Bs38 carb gasket orientation, and sediment in bowls...

[cafetools]

I searched and came up empty on verifying gasket position. Also these gaskets (ordered from ebay) do they need to be trimmed or anything?


Also I am extremely frustrated at how I am getting sediment in my bowls. Quite a bit, which I'm sure is why it's running bad.

I replaced the fuel filters with some paper ones again, and somehow dirt is getting past. Should I use the little ceramic ones? It seems like I get better flow with paper.

 

[TwoManyXS1Bs]

On your carb, you can run the bowl gasket flipped either way. Earlier bowls have an overflow tube that goes thru that hole.

As far as sediment is concerned, you could drill sediment traps in your drain plugs...

From here:

http://www.xs650.com/threads/revers...lot-circuit-idle-jet.42002/page-2#post-455856

 

[5twins]

But I think the big question here is, where is all that junk coming from? I think your gas tank needs a good cleaning.

 

[cafetools]

I cleaned the tank via vinegar method but there's still some rust that gets knocked loose I'm guessing.

I'm using large paper filters with a 40 micron rating. I'm thinking about these filters at Lowes, they are 150 micron. Will they be better?

 

[TwoManyXS1Bs]

The smallest openings thru which the fuel flows is,
- The sliver of opening between the float valve and its seat.
- The pilot jet, an orifice size of about 250 microns, on 76-79 carbs.

Large particles seem to easily pass thru the float valves, but there's always the risk of something getting temporarily lodged in there, causing overflow.

The 150 micron rating of the 2nd filter implies that any passing particulates will pass thru the 250 micron pilot jet. However, a recent filter research study showed that media filters have allowed particulates at least 2x larger than rated to pass.

Your call...

 

[cafetools]

I think I found something that will help me and also others! Check out this chart. The paper filters I was using were rated at 150 microns, according to this chart that will let something as large as table salt specks through. That is not acceptable. Im going to find something in the 50 to 40 range which sounds better.

Chart:

 

[cafetools]

I also want to state that I'm not using my plastic petcock screens. Which actually make a big difference. So everything in my tank travels south.

 

[ThatXS650Guy]

Have you considered lining your tank? I fought this for a while on my GPz and solved the issue with a quality 2-part tank liner.

 

[member28833]

I also want to state that I'm not using my plastic petcock screens

Is that a temporary or are you intending to run with out those internal tank screens ? Those could be found locally easily I would imagine.

 

[member28833]

 

[cafetools]

Have you considered lining your tank? I fought this for a while on my GPz and solved the issue with a quality 2-part tank liner.

I did the vinegar treatment, it looks good now. But even the smallest amount of debris are bad for carbs.

Is that a temporary or are you intending to run with out those internal tank screens ? Those could be found locally easily I would imagine.

My plastic petcock prefilters were torn. But having them working would probably allow me to use these big paper 140 micron filters because it would stop dirt before going through the petcock. I am kind of fed up with my vacumm petcocks. So I am not really willing to buy new plastic screens for them right now. I would rather try and find a non vacuum petcock to buy with the screens included in that price.

I am going to go to the hardware store today and buy those white 40 micron filters.

 

[member28833]

I am kind of fed up with my vacumm petcocks. So I am not really willing to buy new plastic screens for them right now.

Understood. Watching your progress and cheering you on !
-RT

 

[5twins]

Unfortunately, reports on the filter screens included with those aftermarket manual petcocks are pretty bad. Apparently they are prone to falling off and/or deteriorating quickly. Personally, I don't run any added filters. I rely on the stock petcock screens and so far have had no issues.

 

[XSLeo]

A lot of those lawn mower filters you get at hardware stores don't hold up well on bikes They tend to split where the two halves come together. Others have reported the same thing. I have gotten be like %twins and just depend on the stock screens. Clean tank and good fuel help a lot.
Leo