Fuel problems - A happy story

[Concord]

Our boat has a plastic fuel tank installed about 6 years ago and the fuel was mostly new last season.

After cleaning out the small in line filter several times this season we decided to upgrade and install a Racor with a water separator. The project went fairly smooth and we removed the Carb (2x) in the process. The first time we found a fair amount of debris in the main jet hole so we cleaned it out and reassembled the carb. The engine would run then die. The second time we found what appeared to be varnish in the needle/float assembly.

Prior to re-installing the carb the second time we used the manual pump to flush the fuel system. The first pint of fuel looked pretty bad - lots of debris from fine black powder to flakes up to 3/16" and the bottle had about 20% water (black) that separated and the fuel on top was pretty cloudy. We decided to keep pumping until we liked what we saw. By the fourth pint there was no separation and the fuel was still a little cloudy but looked much better. There was still a very small amount of particulate but it was very fine like talc. After about 30 minutes the cloudiness in the fuel disipated in all 4 samples and the fuel looked good.

After reinstalling the carb the engine ran well.

At the end of the season we are going to drain the tank and water separator and fill it up with fresh fuel.

Lessons Learned
1) The manual flush really gave us a picture of what was going into the carb. If you are trouble shooting a fuel problem start with a fuel sample in a clear bottle.
2) Add a Racor Filter,our tank is not that old and we still had some muck to deal with I can only imagine what it is like for a 20-30 year old tank.
3) If you do work on the carb make sure you check everything. Remove / install is a lot more work than checking a few more ports and jets.
4) We could not get the Mechanical Fuel Pump Sediment bowl off and did not want to risk breaking it so this winter we will remove it and make sure it is in good order. For now I think we were able to get the bulk of the debris out of the system.
5) I may also rig up a line with a primer bulb to take a sample directly through the fuel pick up at the start of each season to be sure we did not get condensation or separation of the fuel over the winter months.

[Don Moyer]

Concord,

Thank you so much for your testimonial regarding your fuel flush. I believe if we could somehow have the entire Atomic 4 fleet complete at least one of these flushes, and then a preventative flush every third year or so, we'd eliminate 90% of our fuel-related problems.

Thanks again for your contribution.

Don