1979 gs1000 with bst34ss flooding

[Guest]

I've read almost everything there is on this topic and have been rebuilding carburetors of all types for most of my life.

1. Float settings from 12mm to 24mm in 0.2mm increments (yes they came off a lot)
2. Replaced all floats
3. Replaced all float needles/seats/o-rings
4. Replaced all rubber carb connection tubes
5. Replaced all throttle shaft seals
6. Replaced bowl o-rings
7. Replaced brass choke plunger guides and plungers

#3 & #4 hold good level at 15mm #1 & #2 are flooding badly



I'm stumped

[Nessism]

Carb rebuild tutorial linked in my signature. Not following this 15mm business.

Sounds like something wrong with the float needle and seat.

Measure fluid level.

[gs45082]

Carb rebuild tutorial linked in my signature. Not following this 15mm business.

Sounds like something wrong with the float needle and seat.

Measure fluid level.

The tutorial link is bad, is it anywhere else?

[steve murdoch]

Try here , SV.

http://zeus.mtsac.edu/~cliff/storage/gs/Mikuni_BS-CV_Carburetor_Rebuild_Tutorial.pdf

[gs45082]

Thank you!!!

Try here , SV.
http://zeus.mtsac.edu/~cliff/storage...d_Tutorial.pdf

[Svbob]

Carb rebuild tutorial linked in my signature. Not following this 15mm business.

Sounds like something wrong with the float needle and seat.

Measure fluid level.

Measured fluid level with clear hoses, #3 & #4 hold fine. #1 & #2 leak no matter what level I set the floats at. Brand new Needles, seats, floats, and o-rings.

I've been rebuilding carbs for the past 20 years and have never seen an issue like this. I even dismounted the carbs and built a small stand that will allow me to bench test and change the angle that the carbs are sitting at... no help either. Went so far as to find a 1987 Gsxr 750 and measure the angle that the carbs sit. still no help.

[gs45082]

Measured fluid level with clear hoses, #3 & #4 hold fine. #1 & #2 leak no matter what level I set the floats at. Brand new Needles, seats, floats, and o-rings.

I've been rebuilding carbs for the past 20 years and have never seen an issue like this. I even dismounted the carbs and built a small stand that will allow me to bench test and change the angle that the carbs are sitting at... no help either. Went so far as to find a 1987 Gsxr 750 and measure the angle that the carbs sit. still no help.

Have you tried just lining up the bowls up and just pouring a little gas in each? I'm starting to wonder if something in a casting is broken.

Im elbow deep in my carbs chasing a leak, it was leaking at the tee so it got soaked in armor all and its airtight.

[Nessism]

How about removing one of the float bowls on a leaking carb and then feeding fuel into the main T? You can lift up the offending float to see if it stops the fuel.

Where did you get the needle, seat and O-rings? Sounds like you got some bad parts.

[Svbob]

Soooo....

...after a long hiatus from working on the bike I am happy to say she is finally running! Flooding issue was traced to some spiderwebs in an upper vent passage. I guess the blockage was causing a siphon and preventing the floats from closing. Currently with a piece of fabric to serve as a makeshift air filter and to provide some restriction. Got the timing dialed in, she wouldn't idle well. 1/2 turn out on each adjuster 2.75 total, and now she purrs nicely. Pulls very hard up to redline, this bike wasn't scary before the carb swap now she picks the front up into third, definite performance boost and scares the hell out of you with 1979 brakes. She was so smooth I don't think I'll need to rejet.

Currently has BST34SS with 128 Mains and 35 pilots, clip in the middle, washer underneath. Previous owner drilled the slides. Gonna run some uni pods and factory pipes until I can afford a delkevic header.

[Fjbj40]

Stock internals or dynojet kit?

[Svbob]

Stock internals or dynojet kit?

I'm pretty sure the carbs i got from ebay had a DJ kit in it already. IIRC they were 87gsxr-750 carbs