Fuel Flow

I have a 1990 75 HP Merc Jet. As soon as I got it I cleaned the gas tank, replaced the fuel line, replaced the OMC filter mount with a Mercury Water Separating Filter, replaced the bulb , replaced the fuel line fitting to the motor and drained the carbs. I would like to add a small disposable filter inline before the Merc filter to catch any particulate matter. Will this reduce the fuel flow?

Re: Fuel Flow

No need to add another filter as the merc one will catch everything. It is a fuel filter as well as a water separator. Hopefully it is installed before the fuel pump.

Re: Fuel Flow

I just like to be completely sure I'm getting clean fuel. When I first got the boat it had an OMC spin-on filter on the transom, before the fuel pump of course since the fuel pump is mounted to the powerhead. On first starting the motor it wasn't able to fully accelerate. Pumping the bulb solved that problem. So I removed the fuel pump and went to the local shop and purchased a diaphragm kit. On taking the pump apart one of the chambers had a fair amount of particulate matter in it. Including aluminum shavings from inside the tank (a homemade aluminum tank) mosquitoes ( for some odd reason Alaska mosquitoes love gasoline) and dirt. It would seem to me that the filter that was on there at the time would also have filtered out the solids. This is why I want to run a two filter system.

Re: Fuel Flow

Something doesn't sound right.
Even the cheapest of cheap filters would have trapped mosquitoes and metal shavings.

Sounds like the motor was run without a filter installed.

Do you have a picture of this "omc filter mount"?

Maybe it is not a filter at all, or has had its filter element removed.

Still one properly installed filter is all you need.

If you have a built in gas tank, water will condense inside and so the merc filter/water separator should be replaced every year.

Even better would be a racor that lets you drain the water out the bottom eliminating the need to replace yearly.

Re: Fuel Flow

I don't have any pics of the old OMC filter. The mount is just about the same as the Mercury filter, in fact the Mercury cartridge may have fit as it also used spin-on filter cartridges. This is what stumps me. That filter should have been sufficient. The fuel line was hooked up to the filter so it hadn't been run without a filter.The tank isn't built in, it sits on a plywood floor that is mounted over the ribs of an aluminum river scow. The boat sat for somewhere between 2 and 3 years before I got it. I suppose I could just try running it with an extra filter. If it does restrict the flow then I will simply remove it and I'm out only about 5 bucks and 10 minutes. The junk in the pump still mystifies me though.
BTW, my new Mercury filter is the one that has a clear bowl and a petcock to drain off any water.

Re: Fuel Flow

Also, I will definitely replace the filter cartridge every spring. I also plan on fogging the engine and emptying the tank and storing it upside down with the cap off. It's a bit of a hassle but well worth it to hit the water with clean, dry fuel.

Re: Fuel Flow

I havent tried one of these but I have heard from many people that these will block many contaminants that a Mercury filter will let by...Yes the merc filter will let stuff pass ...trust me i have been down that road and I'm still working out the kinks....I may get a Racor filter myself
http://www.jamestowndistributors.co...+Gasoline+Spin+On+Fuel+Filter/Water+Separator

Hope this helps.....

Re: Fuel Flow

I havent put one on a boat but have cars, Try a G2 fram gas filter installed in the gas line before it gets to the engine.We also used them on school buses to help prevent fuel contaminated break downs.

Re: Fuel Flow

Thanks for all the input. I do believe I will go ahead and give it a try. Those small inline filters are cheap and they do trap a lot of small particles.

Re: Fuel Flow

Lo and behold, I do believe I've found the very filter I will be trying right here on iboats http://www.iboats.com/Moeller-Clear-View-In-Line-Fuel-Filter/dm/view_id.391050