90hp Johnson 1986

[Cappelle]

OK I have a 1986 90hp Johnson. VRO removed. It was running rough last year. The blub would get soft, would take a long time after starting to rev up even with fast idle all the way up and it would take a long time to get to wot speed.. So I'm off season I did a fuel pump kit, fuel line O ring, and both carbs with carb kit. The blub stays hard now. It also starts much better. However it still seem to take longer then it should to get to wot. Examale being if you max the throttle it's takes a while to get the boat planing. At lower speed the motor will some times shake like it's running rough. The other thing Ive noticed is the exhaust smell strongly of gas. It sometimes seems also like it's misting gas out of the exhaust.

Anyway so my question is could it be running really rich? If so what's the best way to check or fix this. Or could this be the fuel tank is not venting properly?

Thanks for any thoughts.

 

[James R]

Sounds like one or more float needles not closing off. Did you replace the needles and seats. You can set the floats a little high to ensure the needles close fully.
Check that all cylinders are firing properly otherwise one or more cylinders will act as a pump and pump fuel through the system. Compression and spark test are very necessary before doing anything else so if you did not do those go back to that and start over.

 

[Cappelle]

Thanks for the reply.
So I don't have a compression tester or spark tester. I can't buy them where I live I'm too far up north (I am ordering them online just need to wait for them to get here.) In the meantime I checked the plugs and 1 was fouled up so cleaned and checked gap. Also moved it to a different cylinder.Started engine on hose and started right up like normal. I tried pulling the plug wires well running and noticed that it made no difference in sound or how it ran when i pulled the cylinder that had the fouled up plug. The others caused it to sputter badly or stall. So this is the problem. So next I traded coils with another cylinder. No change. So coil works. Next I traded the power Pack from the other side of the motor. No change. I also pulled the plug and turned it over to check if i could see a spark at the plug and I can but I don't know if it was enough of a spark.

So i guess my next question is could it be the Stator? I don't know much about this part. From the reading it looks like it charges the battery, runs the Tach and provides power to the power pack. My battery seems to be getting charged (just because i haven't need to charge it in a long time) and the tach doesn't work. It worked some times last year but it would jump around and would never really show the same WOT number twice.This year it's totally dead. Could a stator cause this problem. Maybe Timer base? Or is that piston most likely toast.

Thanks

 

[James R]

A bad tach or bad rectifier can cause ignition problems. Try disconnecting the two yellow wires to the rectifier and the grey wire all at the terminal strip and test the motor again. I dont suspect the Stator. Compression test will show the condition of the pistons and cylinders. Compressions at new are around 120PSI.