Weird fuel delivery problem! (I think!)

[VORTEX1212]

I just finished cleaning up my carbs on my 93 600f kat. I took her for a spin and after running for half hour on the high way she quit, I pulled to the side and tried to start the motor with no luck, I noticed two carbs were not working, the two on the left,a buddy of mine picked my bike on his pick up and we went to my house, i decided to pull the carbs again, clean them up again just in case, checked the settings, and re-sync the carbs, the filters are brand new, and also the fuel petcock (brand new original suzuki, not rebuilt) when I put it all toghether and started the bike the same problem with the two carbs of the same side were cold, I lokked at the filter that feeds those two and it was empty as compared to the other one, I checked the petckock on prime position and fuel was coming out both sides ok, when I reconected the lines all 4 carbs were working perfect! I took her for a test spin, and ran perfect lots of power etc, after a while the bike quit running again, just in case i tried all positions of the fuel petcock, and made sure the vaccum line to the carb. was attached ok. I set the petcock to prime and after a while it started just perfect again! Whats weird is that this time it was the other two carbs that quit working!!!! I dont know what to make out of this, maybe my new filters are the worng type? ( I use the paper type). Your input on this one would be really aprecciated! Thanks! Harry

[letsride]

Fire it up for a few. Turn it off. Then go to the bottom of the bowls remove the bowl screws at the bottom and see if fuel comes out. You dont have to remove the carb. Let us know if fuel comes out of all carbs

[VORTEX1212]

I forgot to mention that when I had the problem I did opened the bleed crews ond on both ocations, first on the two left and then on the two of the right the bowls were empty.

[arsenic]

ok, lets look at this as logical as possible. A 93 600 has 2 fuel lines. If 2 carbs are not working than 1 fuel line is not delivering fuel.
1. - pet cock, you checked that, it's working
2. - fuel lines before the filters, make sure they are clear.
3. - filters them selves
4. - fuel lines after the filters
5. - main jets.

[VORTEX1212]

I dont think this maybe a float related problem due to they failed in pairs, first the two of the left and next the two of the right side, and then the bike ran super for a while, well I think.....

Fuel lines are brand new also!

[letsride]

sounds like a fuel delivery problem. Also check vent tubes. Tank and carb. If they have them

[VORTEX1212]

If the vent tubes, the two hoses on the carbs on top that they are not connected to anything, are kinked or blocked will cause a fuel delivery problem?

[letsride]

Yes it can

[dpasch]

to me it sounds like there is something in the petcock blocking the fuel line passage, have you taken the petcock apart an clean it yet?

[VORTEX1212]

Well I have not taken it apart first is brand new, nor even two days of use and I checked if fuel flows ok out of it and it does in all posotions.

[Newbie2it]

Just a guess here on a possible reason.

Fuel filters laying horizontal or near to Probably.

I have a 93 750 I added filters and tried to get them suckers as close to vertical as possible But I always found that it would develop a bubble in it that would never burp out to the tank. Hence it would actually impede the incoming flow of gas. In the end I just removed the damned things. I was using the stone a.k.a. wrought brass conical filters which flow more than paper. I didn't have any rust issues with my tank however (dont know if you do or not) But I had added mine for preventative measures and thought it was a good idea.

On removing them, that within itself was the best idea, The bike had more power on the higher end without them since its getting the fuel it needs at the right rate.

Just my two cents on a filter on a pre that wasn't designed for one.

[catfish]

my bike ran like crap with fuel filters in there ('93 Kat). i think you just explained why. try pulling them out and see if it rides?

[KenpachiZaraki]

yea, i also have a pre, and i had the filters on it, ran like crap. i dont know and why it happens, but i dont think pre's should have a filter. the world is much safer that way take them off and try it like that. if you have rust in your gas tank, my guess is that it will run great for a while until you have to clean the carbs because the pilot jets got full of rust sediment. yea i know the feeling

[arsenic]

yeah pre's do not come stock with filters. I didn't think it was a problem to add them, but I guess it is

[Black_peter]

Just a guess here on a possible reason.

Fuel filters laying horizontal or near to Probably.

I have a 93 750 I added filters and tried to get them suckers as close to vertical as possible But I always found that it would develop a bubble in it that would never burp out to the tank.

I'll support that theory..