Gray sludge in gas tank / carb?

slomo

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Wow, never seen this pot metal dissolving trick. Lot of wise people on this site.......
 

VRR.DYNDNS>BIZ

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When it comes to gas these days, we have all seen everything. algae, mold, metal forming oxides, plastics and rubber decay, and far more. Ethanol and additives and time are the enemy. If it runs on gas, in time problems will evolve unless it is dry. A few years back I had conversations with the R&D departments of both Walbro and Zama. Since 1985 they have researched materials to withstand these issues to no success.
 

LKB

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Thanks for chiming in.

OK, so my problem stems from water or something ethanol-related contaminants dissolving stuff. Ergo:

1. What solvent/cleaner do people recommend to clean out this dissolved pot metal grey crud from the gas tank? And once I have it clean, should I treat the inside surface with anything? Or should I just chuck it and replace with a cheap plastic aftermarket one?
2. Is it even worth trying to clean the cheap aftermarket carbs once they‘ve sucked up some of this crud?
3. Big picture, what’s the advice for the best way to deal with small engines that are used infrequently (quarterly or even less frequently)? I‘ve now found a source of ethanol free gas nearby, and I try to run the engines until they are completely out of gas, but for things like my chipper, tamper, and pressure washer that might go a year between uses, what are best practices?
 

7394

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Test your gas to be sure it is 100%...
 

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Alton R

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I have a TroyBuilt power washer powered by a 4.5 B&S engine that uses the 795469 carb (the kind that has a priming bulb and mounts directly to the gas tank, which has a mounting plate with machined channels that forms the bottom of the carb).

I recently have had all manner of problems getting it to start. Removed and flushed out the gas tank (soaked with kerosene, then rinsed and completely dried), changed oil, replaced the carb, carb gasket/diaphragm, spark plug, air filter, etc. (kits with all that are less than $20 on Amazon). Ran fine once, but the next time I needed to use it, it would not start. Took it apart and the gas tank has a light gray sludge everywhere (even on the sides of the tank — they look almost like crystals), which needless to say had completely stopped up the carb.

I also had exactly the same thing happen recently with my gas weed eater. But my lawn tractor (Cub Cadet) is using the same gas and is running fine (knock wood).

What’s weird is that I’d been running all my stuff for years on standard regular gas (which almost certainly had some ethanol in it), but recently had found a place nearby that sells ethanol free regular gas (mostly for boaters) that I have started using in my small engines.

Any idea what this gray crud is and why it is forming? And what I can do to prevent it?

thanks,
LKB
Austin, Tx.
I would flush out the gas tank. I would check my gas can also.
I would never trust what comes out of a gas station pump. Pore your fuel into a glass container first before you put it into your machines. I had to replace my wifes gas tank because of trash and water. A cars fuel tank has a baffle in it. You can't get that junk out.
Sounds like your places you buy fuel from is your problem.
 
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