Glen E - 2/2/2007 8:50 AM
here is mercury's stance on this:
it is not a prbblem in putting one on if the fuel vacumn that you pull thru the line after the seperator is installed is within spec as per the shop manual.....
it also states that a add'l water sep is recommended if ethanol is present - on page 37 of the Verado owner's manual..
What merc has a problem with, is if it is incorrectly installed and puts drag on the system, if it causes problems with the fuel deelivery, that will void your warranty.
I am glad to see that Merc has modified their stance on this matter. When I talked to them last year they absolutely, positively were trying to talk me out of having a boat mounted filter. Said I did not need it and it could cause me problems.
It is interesting to note that Yamaha's position is that a boat mounted external filter is an absolutely, positively great thing to have. They even market one under their brand name. If you buy their PowerMatched system, an external filter comes as part of the package.
So, since you have a Mercury/Yamaha motor you get to pick and choose whatever you want to do. I vote on having the filter. But, as Yam, Merc and Bombardier all say, make sure that the total fuel system from the tank to the mechanical lift pump inlet is within specs with it comes to restrictions. This should be the case whether or not a boat mounted filter is installed.