have big bucket full of antifreeze mixture because you have to displace all the plain water in the engine and unless the engine is really HOT the thermostat will not be fully openen and most of the flow will simply go through the bypass and out with the exhaust. It will appear there long before all the plain water in the engine is displaced.

Better perhaps to drain the engine once all the salt water is flushed out and then allow it to refill from the bucket of antifreeze.

I suggest that a little is drained out via one of the engine drain cocks and tested for strength when you think the job is done.

Vic
From your reply you seem to assume that the engine is raw water cooled? I must admit I didn't get that impression.
If the engine has a heat exchanger then the position of the engine thermostat is neither here nore there?
The engine (fresh water system c/w anti freeze) is sealed from the raw water side. All I'm saying is that if you want to put a/f into the raw water side then once the engine is running you can add it at anytime.

Maybe I've had a senior moment and got it wrong?

Peter.
 
BUT what sort of flowrate can I anticipate, the engine is Yanmar 2GM20F.

We did this last winter with a 2GM20, raw water cooled, with no problems (twin keels).

Not sure about the exact flow rate but we were surprised, a 2 gallon bucket was empty in no time and a further two galls from the water jar still was not enough to get a warm engine. Next time we will definately have a hosepipe running into the bucket.

Its also surprising how far and wide the spray from the exhaust goes, a peice of heavy fabric / tarpaulin hung over the exhaust outlet helps and will be appreciated by your neighbours !
 
I use a piece of hose to connect the engine cooling water intake to the galley fresh water. Start the engine, and you get three jobs done at once. Engine warm for oil change, cooling system flushed with fresh and the water tank drained!

Neil

Brilliant idea :)
 
Slight variation on this - if you T off the galley (or heads) sink to the engine intake (and close the sink thruhull valve!) you get an easy way to put Antifreeze in the mix without it ever entering your water tank.
 
Similar with the yard I use. Is there any way round this?

Yes - I planned it with the yard so that it was the last one out on the slings for that day, and gave me time to run both the engine and genset through with freash water and antifreeze.

You might wonder what all the others do, who don't flush at the time of lifting. They either don't do anything, or are expecting the engineers to winterise the engine. Perhaps the engineers are allowed by the yard to run the engines????
 
, or are expecting the engineers to winterise the engine. Perhaps the engineers are allowed by the yard to run the engines????



Engineers???:D - that means me !!

seriously - I don't think there would be any difference between the engineers running the engine of a shored up boat and the owner, either way there would be a (very small) risk of the props being vibrated free which the yard could then blame on the owner / engineer.

On a modern cradle I really can't see this happening ever, and normal winter winds are likely to shake things up far more - but I would agree its best to check with the yard first - its probably in the small print somewhere!
 
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Engineers???:D - that means me !!

seriously - I don't think there would be any difference between the engineers running the engine of a shored up boat and the owner, either way there would be a (very small) risk of the props being vibrated free which the yard could then blame on the owner / engineer.

On a modern cradle I really can't see this happening ever, and normal winter winds are likely to shake things up far more - but I would agree its best to check with the yard first - its probably in the small print somewhere!

for instance Hayling Yacht co was adamant I could not run the engine (on pit props) but Wicor, it didn't matter at all. My pit propping was much better in HYC, than Wicor, where we were held up by 2 x 4, instead of chopped telegraph poles.
 
why not take the sea water pump off and then there is no risk of burnning out the impellor as that is the only reason i can see why you have to put water through the system as you wont have it running long enough to damage the rubber exhaust if you only want to warm it up enough to change the oil.
Sorry, to get the oil warm enough you need to run the engine for quite a while, and that "while" is long enough to start carbonizing your v expensive plastic and rubber exhaust components!!
Stu
 
I close off the engines freshwater intake seacock and take off the strainer top.
A hose is then held to pour water into the top of the strainer.
As long as the strainer doesn't empty you should then be keeping up with the needs of the engine.
I do this to warm up my engine before an oil change and to check the water flow coming from my water lubricated sterngland and cutlass bearing.
I do not allow the engine to run in gear more than a few seconds and this would not be appropriate where the engine cooling water does not flow through the sterngland and cutlass bearing.
Some large engines will take a lot longer to warm up the oil and it may be better for the engine to do the oil change afloat so you can 'work' the engine to get it warm enough. On my small 16 HP twin it may only be a few minutes.
 
anyone have an idea of the total capacity of a seawater direct cooled Yanmar 1GM10 for water/antifreeze mix by any chance?

best,

PWR
 
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