I confess this old merc was cheap as chips and I am very lost with the variations made during the life of the motor. From part numbers I have found that most of lower assembly and transom clamp are all the same for many models. So a frankenstein outboard is probable or it was pinched and chopped many years ago.
Phasemaker? The ignition is what I am working on now. The cdi is red, under the red flywheel and with part number 336-4516. From this part number I can say it is a Phasemaker ignition with isolated coils (green with red covers set at 90 degrees to each other). Currently I need a new pickup coil as one is good and one dead. I was considering rewinding the coil with new wire, but I may be able to get the unit locally (been told there is one 40 miles away for £30). CDI has tested in spec, coils test in spec, compression is good and even enough, and the carb is working but the diaphragm is old and tough. I know carb works, as I have cleaned it and with the sparks out and there is fuel spray ejected when engine is turned over (more fom top cylinder then lower - this is a later on issue if it is still an issue - reed valves would be an engine split).
The gear box has forward and neutral only, so I presume it was put on misaligned. I can see below the carb that the gear shaft crown wheel is toothed across one section and this runs out before reverse is engaged but has ample spare if in forward. The gearbox is stuck on solid to the lower assembly, but I will need to get it off to realign gear selector and replace pump impeller. A past owner has knocked chunks off the fins, I am hoping the heat from a running engine will soften any hard grease acting as glue holding the shaft in, that in combination with a good lagging of penetrating oil - if I can get it in there. Then hang motor upside down and use its own weight to assist it loose, being careful not to let it drop to floor.
As for where it is from, Austraila? Canada?, who knows but it is in Cornwall, England now.. It came with an old boat, then sat in a shed for years and then I got it.
What is the engine doing? Sitting in my shed being a stubborn sod
. The engine will be used on my mates little fishing boat, a 3.3 meter sib (rib style).
