Weather contributes to a quiet summer and electrical faults

Published: Thursday, 10 August 2023

OVER the last seven months, River Canal Rescue (RCR) has responded to around 28% fewer callouts than previous years, it tells.

In 2022, the breakdown and emergency assistance firm responded to 130 major incidents (involving submerged, partially sunken or grounded craft, plus salvage work) and 3411 general call-outs, such as electrical, fuel and engine issues, flat batteries, over-heating and gear box failures.

Managing Director, Stephanie Horton, attributes the low numbers to the economic downturn, its impact on finances and the damp weather, which she believes is also behind electrical faults being the top reason for callouts, explaining:

“It’s been an odd year with a quiet summer, despite some peak days,and the weather has not helped.”

In general, RCR receives around 500 calls a month asking for help and advice, so below are tips on how to prevent a part failure and what to do if it does:


Faults are mainly caused by lack of attention to electrical connections. Wires coming away or corroding is a common fault, so visually check and look for loose connections or disconnected wires before you journey, and use a water resistant spray or petroleum jelly to stop damp getting into electrical components like isolators and block connectors.


When the cooling system fails, your engine overheats, and if not identified and remedied quickly, it can cause extensive engine damage.

Overheating is caused by a build-up of air in the marine cooling system which eventually causes the coolant flow to stop.  To prevent this, periodically bleed the air from the system.

If your engine overheats, feel the top and bottom of the water tank; it should be hot at the top and cool at the bottom.  If it isn’t, you have an air lock. To release the air, locate and loosen the bleed screw on your skin tank.
If you don’t have one, or you have a raw water cooled system, run the engine for up to an hour with the expansion tank  cap off to allow the air to escape as it travels though the cooling system.  If you do attempt this, keep topping up the water as the air creeps out, and do not leave the engine unattended.

If you find a leak on your cooling hose, check if the hose needs replacing as it can become hard or disfigured over time.  If the hose is sound, repair the leak and top up the cooling system (bleed as above).

Morse control cables

There’s rarely much warning before this part fails, and when it does it can take you completely by surprise, often resulting in collisions with locks, banks or other vessels. However, there are a few actions you can take to help prevent a failure.

Inspect and ensure the cables are not touching hot surfaces, and are routed so there are no tight bends or kinks.  Oil or grease the cable connections, especially if the controller’s exposed to the weather or left for a period of time.  If the throttle controller becomes stiff or sticking, it may be a sign a cable failure is imminent.

Always carry a spare cable! The gear and throttle cables are interchangeable, so by having one on board you’ll save yourself time and money. Finally change your cables every five years as they don’t last forever.

Battery failure

The most common types of batteries on the inland waterways are lead acid batteries. With these, you need to regularly check their acid levels and top-up with distilled water when required.

To identify if a battery is deteriorating—which means it needs servicing or changing look out for bulging on the battery walls and a white crust on the terminals (this indicates the batteries are gassing). You might also need to frequently charge them.

Always replace the battery bank completely; it’s a false economy to replace one battery at a time, this will only compromise the new battery life.  So replace the starter bank (usually one battery), the domestic bank (typically three or four batteries) and the bow thruster bank (one or two batteries).

When checking batteries, always remove the lid from the battery box to allow any gases to disperse, and ensure they don’t come into contact with any bare wires, metal zips, watches etc as these can cause a spark and if gasses are present, result in an explosion.

To protect against damp and corrosion, spray the terminals and electrical connections with WD40 or a similar product.

Alternator belts

An alternator drive belt (also known as a fan belt) should be checked and replaced regularly.  It has two distinct shapes; a V-belt has small ridge-like teeth and usually drives the starting system, alternator and water pump, a Flat belt is flat with a number of grooves encompassing it and drives the domestic alternator.

To check the belt’s tightness, pinch it between your finger and thumb (approximately half way up the longest point between the pulleys) and push against it. There should be about half an inch of play.  Adjust via the tensioner bracket if there’s too much or too little movement.

To check its condition, while belt removal isn’t necessary, it will make the task easier. If checking in situ, pinch the belt between finger and thumb and twist 90 degrees until you can see the inside wall of the belt. If it’s shiny, cracked or has a groove, it’s ready to replace.

The belt size is usually printed on its top side where you should also find its dimensions. A sequence of numbers such as 10x1025, 10x900, 11.5x1000, 13x1200, 1100A, 950B, 1350C, relate to width and length.  For example 10x1025, 10=width in mm and 1025=length in mm. The letters A, B and C relate to width, A=10mm B=11.5mm C=13mm. Once you’ve been show how, it’s easy to replace a belt.

Engine mounts

Engine mounts are easy to maintain if you know how to look after them. However, they can cause catastrophic damage if they’re adjusted incorrectly or not checked regularly. The engine mount is a rubber shock absorber, and the engine leg, a metal bracket.

It basically comprises a rubber base with a threaded bar through the centre, usually with two or three nuts for adjustment. The engine mount typically bolts to the engine bearer, with the threaded bar extending through a hole into the engine leg.

It’s common to find a single nut under the leg, and either one self-locking nut or two nuts above the leg. The bottom nut is used to set the adjustment height, and the one/two nuts above, lock the mount into place, once the correct adjustment has been set.

Once the mount is fitted, maintenance is easy; check once a month and ensure the bottom nut is tight up against the underside of the leg. If it isn’t, tighten the bottom nut up to the leg. Never touch the top bolt as this will affect the engine alignment.  It’s also worth asking an engineer to take a look in the winter to see if they’re worn or if your engine’s out of alignment.

As always, River Canal Rescue engineers are on hand to help 24/7, for boaters requiring assistance.