Tell tales on the motors

Replacing the outboard motors on Seahorse

Given the current petrol price and the rate at which a 90 horsepower two stroke engine burns through fuel, we made the decision to fit smaller, more fuel efficient four stroke engines. You would think this to be an easy task, but, despite the current economic squeeze very few dealers seemed to interested in closing a deal.

The Mercury/Mariner 90 horsepower engines that were fitted to Seahorse when we acquired the boat were 1.4 litre three cylinder engines, and they weigh in at a little under 170 kilograms each. (One of them blew up, in an unfortunate turn of events, but we managed to find a similar pair to replace them.) The also burned around a litre of petrol per minute, per engine, at 25 knots, when the boat is fully loaded with divers. I wanted to replace these heavy, fuel-inefficient engines with smaller, lighter 60 horsepower four strokes to more fully take advantage of how well made our boat is. The truth is that a 6.2 metre rubber duck simply doesn’t need that much horsepower on the back, unless you need to run from the police.

The range of engines that I considered, were Mercury, Honda, Yamaha and Suzuki. Mercury was my first choice as I have owned boats since I was a teenager and I had the most faith in the Mercury engines I have owned. Sadly the price of the Mercury was the highest, Honda the next most expensive, then Yamaha, with Suzuki being the cheapest. I don’t actually think any of them are hugely superior to each other and each has its own good and bad points. There are boats fitted with all four brands of engine that I see regularly, clocking hundreds of hours. I was not too concerned by what I would end up with as since it is such a competitive market, none of them would be bad options. I thought that the best and safest way to be sure I received a detailed quote was to take the boat to each dealer so that they could see exactly what was needed.

The price for removing (not supplying) the old engines and replacing them with new ones varied between R1,800 and a whopping R12,000. The engine prices also varied wildly – some were quoted as really cheap engines but with expensive add-ons such as control boxes, and propellers, and other quotes were all-in. Some engines came with instruments some without, and it gets really cloudy when there is such conflicting information. We were swimming in quotations, none of them comparable to one another as they all included different things. Some quotes were amended several times as the salesmen “forgot” to add certain things. Some of the salesmen were woefully unable to answer questions about their product. The quickest anyone could do the engine swap was three days and the longest was five.

Tell tales on the motors
Tell tales on the motors

So after deliberating, weighing up the positive and negative points of each option, I set out to make a purchase of two 60 horsepower four strokes. This was easier said than done. Suzuki had stock, then they didn’t, and then they did, but when I said I was ready to go ahead, the price went up. Scratch that. Yamaha first had stock and then didn’t, but offered to sell us two 70 horsepower engines – which I didn’t want – if we paid an extra R20,000. The Botswana government had taken all the available stock anyway. Honda were, in all fairness, accurate with a detailed quote but were not interested in the word “discount” and would not budge on price, which I thought was unreasonable given the magnitude of the purchase.

I had now used up all the options I was aware of in Cape Town, so I tried Port Elizabeth, Knysna, Durban and Johannesburg. As old fashioned as it may seem, I wanted to buy from someone who actually had stock of what they were selling.

This rare animal turned out to be a company called Leisure Marine in Johannesburg. With a few emailed questions, a phone call and a bit of discussion, we were ready to place the order on a Monday morning. We made payment, and on Wednesday just before lunch the courier service delivered two 60 horsepower Mercury Bigfoot four stroke EFI engines with all the required bits and pieces for an engine swap to my front door. They weigh under 120 kilograms each and are 1.0 litre four cylinder engines.

I decided to do the engine swap myself, so that there was nothing I didn’t know about how our boat is set up. I had great fun unpacking and fitting the new engines to the boat, after removing the old engines! The effect on the balance and speed of the boat has been fantastic, and follow up service from Leisure Marine has been top notch.

I’ll share more about the process of swapping the motors tomorrow. If you want the potted version with only visuals, you can check out this post, then this one, and finally this one!

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Scuba diver, teacher, gadget man, racing driver, boat skipper, photographer, and collector of stray animals

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