Tiny metal shavings in fuel filter

[pwgunny]

I have a 1998 Merc 150 (w/carbs.) that was rebuilt last fall. I am not getting all the power out of this motor and it sometimes stalls when I hit the throttle. It starts ok but idles a little rough. I changed the fuel filter to a clear one, and I've already cleaned out metal filings from the filter twice already. I've replaced spark plugs, but no change.
Any advice, thank you.
-Gunny

 

[Mike722]

Re: Tiny metal shavings in fuel filter

Did you notice problem after a fill up? Maybe got some bad fuel I would check your fuel tanks for the metal filings; drain and clean them if needed. I would also check the carb bowls and make sure nothing get past the filter.

I have found that a good remote fuel tank with new fresh fuel is a good way to determine if fuel problems are engine or tank or fuel related.

Hope this helps
Mike

 

[pwgunny]

Re: Tiny metal shavings in fuel filter

The remote tank as a test is good advice. I've suspected bad fuel as the cause to the performance. I've run about a tank and a half through the engine so far this season. I've tried fuel additives and stabilizers. I forgot to mention that I was getting some surges of power in the beginning of the season, but I haven't had that lately.
Just have to get a hold of a test tank now.
Thanks- GUNNY

 

[jtexas]

Re: Tiny metal shavings in fuel filter

If I found metal in my fuel filter, I wouldn't even think about trying to crank it until I'd drained and inspected the tank, disassembled the carbs, inspected the reeds, and pulled the cylinder heads. If I was a better mechanic I'd open up the crankcase, too. If it's a metal tank I'd replace it for sure.

When you say surges...a gradual RPM increase & decrease points to fuel, but sudden changes like throwing a switch is electrical.

I'd want to do a compression test and spark test before anything else...but in your case, with the metal in the fuel...I highly recommend taking those carbs completely apart, soak 'em in carb cleaner, but especially, blow out all the passages with compressed air. Any sign of metal shavings in there...

I guess I could be overreacting...

 

[pwgunny]

Re: Tiny metal shavings in fuel filter

Thanks for the replies. I haven't had a chance to get down to the marina. Lots of rain this weekend.
I am a little worried by the Jtexas response. To be more clear the bits of metal were tiny, like glitter.
Would this be the source of my lack of power? Could the metal bits be coming from the fuel pump?

Thanks, -Gunny

 

[jtexas]

Re: Tiny metal shavings in fuel filter

gunny don't panic on account of my reaction...I don't have actual experience with finding metal in fuel...or what the actual downside would be if any got through the filter...might would just sink to the bottom of the carb bowls...rivirea had a good suggestion...if any did get through some would probably be there still.

"Tiny like glitter" makes me think of a metallic coating coming off something, like a part that's been chromed?

Surprised you didn't get more response on this one...maybe try posting in "Outboard non-repair" or "Boat Topics" to get a wider range of viewpoints?

I'm curious to hear how this one works out.