Changing Fluids in Your Engine

Changing Fluids in Your Engine: It’s a necessary chore that nobody wants to do, but when you ignore it too long, the consequences are usually very costly.

Many engine manufacturers recommend an oil change every 100 hours for a gasoline engine but every 50 hours for a diesel. If you are a sailor and only run your engine an hour or less every outing, you will need to change the oil even more frequently! Dirty oil inside your engine sitting idle, can destroy the internal surfaces of the engine. A note to those of you in the snow and ice areas where your boat is put away for the winter; it is imperative for the life of your engine to change the oil BEFORE the boat is put away so that your engine sits over the winter with fresh oil. Even if you do not run your boat for the recommended oil change interval during the season, CHANGE THE OIL BEFORE THE BOAT IS PUT AWAY FOR THE WINTER! Running your engine during the boating season creates acid and water accumulation in the oil. Removing this will extend the life of your engine and transmission. Letting it stay in the engine over the winter will shorten the life of the engine dramatically. Preventative maintenance is the key to keeping a well run boat and a happy wallet.

No matter if it’s an inboard or an outboard, a sail boat or a power boat, the basics are the same. Get all your equipment together before you start. To make it easier to remove the old oil, run the engine to bring it to operating temperature before trying to remove the old oil. This gets all the contaminants that have settled to the bottom of your oil pan back into suspension and warm oil is much easier to suck through a plastic or brass tube. Cold oil may not come out no matter how strong your pump is. Change the oil filter EVERY time you change the oil no matter what the manufacturer might say.

Get the tools and equipment that you need for the change BEFORE you start.

1. Lots of oil absorbent pads and rags.
2. Use a self-contained spill proof oil extractor to remove the fluids. You can find them from under $50.00 for the manual pumper suction types, up to a couple of thousand for the built in systems.(This will be the best equipment investment you could possibly make!)We’ve been using a Shur-Flow(I just saw one advertised for around $150.00) for many years without a problem.(just ‘Google’ “manual oil changer”)
3. Screw drivers of the correct size to open plugs or covers.(Too small and you screw up the head of the screw.) go out and buy one of the proper size if you don’t have it in your tool box, and get a decent one, don’t cheap out on a tool that you will need again in a few weeks or months for the same job.
4. Get some plastic bags large enough that you can put around your fuel or oil filter before you remove it to avoid spills.
5. Filter wrench if your oil or fuel filter needs one to remove it(most do).
6. Pliers and wrenches as needed. Be sure you use the proper size wrench so you don’t ruin the nut or plug that you are trying to remove.
7. Buckets of various sizes, plastic containers to hold used filters and oily pads and rags. Cut off gallon milk jugs work well as a temporary holding container while you are working.

Before you start, disable your bilge pump temporarily so that it does not cycle on in case of a spill inside the boat. Place an oil absorbent pad under the engine and a couple more in the bilge to absorb any spills that might happen, and they ALWAYS do! Before you remove your oil filter, place a plastic bag around it to catch the drips that will occur. Do the same for your fuel filter.

Remove the oil from your engine and be sure to put it in a safe, covered container to await proper disposal. Remove your oil filter and put it in a safe container for recycling. Refill the engine with the proper oil after screwing a new oil filter in place. Wipe up any spills and clean the area around your engine, then move on to the next maintenance chore. Be sure and recycle your used oil and filter properly. Most automotive supply stores have a recycle service available.

Lower unit oil needs to be changed regularly as well as transmission fluid in an inboard system. Both outboards and inboard/outboard with outdrives should be changed, in my opinion follow the manufacturer’s recommendation,  but at a minimum of once a year at the end of your boating season if you only go out a few times, and once again during the season. If you use your boat regularly, check the lower unit oil monthly and pull the plug to check the magnet for particles. Smell the oil and look at it. If it smells burned, change it! If it looks milky or runny, get to a mechanic, you have a leak somewhere. While you are checking the lower unit, grease all the pivot points and check the zincs for wear, replace them as necessary. All of this is cheap compared to the bill from the mechanic when something bad happens because you ignored the routine maintenance.

Fuel filter service is as important, maybe more so, as oil filter service. If you have a gasoline engine you will probably get ethanol, whether you want it or not, in your gasoline. This will lead to water in the fuel tank which leads to engine problems and corrosion in the carburetor. It will also tend to clean out your tank and fuel lines if you are just switching over to it. This necessitates your changing your fuel filters very frequently during the first few tanks of ethanol formulated fuel. There’s nothing good about ethanol in your gasoline!

Changing fuel filters can be as easy as unscrewing the hose clamps holding an in-line filter on the fuel line to unscrewing a spin on filter mounted to the engine or a bulkhead. Be sure to use the plastic bags for this job just like you did for the oil, to contain any drips. Of course, secondary filters that you don’t see are going to be another issue. Sometimes they are mounted in a very out-of-the-way place, or they could be internal filters inside the engine. Check your owners manual to find out if you have one and where it might be, or let a professional handle it.

IMPORTANT! Start by thoroughly cleaning the area around the filter and filter housing. Open any hatches and windows for maximum air flow, disable your bilge pump so it doesn’t turn on while you have fuel fumes inside your boat and of course put down your oil absorbent pads under the engine and in the bilge.

You should have a small bucket to put your used filter in and to catch any spillage so it doesn’t get to the bilge. If your filters are small enough, you can cut the top off a 2 liter soda bottle or even a gallon milk jug to catch overflow and to hold your old filters. Empty the bowl of your filter into the bucket and dispose of it properly. Clean the housing and the bowl with a new oil absorbent rag, lubricate the ‘O’ rings and replace the element and bowl. Prime the filter and fuel line as necessary, clean up your mess, dispose of all the rags, filters, etc. properly and you should be ready to go.