Why is rusty tank bad for carb?

[dontlikeoc]

Why exactly is a rusty tank bad for carbs? Doesnt the petcock filter catch the rust flakes before they reach the carb?

A recently picked up XS1100 Special has medium - may or may not have fallen off flakes at the bottom - surface rust inside the tank. To see how the engine runs, I filled it with gas and ran a few blocks. Also, I am thinking of riding it back from the shop once the electric problems are taken care of. (I am planning to do electlysis rust removal once other issues are addressed).

When/if you work on the carb, what exactly are you looking for in case of a rusty tank, rust chips?

[TADracer]

IMHO, chemistry of rust and gasoline aside (if any) the larger flakes should have no real effect if they are screened out, its the smaller stuff your screens just will not catch. Even with 40 micron filters a rusty tank will show deposits of fine rust dust in the bottom of your carb bowls. 40 microns is about half the width of a human hair and can just go right through any of the passages in the carburetor without a problem but there are plenty of little nooks and crannies (yep, its a technical term) where this stuff can build up over time and possibly affect the carb tune.

With any fuel system, the cleaner the fuel the better.

[Lucien Harpress]

I can speak from experience- no matter how many screens you have between your fuel tank and carbs, if there's a bit of rust in your tank, it WILL find its way into the carbs! Combine this with the fact that (apparently) these carburetors will refuse to work if they even catch the tiniest whiff of rust, and you can see why the best course of action is to just clean out your gas tank.

The only way I was finally able to stop my bike from gumming up the carbs every two days was to install a pair of in-line paper type fuel filters. Even this is a temporary measure until I can get my new tank refurbished. When I bought my bike I neglected to check the inside of the tank before dumping in half a can of Seafoam. All I accomplished was knocking most of the rust off the inside of the tank! Was dealing with THAT little incident for months.

So do yourself a favor- clean that tank out ASAP!

[TomRodgers]

Think of your tank, lines, and carbs kinda like your own digestive system....

You dont want indigestion, and neither do your carbs. if someone gives you a glass of good drink of any kind( preferebly cold, yummy and free!!!) and put a bunch of crap in it, and told you to drink it, lets say through those same petcock screens...would YOU?....I dont think so. SOOOOOOO clean the tank the best you can. Save yourself some headaches later on. Besides, if you dont, and gunk starts building up in the carbs, even though its not hard to do, its just a pain in the a$$ to do...

[dontlikeoc]

Thanks for all the advice. I should probably better get the bike towed from the shop.