Do your homework before buying a used boat

Every used boat should be taken out for a test ride before being purchased, but there are several steps to take before then.

Spring is here. We have celebrated the New Year, we partied for Mardi Gras, and we have attended numerous boat and sports shows over the last few months. The weather is great, and my phone is ringing off the hook with requests for surveys on used boats.

It seems that each year the used-boat market wakes up in the early spring. Maybe it is the nice weather, or perhaps a case of sticker shock at the recent shows. No matter what the reason, if you are shopping for a used boat, there are several things that you can do to help assure that the used boat of your dreams does not become a nightmare.

Not all boats are created equal. There is no such thing as the perfect all-around boat. You should take time to decide exactly what type of boating you will be doing. Will it be fishing, skiing or just cruising? Are you a freshwater or saltwater fisherman?

The more questions you ask the easier it will be for you narrow down the field of used boats to a specific type of rig.

In a perfect world, the person selling a used boat would supply you with a complete list of any and all faults that may exist on his rig, but you and I know that is not going to happen. Sellers tend to suffer from temporary amnesia when it comes to disclosing any problems that may exist with their boat. It is up to you to thoroughly investigate the complete rig before making a purchase.

You can begin by inspecting the cosmetic appearance of the rig. Keep in mind that a boat that has been misused and abused will usually reflect that treatment. If the boat is all scratched up, the color faded, upholstery cracked and mildewed, it is a good bet that there are other hidden mechanical problems to be concerned about.

The motor is the next item to check. Always begin any engine survey with a compression check. When performing a compression test, you are looking for two things. First, what is the compression of each cylinder, and is it close to the recommended reading for that particular engine, and next what is the variation of compression readings from the highest to the lowest reading cylinder? The compression should not vary more than 10 percent from the highest to lowest cylinder. If the variation is greater than that, it could be an indication of a serious internal problem with that lower-reading cylinder. You may want to consult a mechanic before proceeding any further.

If the compression checks good, then investigate the ignition system by checking the spark on each of the cylinders. The best way to check spark is to use a spark gap tester, which allows you to check all cylinders at the same time. With all of the spark plug wires attached to the spark tester, have someone crank the engine with the key switch while you watch each of the spark gaps. You want to verify that all cylinders are firing and that the fire on each cylinder appears to be the same as the others.

The lower unit is probably the most abused component of your prospective new engine. Hitting submerged objects, running aground and shifting the engine at high RPMs can all cause internal damage to the lower unit. Unfortunately, you cannot see inside this aluminum gear housing to inspect for damage. However, you can get a pretty good idea about the condition of the lower unit by inspecting the condition of the lower unit oil. Remove the bottom drain plug from the lower unit and take a small sample of the oil. You are checking to verify that there are no signs of water or metal shavings in the oil. Either of these contaminations would indicate a possible expensive lower unit overhaul is required.

Hook up a garden hose and motor flusher in order to run the engine. Does the engine start easily? Does the engine idle smoothly, and is it responsive when accelerated? Are there any abnormal noises in the engine while it is running?

The boat is the next to be checked. Walk around the boat, feeling for any soft spots on the floor or platforms. Soft spots can be an indication of rotten wood in that area. This can be an expensive repair, and you should consult a fiberglass specialist for an estimate of repairs before purchasing this boat. The boat transom can also fall victim to rot. Tilt the engine up and remove the transom saver from the trailer. Bounce your weight up and down on the lower unit and watch the transom. If the transom flexes in and out, it too could be rotted.

Boat accessories and wiring systems should be thoroughly checked. Turn on navigation lights, bilge pumps, livewell pumps, radios, depth finders and all other accessories to verify that they all work. Any that do not activate should be checked further to verify why they are not working.

Outside the boat, crawl under the trailer and inspect the bottom of the boat. You are checking for any cracks or deep gouges in the hull, as well as the overall condition of the bottom.

While you are on your back, look around at the condition of the trailer. Boats spend approximately 90 percent of their life on the trailer. Check the springs, bunk boards, rollers and axles. Inspect the frame for any cracks or bent cross members. Check the winch, dolly jack and trailer lights.

After you have thoroughly checked the boat, motor and trailer, ask for a test ride. Test rides are not joy rides. This is not the time to take the wife and kids boat riding. You want to spend your time on the water thoroughly testing the boat. Check the ride, acceleration and handling, while monitoring instrumentation and listening for any abnormal noises.

If there is anything that you are not sure of, consult a professional marine mechanic before completing the purchase. Many marine dealerships and shops will perform a survey for purchase. It will cost you a little for the service, but it could be an extremely good investment to get a professional opinion of the rig before you agree to shell out your hard earned money.

If you have any questions about your boat, motor or trailer, you can e-mail me at

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