Day 1

Long day. I left Kelpie at 09.00 and had one of those days. Every lock set against me except St Ives. Two were even worse than that because a bunch of young lads in a day boat kept leaving the slackers (paddles) open. Then I lost my EA key, probably at Houghton lock.Realised when I gotto Hemingford. Fortunately a couple I’d met at Houghton locked through with me and I got to Jones’ in time to buy a new key. Ten quid!

Still, made it so far. Just the New Bedford tomorrow and only one lock at Salters’ Lode. Time for dinner…

Update after dinner: Hot water system fail. Barrel gets hot but when it cools the water contracts and the barrel is squeezed out of shape. Then the lid’s seal fails and it leaks. I thought the pump would allow water to be drawn in but it doesn’t. A centrifugal pump might be better. And a stronger tank. Version 2…

Heat Exchanger under test

Seren has hot(ish) water

It Works!

It’s been a long saga but I’ll abbreviate. Seren has a small diesel engine with what looked like tapping points on the end of the cylinder head for heater hoses, which I hoped to use to provide hot water.

First snag, on the canals, going slowly the engine never really got hot, 40°C max. Going upstream on a river it would make 70°C. So I suspected either a thermostat jammed open, or not fitted at all. ButI couldn’t find a thermostat housing. On most engines it is on top of the cylinder head where the top hose goes to the rad/heat exchanger. No top hose on a Perkins 100 series as modified by Parama for marine use. Turns out it’s in the side of the head where the exhaust manifold/heat exchanger is bolted on, so that has to come off. It’s on studs so has to slide, but can’t slide enough because the starter motor is in the way…

It seemed OK, but I bought a new one anyway, then spent a while poring over the exploded diagram in the manual trying to figure out how it goes back. Eventually I got it right and the engine now runs hotter, as it should.

Calorifiers for boats are like small domestic hot water cylinders but expensive and mostly too big for Seren so I decided to fit a heat exchanger in a plastic barrel instead. It’s food grade plastic, the sort of thing used for bulk shipping of ingredients in the food industry where they are often filled with hot food then sealed to ship. The heat exchanger came from a domestic boiler and is way too big really but it was cheap and on Ebay.

Heat Exchanger under test
Heat Exchanger under test

I rigged up the heat exchanger with some heater hoses and tested it and it got hot. Good start. But the fittings on it weren’t much help for what I had in mind so I cut them off and got a plumber to solder 15mm pipe stubs on. Fitting it to a barrel with curved sides was ‘fun’ and involved several joints and a bit of flexible hose, but it worked.

Heat Exchanger in Barrel
Heat Exchanger in Barrel

The barrel is fitted under the front deck just in front of the engine, hanging for now on parcel strapping. One day I’ll make a proper cradle for it. I’ve wrapped it in insulation but that too needs doing more neatly.

I’ve got a cheapo Ebay electronic temp guage attached to the hot water outlet with gaffer tape and running the engine up for half an hour or so got the gauge upto 33°C, at that point of course the engine thermostat is nowhere near opening. We’ll see what happens on a long run.


Another book finished

My DIY Wiring book has been published. It’s not actually available anywhere yet since the books are in a container somewhere between Thailand and the UK, but advance copies have made it by air, it looks good and more importantly I’ve been paid!

I’ve just finished writing a DIY Plumbing book for the same publisher GMC I did the photos and drawings for that too so it has taken over my life for the last few weeks. Now I’m back to Biofuels International, computers and negotiating some corporate work.