Do you need to bleed seawater cooling for KAD44 relaunch

Lochlomond

Lochlomond

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www.campbellsairconditioning.co.uk
Stupid question no doubt but hey i'm sure 1 of you clever buggers will keep me right :encouragement:

I relaunch tomorrow having been on hard standing for 4 weeks, this will be a first for me and more importantly with this boat (Got Oct 2015).

My concern is after im in can i just fire up my engines or do i need to bleed the seawater cooling system?

If so how do i do this?

Thanks in advance
 
On my AD41P's i didn't...just launched and fired them up..watched the gauges for a while and all was good.

Can't see how different yours might be?
 
Stats007 said:
No you don't. You should clean the raw water strainers through.
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We had an instance with our KAD32's of the impeller not priming itself and ruining an impeller and setting off the overheat alarm.
Following that, we always used to pour water into the raw water strainer to help prime the system. If you are on legs its not really easy to see if you have raw water circulating properly so IMHO its best to be safe and prime the raw water system. You can use the opportunity to clean the strainers. If you have glass topped strainers you will obviously be able to see whats going on anyway.
 
If your boat has done that once then I'd be inclined to agree - I've yet to have the same issue but it depends on the waterline and what happens when you open the seacock I suppose. The only time mine was out of the water was to have a new impeller as part of a service and winterisation anyway.
 
RIN said:
We had an instance with our KAD32's of the impeller not priming itself and ruining an impeller and setting off the overheat alarm.
Following that, we always used to pour water into the raw water strainer to help prime the system. If you are on legs its not really easy to see if you have raw water circulating properly so IMHO its best to be safe and prime the raw water system. You can use the opportunity to clean the strainers. If you have glass topped strainers you will obviously be able to see whats going on anyway.
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Ditto on KAD42's I also pour water into the strainers to assist with priming. After briefly running the engines I lift the heat exchanger drain hose, loosen the capping bolt, lower to begin pour and check to see that there is indeed water in the heat exchanger. Whether all this is needed or not, I'm not sure, but I do it anyway.
 
I've got KAD 44's. Never need to prime. Always fit a new impellor for the season and remove the old one before the winter to keep as spare.
New impeller is always lubed when fitted so it does not run dry. If they do not prime probabbly a sign the pump is a bit worn.
 
On our previous boat with kad44s I just felt the faceplate on the raw water pump , if running dry it will start to warm up and obviously stone cold with sea water running through . Also on initial start up just rev the engine for a moment to help lift the water up to the pump .
 
Thanks for all the info guys pretty much the answers i was looking for.

She has not been sitting on the hard over the winter, not winterised as i used her every couple of weeks during winter (I know in Scotland mad!! lol) as i only bought her in October so like a kid with a new toy, only been out the water for 4 weeks moving from LochLomond to Rhu giving me time to prep for the sea.

She is on legs, seawater strainers cleaned (Lochlomond been fresh water they were very clean) no issues prior to lifting running and cooling well.

I intended to fill the strainer pots to assist in priming and see that you can touch the pump cover feeling for coldness rather than heat to confirm circulation.

I also saw a vid showing a guy unscrewing the seawater housing cap to assist albeit spurting water everwhere.

Looking forward to my launch tomorrow its to be at least 6 degrees C!!
 
Opening the strainer tops while running will cause a lot of water to go all over your alternator.
But a jug of water in each will aid in priming if the pump faceplates are worn.
Then just check the faceplate when running: should be cold.
 
The impellor housing can leak as well all over the alternator- a common issue on KADs. £500 for a new one or something like £300 exchange the last time I checked.
 
Stats007 said:
The impellor housing can leak as well all over the alternator- a common issue on KADs. £500 for a new one or something like £300 exchange the last time I checked.
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Or if you have time /skills , about £40 for a seal / bearing kit and half an hour on a workshop bench :encouragement:
 
New had KAD 42s in our last boat and advice from engineer was to fire up and check the face plate of the raw water pump. As already mentioned if cold all okay but if a little warm needs a little help. Cracking the filter caps always did the job. No need to have water spray everywhere, as soon as some seeps out tighten it up and all should be good.
 
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