Volvo fresh water cooling

[jleaworthy]

I'm thinking of converting my Volv Penta 2002 to indirect cooling. There is a choice of kits - VP's own at about £500 and Martec at about £400. The main difference as far as I can see is that the Volvo has a belt driven pump for the fresh water circulation whereas the Martec's pump is electric. Does anyone have any experience of either of these kits please?

 

[norseman]

Fitted a Martec unit at the beginning of the season to my old Volvo MD11C, and it appears to be fine. The electrical circulating pump used is a Johnson Maag type brushless motor, and I was assured it was very reliable. I chose the Martec unit because of complications with the volvo pump drive, an extra pulley would have to be fitted. The engine has run about 30 hours since the installation, and a higher operating temp. can be acheived which is more efficient. Whatever unit you choose it is important that all waterways in the engine are descaled properly, to get the proper heat exchange and to protect the circulating pump, although you might want to fit a filter on the suction side of the pump.

Norse

 

[olavs]

My MD11D is from 1983 and was equipped with Martec freshwater cooling from its first year. The system is very reliable and this is also valid for the electrical circulation pump. I think my pump is changed twice, which I find acceptable.
If your boat has a saildrive, I would recommend installation of a seawater strainer. Small barnacles that grow inside the saildrive leg get sucked in, pass through the pump and eventually block the heat exhanger.

Olav - Norway

 

[PaulAG]

I also fitted a Martec system to my old MD11C about 4 years ago and have had little or no trouble with it. The electric pump has no objection to driving engine cooling water through a calorifier and/or a car matrix heater for some cabin heating. There is a filter supplied for insertion in the return line to the pump, and at first you will need to clean this quite regularly as the salt water muck is cleaned out of the waterways in the engine. There is also a higher temperature thermostat supplied that allows the engine to run at a higher temperature - definitely noticeable!- and also a different temperature sender to give the right reading on the temperature gauge.
This season though, the electric pump seized and being a mean sort of skipper, took it to pieces to find out why. Basically some damp had eventually penetrated the O-ring seals and rusted the wall of the pump resulting in the semi-circular magnets being pushed out to seize the rotor. A quick sand with wet & dry (dry) and a greasing sorted that out though.

PaulAG

 

[tr7v8]

It's worth pouring some kettle descaler in the block with some very hot water before you fit it. That'll clean out the salty clag and reduce the filter clogging problem.

Jim
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[jleaworthy]

Thanks to all posters for the useful info and very kind tips. Martec is the way I'll go. Cheers

 

[seahorse]

Re: Volvo fresh water coolingDIY!!

I converted my MD2 to fresh water cooling & used domestic radiators to heat the drying locker on my Centaur. A bit time consuming, I made the pump to an article in PBO, cost was about £75.

I've changed the engine to a Kubota & am converting to an electric system - peparing an article for PBO.