Every boat needs on board spares but what do you really need?
It doesn’t matter if you have a 4ft tinny or a 60ft catamaran on board spares are important, you never know when you might need to tap into your spares kit to get you out of trouble or keep your trip going.
But what to stock not only depends on what engines and drives you have it also largely depends on what you are comfortable doing yourself.
Iv’e met a lot of boat owners over the years that have no interest in doing any boat maintenance at all and out source everything to marine business, witch is fine, each to their own but what happens if something does go wrong and you have no phone service or are hours from your nearest service centre?
Long story short this does happen and for those that have no interest in boat maintenance are stuck up the proverbial creek without a paddle. and often because of that one bad experience are nervous every time they go out and worse some sell their boat never to experience the joys of boating life again.
But this doesn’t have to be the case for you.
If you are reading this i am taking an educated guess you are part of the majority of boaties out there that do want to look after their investment by participating in some of their own boat maintenance.
So as i said above what to have on board will depend on your engine / drive set up and what you are comfortable doing yourself, so firstly ill give you a general overview of what the bare minimum should look like in my opinion and then ill expand on that and get into some specifics for different engines and drives.
General spares overview.
OK as an absolute bare minimum i would recommend to stock fluids for everything that has a dipstick and a filler cap so by that i mean engine oil, gearbox oil, drive oil, power steer fluid, coolant, obviously depending on your set up you may require some or all of these.
You will find some components will need special tools to access dipsticks and fillers i wouldn’t worry about these at this stage.
As far as volume for each goes check your owners manuals for how much each engine and drive component requires, sometimes you may find volumes on stickers/plates on each component.
It is up to you if you want to stock enough for the capacity of each component but i would recommend just having enough of each just for top ups.
So lets say you have an engine that takes 40L of engine oil, that’s a lot of oil you would need a very large bilge to keep that amount of oil on hand and to be honest the only time you would normally use the full amount of oil would be at service time anyway, so i would instead keep 5 – 10L on hand just purely for top ups.
So that said you can apply this theory to all the other fluids and make your own judgement on how much of each you would like to have on board.
If you have limited space just carry a small amount to get you out of trouble and if you happen to have a ton of room and are likely to do a full oil change on the fly then by all means stock as much as your engines require.
OK now that we have gone over the general stuff its time to talk about what else should be in your spares kit.
Filters are another good one to have on board, the main filters i like to have are fuel filters.
The only reason i didn’t include these in the general spares is because these will require tools and knowledge on how to replace these.
Boat fuel can get moisture in it quite easily, fuel tanks can develop condensation inside them, fuel filler caps can get water in them in bad weather and marina fuel stops are notorious for having not so great fuel, that’s just naming a few possible causes of bad fuel.
So having spare fuel filters on board makes sense, just be aware that tools like filter removal straps or wrenches may be required for removal and always remember to shut any fuel valves off prior to removal (if you have them)
Also diesel engines will require fuel bleeding after a filter change so make sure you know how to do that before attempting a filter change on a diesel.
It can be handy to have spares of all your other easily accessible filters like oil filters gear box filters etc… but in my opinion these filters could wait for service time.
The likely hood of a oil filter needing replacing is way down the list of likely problems to have at sea.
The next spare for your kit is engine impellers, these again will require tools and knowledge, so make sure you read up or get shown how to do this before you need to change them.
Impellers are one of the most important serviceable items in your engines cooling system they are responsible for sucking up the water from outside your boat and feeding it to your engine.
Impellers are designed to be robust enough to last longer than there service intervals but many factors can reduce there life span like sucking up lots of sand or having a blocked water pickup.
Having an impeller fail will very likely cause an engine overheat situation, so its a good idea to keep these on hand and know how to replace them.
As a general rule of thumb smaller impellers can be prised out with a couple of screwdrivers but larger impellers such as on bigger diesels will need special impeller removal tools and even then can be difficult to remove and replace, so keep this in mind when considering to stock these in your kit.
– Fluids
– Fuel filters
– Impellers
Now that we have spoken about some of the more necessary spares to carry and use, lets dive into what else is handy to have.
I did briefly talk about oil filters (engine oil, trans oil, pwr steer oil, etc…) above and although not what id call essential, if you still have room i would definitely put these in your kit.
If you think of it this way remember the old food pyramid? i would consider fluids as an everyday food, impellers and fuel filters as an every other day food and oil filters as sometimes food.
Wrapping up.
So as you can see when putting together your on board spares there is a lot to consider, its not as easy as saying OK I need this, this and this, you really need to take into account what am I actually going to be able to do myself? do I have the tools needed? do I know how to perform the tasks required? and do I have the room to keep all this stuff on board?
By answering these questions you should have a pretty good idea of whats going to end up in your kit.
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