Debris in Fuel Filter

aero3113

Last Thursday we took a half hour ride to Ocean Beach Fire Island for the day. On the way there it was just myself and my wife, full fuel, 1/4 water and 1/4 waste. I could only get the boat up to about 4000-4200 RPM's when I usually get 4600 for WOT. The boat came out of the hole and up on plane no problem. On the way back I had 2 more adults a 5 year old and a lot more gear. The boat once again had no problem getting up on plane but could only reach 4200 RPM's. Today I replaced the fuel filter and dumped it out into a small bucket. There was already some light dirt in the bucket(I should've cleaned it before hand) but I noticed what I thought was water. When I got home I looked at the fuel from the filter and it was a very fine grit that must have been mixed with water. In the pic you can see how much was in it (upper left) Do you think this could have been the cause of my issue? How much debris in the filter can cause issues? Unfortunately I wasn't able to take the boat out on a test run today.

Michael T

I don't like any grit in a fuel filter but at least (hopefully) the filter did its job. As for your rpm drop. You lost 400 rpm but you had added a lot of extra weight. You could also have been running against a different current, surface conditions (even slight affect rpm) or even a change in humidity can affect rpms. In my opinion, in the absence of any other data like overheating etc., I'd say that loss of rpm at your "top end" with a big extra load was nothing to worry about, in fact I'd say it was normal.

Serenity

Aero--we boat in the same waters. Did you check your props? This time of year you have to run your boat once a week at the very least. A few years ago I did not run mine for 2 weeks and when I did run it--I had the same issue as you. I anchored in shallow water near the beach and saw the props were fowled with barnacles. Since that day I run mine at least once a week. Even if it is a 15 minute run on plane to clean it all off. I have not had an issue since that time a few years ago. Just a thought anyway. Good Luck.

Michael T

I forget how lucky I am to only have to deal with some algae on the hull!

aero3113

Serenity, the boat did sit 2 weeks before we went out but the prop was the first thing I checked when we pulled into ocean beach.

Serenity

My props were messed up when I had the issue. Maybe it is another issue if your hull and outdrives are clear. Good luck.

aero3113

Looks like the filter change did the trick, back up to 4600 at WOT  . I did take one step back though. I was anchored at Barrett beach Fire Island today and it is real shallow there (Also the water was very rough today) I only put the drive half way up, came back to the boat after a great day on the beach to find my skeg on my drive broken. Now I have to order a replacement skeg and have it welded on. Luckily there not that expensive! Boat ran great back home though!

Michael T

Sorry to hear of your distress, aero! I'm pretty sure I posted this before. Anchoring near beach or on a sand bar can be very bad for your boat for a number of reasons. Here's one that had a friend and his techs stumped. He was having significant overheating issues after an afternoon of anchoring on a sandbar. The techs were trying everything. Then it turned-out that he said he "might" have been running the engines to "demonstrate" his through hulls and charge his batteries because of stereo amp use. Yeah, sure! Long story short, the block and hoses were full of sand, impellers ruined and pump bodies sanded and scored. a real mess. Anchoring near beaches or sand bars or doing a "New Jersey Dredge" are all risky business boating wise. :-)