Cruisers & Sailing Forums (
-   Engines and Propulsion Systems (
-   -   How Do I Plumb a Water Heater to a Westerbeke 40 / Perkins 4.108 ? (

svaletheia 07-04-2010 06:27

How Do I Plumb a Water Heater to a Westerbeke 40 / Perkins 4.108 ?

I have a Westerbeke 40 (very similar to a 4.108 Perkins) - to which I wish to add a hot water heater. The manual says to take the hot water from the thermostat output but the size of the hose here is something huge like 1-1/4" ID and I have no idea how to ensure the right amount of cooling water flow for the engine while connecting this huge hose to the hot water connections on a typical heater (I'm considering isoTemp).

If anyone has any experience, insight, or suggestions I would sincerely appreciate it.

Sailabel 07-04-2010 07:11

We went through the same thing in hooking up coolant lines from our Yanmar. The first thing I did was to call the Yanmar dealer to find out how much 3/4" hose we could use (how far the water heater could be from the engine). Armed with that info, we ran a new 1.25" hose from the thermostat housing down to a valve and tee (so we could create a restriction sending coolant to the water heater, with some coolant bypassing the water heater), a tee below the valve for the coolant returning from the water heater) and then a section of 1.25" hose heading back to the engine. Works fine for us.

All this was necessary because our engine does not have a provision for connecting a water heater... unlike many of the newer engines.


donradcliffe 09-04-2010 19:32

see the discussion on

S Y Tuppenny 17-12-2011 18:14

Re: How Do I Plumb a Water Heater to a Westerbeke 40 / Perkins 4.108 ?

We have an Allied Wright ketch with a Westerbeke 40 (4108). We have had endless problems with our hot water system and wondered if you managed to get yours set up?

Ruth Cawston
Gillie Davies

All times are GMT -7. The time now is 00:08.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.