'77 gs750, need a float: or 4

[Chainsaw]

Through some sort of miracle, I got my gs750 running today. And running good too. Except one thing, The #3 carb pours fuel out of the bowl drain tube. I adjusted the float 2 or 3 times (way beyond spec) and it still drained. The only logical answer I can think of is a bad float. So I called up the local Suzuki dealer who quoted me $22 per float. 22 bucks ain't bad but if I'm going to replace one I'd like to replace them all...

My question is:

Does anyone know where I can get a set of floats cheaper than that? Or should I just bite the bullet and buy them? Or perhaps, should I just buy one to replace the bad one?

Any input is appreciated. I've checked Z1, BikeBandit, and Flatout. I can't seem to find floats (but I may be too drunk).

Thanks guys,
KC

[TheCafeKid]

Chainsaw...Sounds more like the float valve than the float itself. If you take your float out, the only time it will be bad is if it has a hole in it somewhere and is taking on fuel. You'll know, it will prolly still have fuel in it. $22 bucks each isnt bad. However, you may be able to buy a set of VM carbs off ebay for cheaper than $88. I, myself, would check the float valves FIRST. They're cheap. Secondarily, our 77 "B" VM's are different from everyone elses. The slides arent the same. The needles dont install the same, dunno bout the floats. (Ask me how i know) At any rate, try a float valve. If that doesnt work, i would get the NOS parts, simply cos they're new, and you know they're good. Just my 2 coppers...

[Chainsaw]

By "float valve" do you mean the needle that the float closes when it, well, floats? If so, shall I move the float and valve over to another carb to see if the over-flow follows it?

[TheCafeKid]

yessir thats the one And that would indeed tell you if that were the case.

[TheCafeKid]

BTW did you replace your orings when you did your carbs? You will want to make sure that the lil red gasket that sits under the float valve seat is good too. Usually are re-useable so long as they arent broken or anything, but if its not under there, it will leaky leaky too.

[chef1366]

See if the float actually floats. Also weight them and see if that one is heavier.

[Chainsaw]

BTW did you replace your orings when you did your carbs?

Yessir, got them from cycleorings.com

[tone]

good advice from the cafekid & chief
check the float isnt punctured first by floating it in a can of fuel then look to the needle valve & also the seat a small amount of wear can cause these symptoms even a bit of dirt/ rust could do it

[Bizcocho]

By "float valve" do you mean the needle that the float closes when it, well, floats? If so, shall I move the float and valve over to another carb to see if the over-flow follows it?

I think you have to move the needle AND seat together to be sure. I'd leave the float where it is to separate the two possibilities. But, as others have mentioned, you can test the float for leaks and be confident of whether it works.

You can also test the float valve by supplying gas to the carb, holding up the float, and noting whether gas flow is stopped. That's probably a lot easire than reassembling everything to see if the problem moves.

[hampshirehog]

The best way to test if you've got a punctured float is to give it a shake and listen, right up close to your ear. If its got any liquid in there you'll hear it.

[Chainsaw]

Update:

I had a little bit of spare time at work today so I pulled my carbs again and soaked the floats in gas for about, oh, 9 hours. None of them sank at all so I think I'll rule those out. If I have time tomorrow I'm going to swap the needle and seat to another carb and see what happens. I visually inspected them today and didn't see any debris or rough spots, so tomorrow will be the true test.

I found the needles at Z1 ($15 for a 6-pack, not bad), but if I need to replace the seats, does anyone know a good place to get those?

Thanks for the help guys...

KC

[dardoonk]

Chainsaw, I just had this problem with my 77. I kept trying to adjust my floats and couldn't get the #2 from spilling out. I had just completely rebuilt them and was sure all the new parts were fine. After pulling them twice and getting nowhere, I took them off for a third time and swapped out the brass jets that came with the K&L kit for a set of real Mikuni ones and solved my problem.

I didn't change out the little needles, so it looks like the aftermarket jet must not have been fitted properly.

Note to self: Use only "real" Mikuni parts in the future.

[TheCafeKid]

I may be wrong, but im pretty sure Z1 sells the float valve seats. Perhaps not. But i know they sell jets, and im pretty darn sure they're actuall MiC jets too..

[chef1366]

This place is a little pricey but have everything you need.

[Chainsaw]

Well, I swapped the needle, seat, and float between the 3 and 4 carbs. I put everything back together, set the carbs on a vise with a length of feed hose and filled them full of gas. After about 5 minutes I saw no leaks so I put them on the bike and rode around the parking lot for a few minutes. I pulled back into the shop to find the #3 leaking again AND #1... Just to be sure, I looked real close to see if it was maybe the gasket leaking down to the overflow tube, nope, the bowls are dry, the gas is coming out of the tube.

Something peculiar I noticed while the bowls were off was a plug of some sort, in the body of the #3 carb that appears to block the vent going to the top of the carb. I may snap a picture tomorrow if I go into work, but does anyone know what thats for?