AQAD40B (165) Hot Water points...

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Medway Mudlark

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Recently fitted calorifier for hot water, have kit but instructions only show for 31,41 series engines which are completely different to mine. Anyone out there know where the take off points are. I am thinking one must be on or near the freshwater circulating pump, and the return to the heat exchanger, as there is a 'bung' on the front. All suggestions appreciated, and any pics even more.

Thanks all in anticipation as I have 'googled' it till the cows come home ( SWMBOS stock suggestion!)
 
Mine were around the cast header tank near the pressure cap. AQD40A.
Looked as though you removed some threaded blanking bolts and merely replaced with brass pipe fitting .
The calorifier pipes were secured with jubilee clips.
If not in rush a couple of RCC members have those 165 hp engines can ask the whereabouts of the feed and return.

http://www.ybw.com/forums/archive/index.php/t-342425.html
 
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One on the inner edge of the header tank, around 6 inches from the top face IIRC.

The other down by the front of the engine near the water pump. Both have the removable screw fittings you'll need!
 
Thanks both.

Have found the one on the face of the header tank which unscrewed amazingly easily! which is more than can be said for the engine anodes. Looking at the diagram, is the flow on actually on the F/W circ. pump? As there appears to be a cover plate which looks removeable (secured by 2 bolts) and a line showing a nipple which presumably substitutes the plate to feed the calorifier
 
Medway Mudlark said:
Thanks both.

Have found the one on the face of the header tank which unscrewed amazingly easily! which is more than can be said for the engine anodes. Looking at the diagram, is the flow on actually on the F/W circ. pump? As there appears to be a cover plate which looks removeable (secured by 2 bolts) and a line showing a nipple which presumably substitutes the plate to feed the calorifier
Click to expand...

I think it's on the engine rather than the pump...the blanking fitting is the same as the tank one...

It's to the port side, close to the drive belts.
 
Thanks,

Will try endoscope with backlight and monitor this weekend, as there is very limited space to front of the engine. The one on the header tank came out very easily, not bad after 30 odd years!
 
They appear to be durable engines! Mine are 2900hrs, 35 years old and use no oil, have no leaks, and apart from a bit of smoke on start up, and full throttle run really well!

The engine mounted plug should be visible from the top, and accessible.

Have a look at an exploded diagram on one of the spare parts sites!?
 
Spoke to Volspec technical yesterday and they seem to think it's on the F/W pump by virtue it has a plug, which can be replaced by a reducer nipple, a nipple, and then a hose clip, all indicative of a hot water take off (on parts list it's the plug on the port side looking forward). And this comes as a parts kit. There are apparently 2 versions of this engine. the early version with square heat exchanger matrix, with square panel on the front, and the later version with a round plate on the front. Mine is the later version.

Still getting my head around this beastie as previous boat had a AQ130/270 set up which I got to know quite intimately after 16 years of ownership. Current boat has been used upper Thames since 2001 and smoked a bit on cold starts, but the more hours its done, the better it's getting, especially now we are down in the tidal part of the Mudway, almost opposite OG. Have to agree though, lovely engine, and very smooth and quiet, and nothing rattles on tick over, can't wait to install the new sound deadening which should arrive next week. Part of the now 3 year refit process. Lots of money spent, but when done will be exactly as we want it, just don't keep a spread sheet!
 
My 40a had around 4K hours when we sold it.Obviously not perfect but cannot remember topping up with oil between services, took a few seconds to start and a trace of smoke on start up. Expence was a recon starter and the starship priced square heater exchanger matrix,which I repaired a couple of times with simple solder job.Managed to track down an unused one on ebay in the end.
Luverly old lumps.
 
Gentlemen, and any ladies

We now have running hot water. For anyone who would like to know I replaced the plug on front of heat exchanger with angled nipple and removed item 14 and replaced with item 27 (nipple) no adaptor was necessary. Ran up engine, after replacing coolant, for about 30 minutes and ….viola,.....very happy SWMBO!

Thanks to all for your feedback and advice.
 
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