Importance of fuel filters

[triton28]

I finally got around to prepping the spare carburetors I have bought and thought perhaps a photo of the residue from some carburetor interiors may be of interest.
The exteriors of all the carbs were water based degreaser cleaned before disassembly. After disassembly, floats/jets/gaskets etc, the carb body interiors were water based degreaser cleaned but NOT the float bowl interiors as I wanted a fair representation of the amount of residue inside a carburetor.
These degreasings got rid of the obvious exterior road grime and oily residues.
Then came the new can of unused solvent based methylene chloride, xylene, benzene etc. etc. we all have come to love/hate, known here in Canada as Kleen-Flo 651 Carburetor and Metal Parts Cleaner. It is probably similar to your U.S. available product "Berryman's Chem Dip".
A word of caution if one chooses to use these solvent based products; proper ventilation, rubber gauntlet gloves, disposable arm sleeves, a good rubber apron, safety glasses and a "nuisance organic vapour" respirator are recommended. I personally will not use this chemical without these items. IT STINKS to high heaven so don't get it on your clothes/person and do not use indoors without adequate ventilation. Believe me, everyone will notice when you use this stuff. Be forewarned, it is dangerous!
Back to the importance of fuel filters;
I thought how clean the carbs looked after the water based degreasing but, since I can't see into the idle/starter drilled passageways, I wanted to soak all the bodies and float chambers in this killer carb cleaner, 4 bodies/bowls at a time, for 24 hours each.
After a dip, the bodies/bowls were washed down with the water based degreaser, rinsed in clean water and blown dry.
It was amazing the difference between using only the water based degreaser, versus using the water based degreaser followed by the solvent carb/metal parts cleaner. The aluminium and brass was markedly brighter and appeared cleaner just as if the carb bodies were on an assembly line after having been unwrapped from Kei Hin manufacturing. Absolutely spotless.
But I digress.
After having repeated the process for the 4 sets of carbs I strained the 651 Cleaner through 2 cotton cloths, the last of which is shown on the left lower of the photo. Then I restrained the cleaner through a dozen coffee filters, one of which is similar in deposit amount as the other 11, and is shown on the lower right.
As one can see from the filtering of the cleaner there was a large amount of residue left inside the carbs.
Not knowing the history of the carbs, but having seen the float chamber insides, I can only surmise that these carbs were not fed with clean filters in place. I should remark though that the float bowls were not full of crud but rather small amounts of that dull red coloured residue so often seen in float bowls.
My conclusion is that the majority of the crud left on the solvent filters/strainers came from the brass fittings, hidden nooks and crannies, and jet passageways, deposited onto their surfaces by dirty gas. Hard to believe that much crap was in those carb bodies even after having been water based degreased.
So remember this photo when wondering whether or not to replace that fuel filter on a regular basis.
Next step is to finish ultrasonic cleaning of the 3 unassembled sets of carbs, new carb kits and be done with this operation.
Lots of spares inventory here,
Dave

[Lucasind]

Oh yes Dave.....They do get awful looking on the inside, good tip on replacing the fuel filter on a regular basis too . Keeping your bike "going down the road" is also a benefit , keeping fresh fuel flowing through the carbs is the best ! Bikes that sit around unused most of the time are the candidates for the worst looking carb interiors. Your collection of carbs look great !

[sheiserman]

I've always left the bowls sit with treated fuel over winter. Bad idea?

I install a new fuel/ air filter every spring.

[triton28]

Hello Sheiserman;
Any riding weather yet in Iowa?
There are as many theories about leaving/not leaving gas in over the winter as there are opinions, and I don't think either way is wrong, just what one prefers to do.
Myself I always top up the tank with Seafoam treated gas and then drain the floats.
I don't think an over the winter layup with treated gas would cause any problems, but that is just an unfounded opinion on my part.
It does seem as though the 6 month or longer unused time frame is where the evaporation process leaves gum and varnishes in a float bowl left to stand with gas in it.
I too change the fuel filter every spring with a new John Deere unit, but with a K&N air filter all I do is check it for obvious dirt and every second season I clean and oil the air filter.
I just came in from shovelling 6 inches of wet snow, c'mon Spring.
Dave

[sheiserman]

There’s been a day or two that have been warm enough, but that is about it. I haven’t ridden yet though. We got another couple inches of snow today so it won’t be this week either.

I stored the bike at a dealer the first winter, and they leave the treated gas in the carbs. So either it’s ok or a way to strum up business.

When I replace the air filter in the spring it still looks clean.

[SgtSlag]

I've been SeaFoam'ing my bikes since 2006: three different bikes, all stored over Minnesota's Winters, with treated gas in the bowls, and the tank. I'm been down to one bike since 2012, but I just fired up the Voyager XII two weeks ago: mileage really sucks with the (most likely over-)treated gas, but I never had a carb issue on any of my bikes since I got them, and I had them all cleaned, and balanced, preemptively. I run SeaFoam through a couple of times in the riding season, just to ensure the fuel system is dry, and clean. I never drain the gas for storage; I treat the gas, run the bike for a few minutes to ensure the gas in the bowls is treated, and then I top off the tank after I shut it down, to eliminate air space and condensation, over the Winter. Never had a problem. Been doing this on the Voyager since 2011, so seven years, thus far. Did have to replace the fuel pump, last year, but that was age-related, not fuel-related (IMO: 1993 model). Just my experience, and opinion -- worth exactly what you paid for it. Cheers!