Long post warning! Possibly of interest to BC26 owners, otherwise ignore.
As mentioned in the topic below on engine control cables, Alistair and I have decided to change our engines on Iris and Luminos. There are two main reasons for this, firstly because they are now out of warranty, secondly because we want a power tilt, which wasn't available on the Yamaha engine when we bought them, but it is now. However, it turns out it's not quite as simple as we'd hoped. Although we could just do a straight swap for new Yamaha 9.9s it seems that they might not be the best choice, as they don't seem to have had much development in the 6-7 years since we bought them. A number of other engines are now fuel injected instead of carburettor, so in theory more reliable starting (no messing about with chokes, fewer problems with ethanol in the fuel) and better fuel consumption (possibly).
Once we started looking at the engine options we learned that most manufacturers use essentially the same engine for different models, so for Mercury/Tohatsu and Suzuki the 9.9, 15 and 20 are all exactly the same apart from mods to the air intake and the computer mapping, so same size and same weight pretty much. For Yamaha the 9.9 and the 15 are the same. What we then noticed was that the more powerful engines also had bigger alternators, 12A instead of 6A, which is of great interest to those of use with too many toys on board. This made us start to wonder if it might not be a bad idea to put a more powerful engine on the back anyway. Although it won’t make any difference to speed in flat water (we’re not trying to compete with the Coast 250) it should enable us to keep the speed up when things get a bit rough and windy and you want to make some progress into a headwind, albeit at some cost in fuel.
We discussed this with Matt at the boat show in September and he was interested in the idea of re-engining. He was happy that putting a 15 or 20 hp engine on the back wouldn’t be a problem provided it would fit, and provided that those of us with early boats that don’t have the reinforced transoms have them suitably beefed up to take the extra torque loads. We visited a number of engine makers with him to see what was available. First stop was Yamaha who’s smallest efi engine is the new 20hp, but as it’s the same as the 25hp engine it’s a lot heavier than the Mercury or Suzuki engines, 63kg v 54kg, and it’s significantly larger and more expensive. Mercury and Tohatsu stands were more encouraging as their 15 and 20 engines are both efi and also cheaper than the Yamaha. Didn’t visit Suzuki as they won’t give Matt a discount, and missed Honda. Didn’t fancy the Chinese offerings.
One of the main difficulties of choosing a new engine is that the power tilt versions of engines use a much larger mounting bracket than the manual tilts, but the available space on the BC26 is quite tight due to the tapering sides of the cut-out. We can’t afford to order an engine and find that it won’t physically fit on the back of the boat, but getting the key dimensions from the various manufacturers was blood-out-of-stone time. We also found it difficult to find actual engines to measure once we’d left the boat show. I eventually managed to get sufficient info off the interweb to make some life-size prints and take some dimensions off them, then transfer the data into CAD to see how they fit on the transom. It looks like all of the engines need a spacer on top of the transom to lift it up in order not to jam at the bottom, with the Mercury/Tohatsu bracket needing the biggest spacer at 40mm. Question to Andy B if you’re still reading – you’ve got a Mercury power tilt so how is the fit on your transom?
The smallest bracket is on the Suzuki, and it turned out that our local Suzuki dealer in Darthaven Marina had one on the back of a small rib that we could look at, so Alistair and I paid them a visit. We had a good look and measure and compared it to my life-size drawing of our transoms and it all looked very good. Also impressed with the neatness of the control cables which will work with a lot less bending than our current Yamaha cables. James of Darthaven was extremely helpful and knowledgeable, said that they had two engines in stock and we could reserve them at 2022 prices on payment of a deposit, which we duly did. He also persuaded Suzuki to give us the high thrust prop at no extra charge. Darthaven have excellent on-shore facilities and they will either fit the engines on a per-hour labour basis, or they are happy for diy fitting, then they’ll do a post-fitting inspection before letting you go off and wreck it. Warranty is 5 years, 2 years parts and labour then 3 years parts only. You can do diy service for the first 2 years provided you use genuine Suzuki parts, then you have to have Suzuki service it. We’re booked in for fitting in February so I’ll let you know how it goes.
Another question for you Andy B – do you have the same steering linkage on your Mercury engine as we have on our Yamahas? I.e. have you got a cleat on the front of the engine that you pull a line through tight when you drop the engine, and do you have to release it when you raise the engine? Still pondering how this is going to work on our new engines.
...to be continued...
Nick
