floats adjusted to specs. but not working right

[Guest]

Hey guys. just got some parts in and i adjusted my floats to factory specs. now it wants to dump gas out the overflow tubes. the float needles are good. is it possible to set them at a different height than factory and not hurt the performance?

 

[chuckycheese]

Sure

Sure

Sure, you could do that but I don't think that will solve your problem; I think it will add another one.

Is gas flowing out of both sides?? Does it do it when it's running...or not running..or both?

 

[Guest]

out both sides and it only does it when its running.

 

[chuckycheese]

Odd

Odd

out both sides and it only does it when its running.

Well, your vacuum petcock is working properly. I find it baffling that it would leak from both sides....

 

[Guest]

it does it worse when i try using the choke. its got me baffled.

 

[rustybronco]

you can try lowering the float levels by 2mm, or connect a fitting to the drain and holding it along side the float bowl and check the levels that way.

I don't know what the spec's are for your carbs, but 4.5-5.5 mm down from the gasket surface is the spec for my '80 850.

it is possible the floats don't "float" as well as they did when new.

 

[argonsagas]

When in doubt, look for an easy fix.

Even though the floats work perfectly dirt, even a tiny bit, will always prevent the needles from closing off the passage completely and gas will flow through.

Apart from float height, this is the most likely cause of that problem

 

[matt_gs450]

I posted this thread last week while I was checking my float height:
http://www.thegsresources.com/_forum/showthread.php?t=144137

I made a float gauge from a spare bowl plug and the nipple from a plastic fuel filter.

It certainly sounds like your needles aren't seating (echoing the last post above). Just to be safe, I added an inline fuel filter between the tank and carbs.

-Matt

 

[chuckycheese]

Yep

Yep

When in doubt, look for an easy fix.

Even though the floats work perfectly dirt, even a tiny bit, will always prevent the needles from closing off the passage completely and gas will flow through.

Apart from float height, this is the most likely cause of that problem

I agree with you about the dirt! But, I find it almost too coincidental that it would occur on both sides (and presumably started at the same time since he didn't say otherwise.) I'd be very surprised if the float height is the problem.

 

[frosty5011]

I agree with you about the dirt! But, I find it almost too coincidental that it would occur on both sides (and presumably started at the same time since he didn't say otherwise.) I'd be very surprised if the float height is the problem.

Unless maybe the float height was incorrectly measured.....maybe took measurement between the wrong two surfaces????

Don't know the proper height for that model, but should be checked at the following surfaces:

 

[Dave8338]

Has to be float related. Did you "float" the floats in fuel over night to ensure they are not getting logged? Otherwise I'll also suggest another check of the float height setting. :-k

 

[Guest]

I have the brass floats. they are in perfect condition. as for my float height it is supposed to be set at 22.4 +/-1.0. a while back steve and i was checking them and if you set them at that level they didnt seem like they wanted to close the needle all the way. I'm going to adjust them to 24.0 and see how that works. We origanally had them set at 25.0 but it was causing the bike to run bad so i figured i would try and put them to factory specs. I change them to 24.0 and let every one know what i get from that.

 

[TheCafeKid]

Brass floats will leak and logg just the same...Do your float valve needle have rings worn on em? If so, they're sacked...Pitch em and get new ones or it wont ever seal up right..

 

[chuckycheese]

Floats?

Floats?

I'm eager to hear the outcome but, once again, I don't think the problem is going to be the floats...it almost never is.

 

[1978GS1000custom]

this might sound silly but would it be possible that the vent and vacuum lines got mixed up at the carbs? mine has 1 vacuum line (from the fuel valve) and 2 vent lines (go to the airbox rear) and when they got mixed up when i installed them after a few beers she puked just like you described until i got them switched around. another thing is the float alignment, if you take off the floats and compare them thay all should be square in the mounting area and identical in appearence. sometimes people try bending them to adjust them and they get bent out a bit from straight alignment causing them to rub the bowl or carbs center casting with full of fuel only. just some thoughts... cliff

 

[Guest]

this might sound silly but would it be possible that the vent and vacuum lines got mixed up at the carbs? mine has 1 vacuum line (from the fuel valve) and 2 vent lines (go to the airbox rear) and when they got mixed up when i installed them after a few beers she puked just like you described until i got them switched around.

I had the same thought...

 

[matt_gs450]

I think you want them at 26mm. That 22mm value in the Clymer manual must be for some other float design other than the brass ones. And if you look at the level on my carbs (in my linked thread) with the adjustment at 26mm, it's basically perfect. About 5mm below the float bowl gasket.

I'm curious what you mean when you say the bike wasn't running well at 25mm. That could have been a mixture screw issue. Setting it at 2 turns out worked great for me.

Good luck,
Matt

 

[rkubik]

Same thing happened to me. The carb bowl vent lines have the wrong routing.

The fix is easy. Remove the vent lines, just pull them right off.