1998 225 mercury optimax plug foulding

"i have a 1998 225hp merc that

"i have a 1998 225hp merc that fould plugs on cylinder #2 and #4 ,it would not start unless it is trodle up , when start it smokes and if trodle to idle it spit and spatter then cuts out,it also give and intermitten beep ,it will run once in gear ,but will not reach top end speed,i check for spark and compression all same to be good (90psi on all cylinder). could this be injectors ,reeds, or tps."

"The Opti's (and any D

"The Opti's (and any DFI motors for that matter) are extremely hard on plugs. So that's what I would replace first of all.

Your owners manual will call for them to be changed every 100 hours. Most guys that have been running these motors have found that actually every 50 hours is more where the change should occur.

And yes, I know that when you buy plugs for this accross the counter they often go for 15 bucks a piece and you need 6 of them.

But we are talking about a very high-tech motor that retails for about 15K new.

So really, what is 100 bucks worth of plugs once a year on a 15,000 dollar motor?"

the plugs are new

the plugs are new

"In that case then perhaps you

"In that case then perhaps your oil pump is putting out a little too much.

The oil is (injected) into the intake, then through the reeds into the lower crankcase and sucked into the cylinder through the intake port (just the same as a "regular" 2 stroke).

The gas is injected directly into the cylinder once the piston has traveled enough to close off both the intake and exhaust ports.

Because of that, if this is an "oil foul" it will have nothing to do with the injectors - they never handle the oil. And which is also why you can never simply bypass the oil pump and mix the gas and oil on a DFI motor.

The oil pump can be checked with a DDT at a dealer to see if it's operating within spec. Unfortunately, there is no "ohm meter in your garage test" to check out many of the components on the Opti - that's the price of technology..."