Got up at 5.00am to launch out of Cruden Bay. Picked up my brother on route and we were on the water by 7.30am. The sea was calm which is a first for the east coast!
I have an issue with the main engine. I had a oil recirculation pipe blow off in April (first trip out in April). Thinking it was carb related I'd striped them the previous week. The engine is a 2006 Tohatsu 60hp, 2-stroke. The carbs were clean as a whistle, no deposits, etc. Fuel was fresh. It's an autolube engine (Quicksilver topped up).
I also renewed the primer bulb after that first outing with a Quicksilver replacement, as the original rubber bulb was hard.
Not far out of the harbour after launching - the engine felt bogged down. Normally the Tohatsu is eager and quick to respond, but it was very sluggish. I'd reset the fuel pilot screws on the carbs to 1 5/8 turns from lightly seated, but it was struggling. After various impromptu stops it ended up at a full 4 1/2 turns out, which is crazy.
The engine pumps water fine. The impeller was changed last season. I also renewed the fuel pump diaphragm, thermostat, last year, etc. All genuine Tohatsu parts, etc. The head gasket spark plug holes had threaded at the start of the season, so I had them retapped (steel inserts) and used a new gasket. No indication that the gasket has failed.
The spark plugs are from last year. I changed them to another set I had on board and it did seem to make a difference. I'll try changing the sparks, but wondered if anyone has any other suggestions. Can the timing go off, or could this be a weak spark from one of the HT leads?
With two-up we topped out at 27mph which is poor. It normally does well over 30mph and the power delivery is instant and smooth.
Earlier thread here for info: Tohatsu running rough