Look what I found in my fuel pump!

[mkino]

1991 Mercruiser 454, carbureted, mechanical fuel pump.

This is my fuel pump, it died in January. The sandy looking stuff turned to dust when I rubbed it between my fingers.

I replaced the pump and the fuel filter, but there seems to be an lack of fuel flow, had to bump up the idle to get it to run, then under load, it started surging and backfiring thru the carb. I checked the fuel pickup and anti siphon valve, all clear. I also siphoned out several gallons of gas to see if there was sediment, nothing.

I'm guessing some of the crud in the picture went into the carburetor. Any chance gumout or something similar can clean it out? I tried some already and it still backfired a bit when I hit the throttle, but this was just running it on the hose, not under load. I just rebuilt the carb last year and I'm not excited about doing it again...

Any ideas?

Thanks!

 

[Watermann]

Re: Look what I found in my fuel pump!

Sounds like some of the crud could have gotten into the carb jets. Mechanic is a can rarely if ever fixes anything for me. Do you have a fuel/water separator filter?

 

[mkino]

Re: Look what I found in my fuel pump!

Sounds like some of the crud could have gotten into the carb jets. Mechanic is a can rarely if ever fixes anything for me. Do you have a fuel/water separator filter?

Yes, I replaced it when I replaced the fuel pump. It was all messed up, looked like it had rust in it. Bad gas out there!

 

[acdc96]

Re: Look what I found in my fuel pump!

Hook up a portable tank and try running it off of that. Also, clean the fuel lines.

 

[JustJason]

Re: Look what I found in my fuel pump!

You should plant those bits in the dirt and see what grows.

 

[thumpar]

Re: Look what I found in my fuel pump!

Just rebuild the carb. The kits are usually on around $20. While you have it taken apart you can clean everything our really well.

 

[mkino]

Re: Look what I found in my fuel pump!



I found on another thread that there is a filter where the fuel line feeds into the carb.

I'm guessing that this may have impeded the fuel flow just a bit!!!

YES!!!!!!!!!!!!!!!!!!


So the moral of the story - if you find junk in the pump, it's probably in the final screen filter too.

The source of this? Ethanol that destroyed my fuel filter (from my trip to Lake Powell last August), sent bits of the filter media upstream, causing big problems (new filter, new fuel pump, missed the whale watching season here in southern Cal).

Happy boating all!

 

[UncleWillie]

Re: Look what I found in my fuel pump!

... Ethanol that destroyed my fuel filter (from my trip to Lake Powell last August), sent bits of the filter media upstream, causing big problems (new filter, new fuel pump, missed the whale watching season here in southern Cal)...

Unless you haven't replaced the fuel filter since the 1980s, Ethanol may tend to clean the filter but it won't destroy it.
It really isn't the "Alien Blood" that some people claim it is!
Everything in your 1991 Boat is built with Ethanol in mind.

 

[mkino]

Re: Look what I found in my fuel pump!

Unless you haven't replaced the fuel filter since the 1980s, Ethanol may tend to clean the filter but it won't destroy it.
It really isn't the "Alien Blood" that some people claim it is!
Everything in your 1991 Boat is built with Ethanol in mind.

Well the filter was destroyed, rust colored junk in it, and the guy who manages my houseboat (and 40 other houseboats at Lake Powell) says ethanol destroys fuel filters. I think he's a pretty good source...

 

[HT32BSX115]

Re: Look what I found in my fuel pump!

Well the filter was destroyed, rust colored junk in it, and the guy who manages my houseboat (and 40 other houseboats at Lake Powell) says ethanol destroys fuel filters. I think he's a pretty good source...

yeah.....Ethanol gets blamed for a whole lot of things! (especially when the "mechanic" cannot diagnose the problem!!)

Chances are, your problem is not ethanol.

 

[Pete104]

Re: Look what I found in my fuel pump!

yeah.....Ethanol gets blamed for a whole lot of things! (especially when the "mechanic" cannot diagnose the problem!!)

Chances are, your problem is not ethanol.

Really, what makes "white rust" then? Some other additive that our beloved government puts in?

Ethanol ATTRACTS moisture! Physically pulls moisture in thru the tank vent & put thru the system gets the results shown previously! All filters require frequent replacement, more often if the unit goes unused for weeks at a time. As the fuel evaporates, the residue is left behind.

 

[UncleWillie]

Re: Look what I found in my fuel pump!

Really, what makes "white rust" then? Some other additive that our beloved government puts in?

Ethanol ATTRACTS moisture! Physically pulls moisture in thru the tank vent & put thru the system gets the results shown previously! All filters require frequent replacement, more often if the unit goes unused for weeks at a time. As the fuel evaporates, the residue is left behind.

Asking two questions is not the same as providing an explanation.
I will assume you mean the "White Rust" that forms on Aluminum. Aluminum Fuel Tank???
It is Aluminum Oxide and is the combination of Aluminum and Oxygen, No water or Ethanol Needed, for that reaction to take place.

Ethanol in your tank will dry the air in the tank.
Ethanol does not have a mating call that attracts the water in the air outside of the tank.
The lighter hydrocarbons in the gasoline are constantly evaporating under normal atmospheric conditions.
The flow of gasses through an old school vent line is predominantly OUT not IN.
This is easily demonstrated by sealing the tank vent and noting that the tank tends to self pressurize.

All fuel tanks made after 2010 (CARB) will not vent OUT except for highly excessive pressures
and will only vent IN to prevent the tank collapsing from the consumption of fuel by the engine.
Don't we just love these Ethanol threads?op2:

 

[HT32BSX115]

Re: Look what I found in my fuel pump!

Ethanol ATTRACTS moisture! Physically pulls moisture in thru the tank vent

I think I may disagree............

Living in the W Wa for more than 25 years, leaving that evil E10 in vented fuel tanks all that time.....AND I'd say that in W Wa, we have a fairly high humidity year round (because it only seems to stop raining right when it's getting ready to start again!)

So Keep worrying about E10 in the tank, keep telling others to worry, etc...... I just pump it in, run it to about 1/4 tank in SEP, fill it up in MAY and go boating year after year. I don't use any snake oils either.




Others disagree too, including people who actually have some experience and hard science to back them up.

The Myth of Condensation in Fuel Tanks by David Pascoe: Boat Maintenance, Repairs and Troubleshooting

 

[thumpar]

Re: Look what I found in my fuel pump!

I remember finding "white rust" in my motorcycle carb when I was a kid. That was long before ethanol.

 

[HT32BSX115]

Re: Look what I found in my fuel pump!

I remember finding "white rust" in my motorcycle carb when I was a kid. That was long before ethanol.

Yeah. if you evaporate any gasoline you get all sorts of "stuff" if you let it sit long enough. There is an ASTM standard for it too. ASTM D381 - 12 Standard Test Method for Gum Content in Fuels by Jet Evaporation

The bottom line is, if you're going to "pickle" engine, you should probably drain the fuel out of the carb. Pickling should be considered if you're going to let an engine sit for years.

If you're going to only let it sit for a winter, you probably don't have to. I never have......