Hi all,
I have a new to me 200hp Yamaha precision blend engine, I don't have the full history on it but I assume it is late 80s model 200AETO. The issue that I have is that 2 of the cylinders are not firing. I have confirmed this buy performing a cylinder drop test and also ran the engine on the house with new plugs - the plugs on the cylinders which are not firing remain new while the others show distinct tan marks consistent with combustion. In order to eliminate the problem I have;
* Compression tested - 105/110 psi all round
* Carb check - confirmed that fuel is entering through the jets on the cylinders that are not firing
* Swapped known good ignition coil and lead between faulty and running cylinder - condition remains the same
What I am unable to ascertain is whether the spark feeding through the coil is strong enough for the non firing cylinders or if there has been any tampering in terms of the connection from the stator coil/CDI to the ignition coil in terms of position, firing order (which is where I think the problem maybe now). Any assistance would be appreciated, it would be awesome if someone has an ignition wiring diagram for this old motor that would help out a lot. I have done a fair amount of searching with little success on this problem.
thanks!
I have a new to me 200hp Yamaha precision blend engine, I don't have the full history on it but I assume it is late 80s model 200AETO. The issue that I have is that 2 of the cylinders are not firing. I have confirmed this buy performing a cylinder drop test and also ran the engine on the house with new plugs - the plugs on the cylinders which are not firing remain new while the others show distinct tan marks consistent with combustion. In order to eliminate the problem I have;
* Compression tested - 105/110 psi all round
* Carb check - confirmed that fuel is entering through the jets on the cylinders that are not firing
* Swapped known good ignition coil and lead between faulty and running cylinder - condition remains the same
What I am unable to ascertain is whether the spark feeding through the coil is strong enough for the non firing cylinders or if there has been any tampering in terms of the connection from the stator coil/CDI to the ignition coil in terms of position, firing order (which is where I think the problem maybe now). Any assistance would be appreciated, it would be awesome if someone has an ignition wiring diagram for this old motor that would help out a lot. I have done a fair amount of searching with little success on this problem.
thanks!
