Of Revisiting Old Boat Engine Repairs

It has been ages since I've written anything boaty. I know some people like to read about the boat so this essay is about yet more repairs.

It doesn't take much to please me. Mainly I am very happy when plan simply works and even more so when it's a boat engine repair. Over the years I have had repeated issues with fluids leaking into the engine bay. Nearly every part that can be replaced in the cooling and fuel systems has been. If you've seen some of the videos I added in a previous batch of boat essays you may have shared my childish joy that I could take a trip and occasionally not break down. Of course the scariest breakdowns are the ones that happen in the middle of the river. In some places in the Fen the nearest bank could be anywhere between ten and twenty feet away. Without power one just has to wait and see which way the wind wants to blow the boat. Patience and courage are required, as well as luck hoping that there is no other vessel around to be hit by my meandering and uncontrollable fifty feet of solid steel. In most parts of this system overcrowding isn't much of an issue. I do admit to being nervous every time I go through the centre of the nearest town where boats moor on both sides in places. A few years ago I signed up to River Canal Rescue - a breakdown service for the inland waterways. I have not yet had to call them out for a waterside rescue, but it has come close a few times. Most breakdowns recently have been related to issues in the cooling system. Mostly I wait for the engine to cool down and top up the coolant and get on my way within a couple of hours. Every time I have been into the boatyard to service or repair there has been some issue with the cooling system. Repairs have been carried out and all looks fine. The following journey or two may even be without incident, but before too long there is fluid in the tray under the engine. My engine being an old BMC diesel it is, apparently, "a thing" that they leak. Like British motorbikes, they just leak. They're not proud, they're not fussy. If they can take a fluid, it will leak out somewhere ... apparently.

Starting out this boat life as a total novice I've become a little more knowledgeable about where to look when things go wrong. I've certainly become more patient. Some days I have sat with the engine running for hours, while I try to locate the leaks. As part of my most expensive level of membership, RCR undertake a reduced rate on an annual engine service. During the last one, in December, the engineer offered to help me look for leaks. He was either very kind, very bored or he didn't want to go home for some reason. He found two that I'd missed, despite my hours of observation. The Polar end cap (red arrow) was leaking slightly. This was something of a surprise because, adding this cap three or four years ago seemed to solve the overheating problem for a while. It provided a new and extended route through the cooling system. The previous arrangement did not send coolant through the entire length of the heat exchanger because this end was capped off. No wonder I kept overheating. However I have hardly worked the engine hard in the years since it was fitted, so having to replace it was a nuisance. They are not exactly cheap for a bit of rubber.

My engine with the new parts. How clean and dry is my engine tray!

Diesel leaks were also a nightmare. Several years ago The Engineer used to come to visit and seemed to enjoy working on my boat. With his help I ended up replacing most of the fuel pipes and pretty much every nut, bolt, washer and olive in the system. The fuel injection pump was removed and serviced three times by a specialist company - that's a story in itself that I have already told. I bought a complete new spill rail and all sorts of other bits. The CAV housing (green arrow), a sort of spaghetti junction for the fuel system to which the primary fuel filter is attached also needed replacing. Mine was blue like the engine. The Engineer found an old one in his workshop, which he kindly fitted for me. It was definitely not blue, but it could have been used as an aid to navigation on cloudy days. Some years further on it seems it began to disintegrate and sprang a small leak of the slow persistent variety. I could see the drips, but couldn't locate the source. It took the eagle eyes of the RCR mechanic to spot that the CAV housing seemed to have bits missing where they'd broken off. Feeling around and under the edge it was apparent that the leak was coming from that part where the rubber washer was no longer being held securely. 

The old CAV housing with the broken bit clearly visible in front.

Aluminium, copper, brass and steel ... ripe for galvanic erosion?

Having carried out the service, RCR Mechanic left me with a report suggesting that I need to replace the (barely used) Polar end cap and the (bright yellow, previously very obviously used) CAV housing. It took me a few months to get round to doing it, but doing it I have now done. I left it six months because it's been that kind of year. Firstly I don't like opening the hatch to see what I'm doing in the engine room when it's chucking it down. I'm not that keen on the cold either. February saw all my plans for the rest of the year come unravelled as I was stuck in mainland Europe. As you may have read, I eventually managed to get back to the UK and to the boat. Looking for the correct parts is tedious, so I found lots of more interesting things to do. Eventually, though, once some businesses started back, I forced myself to phone and speak to the good folk at ASAP Supplies. As usual they were very helpful even though not all the parts were in stock. £150 later though, they would send me what they had and I would have to wait for the CAV housing until the end of June when their supplies were renewed.

Last month I replaced the Polar end cap. When I took the old one off there was a lot of scale build up and I suppose it was the unevenness of this that forced the existing cap to leak. I cleaned up the heat exchanger and pipes with emery and clamped the new cap into place with the new jubilee clips I added to the shopping list. One month later the level of coolant visible in the heat exchanger is just the same. That hasn't happened before. Yay me!

With three weeks to go before the end of the month I received a notice from ASAP that my order would be completed within two days. Now that's what I call service! Another DHL delivery two days ago and I had no excuse for getting on with the other job. This is the one I wasn't looking forward to, because I knew it wouldn't be as straightforward as the YouTube video suggested. I was, of course, absolutely right. Firstly the maze of copper pipework and the steel throttle cable bracket were attached to the existing housing. None of those were going to be as malleable as the cable itself. Bits had to come off in a particular order to make it possible to remove the next nut or bolt. I managed to do this without spilling any blood (mine is what I was most concerned about) or bestowing curses on any of my tools, the engine, the boat, or indeed anyone with whom she had previously come into contact or their progeny. That is until I reached the final sleeve nut. As I searched in vain for a spanner to fit I began to remember The Engineer's words as he fitted copper and stainless steel fuel pipes back to the bright yellow CAV housing ... "Let's hope you never need to remove this ..."

The hexagonal edges of the nut had become almost smooth and circular. I completed its metamorphosis trying to remove it. Still no cursing though. I thought if I detached the pipe with the housing I could get the whole thing out and the see if the new one was actually going to fit. Fortunately it did, so I loosely assembled everything. Now what to do. Phone a friend. 

I have a friend in the next village who calls himself an engineer, but he is secretly a Mad Inventor. It is almost coincidental that he is also a really nice person and a good friend. He has several projects on the go at all times and holds a number of patents for interesting stuff that has usually served to make someone else money. He would know exactly what to do if he saw my problem. It was convenient for both of us that I head up to his house immediately. Often, if he has come to visit me, he has come by bicycle. I feel ashamed that I have always done the three or four mile journey by boat or van. The CAV housing, even with the attached fuel pipe sticking out, was still small enough to carry in my bike basket. I dragged the bike out of the boat and pumped up the tyres (they always need inflating because I use the bike so rarely). It began raining ... of course it did. Stiff upper lip and all that, carry on. I suppose it must have been close to an hour after we'd spoken on the phone that I turned into his driveway. 

There is always a lot to talk about whenever I see the Mad Inventor - the latest inventions for a start. With the aid of a vice and a special kind of wrench he managed to remove the sleeve nut from the housing and remove the pipe, without damaging it. That was the first impressive act of the afternoon. I thought he would have to rummage through assorted hardware to find exactly the right replacement for the smoothed off nut, but oh no, he had a much better plan. He wondered whether there was enough metal in the head of the nut to file it back into shape, albeit a smaller one. That, dear reader, is precisely what he achieved for his next trick with the aid of the vice, the file, callipers and years of knowing how to make do and mend. The imperial nut now needs a 12mm spanner, but it was perfectly serviceable in its original purpose. Next time I do any work on this part of the boat I shall simply need seven different spanners instead of the present tally of six.

The weather was beautiful today, so I had no excuse not to finish the job. Naturally it was nowhere near as easy as I had hoped but, to be fair, neither was it as difficult as I feared. I had to fit, dismantle and refit some of the parts a few times, because something was always in the way of refitting the next part. It came apart without too much exertion, so I knew it had to go back somehow. Then I had to bleed the fuel system to clear out the air I had introduced. I've actually managed this procedure a few times before and more or less remembered the drill. I was very encouraged to see fuel bleeding through the places I expected and, when the moment came, the engine fired up first time. I am still glowing with pride at having been able to fix something. Normally most repairs I try end in spectacular failure, tears of frustration and another expensive trip to the boatyard. Let's hope I haven't jinxed the repair by crowing about it!