3x2 question?

[sjmodels]

The rear carb on my 3x2set up keeps getting black colored trash in the screen and needle and seat but not the center or front carb. The fuel filter and canister are spotless any ideas what to look at? New tank, filter and rubber lines. I can't figure out why only the back carb would collect crud?

[Joe-jdc]

The first thing I would check is the fuel log and make sure it is thoroughly clean.  I would also make sure the filter is ahead of the fuel log so that all carbs are filtered.   If that has been done, then are you idling off the center carb, end carbs, or some other combination?  Hopefully you are in the idle transfer of the end carb also so that the fuel is kept clean by at least using some of it regularly through the idle circuit.  The fuel hose going to that carb may be deteriorating on the inside, so I would also check that.  Is the fuel log level, so that sediment does not settle at the rear when engine is not running?  Many things to look at, but these are a few simple things to check.  Joe-JDC

[sjmodels]

Thanks for info, it is a stock factory 406 3x2 set up the filter is between fuel pump and fuel log. Every thing looks clean and the rubber hoses from the log to the carbs are less than 1 year old but I plan to change the just in case.

[cjshaker]

I would replace all your rubber from the filter on. Blow the lines or flush them as best you can including the fuel log as Joe mentioned. And if it continues, replace all your rubber before the filter also. I have ran into bad rubber hose at work where I have every piece of equipment you can imagine. Sometimes you can get a piece that has been sitting on a shelf for a long time. It might be deteriorated or just not compatible with the newer gases. Since the fuel flow won't typically be fast enough , the "trash" will pass by the first two carbs and end up being "pushed" into the last one.

[sjmodels]

[quote Since the fuel flow won't typically be fast enough , the "trash" will pass by the first two carbs and end up being "pushed" into the last one.
[/quote]

Thanks!
   Might be what has happened.  I replaced hoses blew out everything with carb cleaner, reassembled everything seemes alright now " we'll see "

[machoneman]

Modern gasolines with alcohol can sometimes cause early deterioration of the material. Take a small chunk of your new rubber tubing, put it into a small glass jar, add enough of your pump gasoline to cover it and screw on the top. Take a look at it now and them to see if the hose is disintegrating or not.