I need help! GT380 dies when I give it any gas.

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digitalintrospect
On the street
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Joined: Tue Jan 31, 2012 3:50 pm

I need help! GT380 dies when I give it any gas.

Post by digitalintrospect »

GT380 dies when I give it any gas.
It was running a little sluggish and not starting back up once it was warm, so I decided to just clean the entire carburetor.
I took everything apart and cleaned it today, and then put it back on my bike.

When I first started the bike it sounded great. I put the choke on "run" and I gave the throttle just a little gas and it died instantly.
It started back up on the first try and when I gave it any gas it died again instantly.

I am afraid I may have hooked some of the tubes up wrong.
I don't know anyone else around here who rides so you help is greatly appreciated.
Please read the comments above each photograph.

I took some photographs so it would be easier to show where I think I messed up.

In the first photo you can see the valves better since the carburetor is removed.

The two outside arrows pointing to the yellow plastic valves are also going nowhere!
I don't think they ever had anything on them. Do you know?

In the second photo I have one of the tubes off the reserve side of the petcock going to a valve on top of the second carburetor.
I feel that this may be wrong. Do you know?
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TLRam1
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Re: I need help! GT380 dies when I give it any gas.

Post by TLRam1 »

Here are my GT380 carbs, they may be of some help.


Image

Image

Image
Terry

Maybe poker's not your game, Ike. I know! Let's have a spelling contest~

74 Suzuki GT750 / 74 Suzuki T500 / 75 Suzuki GT380 / 97 & 01 Honda Magna / 03 Kawasaki KX250 / 01 Yamaha WR250F / 03 Yamaha TTR 125L
digitalintrospect
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Joined: Tue Jan 31, 2012 3:50 pm

Re: I need help! GT380 dies when I give it any gas.

Post by digitalintrospect »

Thank you. Your photographs do help.

I drew arrows on your photographs and lettered them
a,b,c, d, and e

I do realize from your photos that I had D and E hooked up wrong.
I actually had a hose running from D into E. So thanks for that.

Could you or anyone tell me where those hoses hook up at on the bike?
I am not certain where to hook up hoses A, B, C, or D.

Thanks again. I really appreciate it. I can't wait to get this bike up and running.
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Craig380
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Re: I need help! GT380 dies when I give it any gas.

Post by Craig380 »

The tubes B, C, D & E are simply breather tubes / overflows and just vent to atmosphere.

Tube A is the vacuum pipe that connects to the smaller brass tube on your petcock / fuel tap, to actuate the vacuum diaphragm in the tap ... that MUST be connected or a) the fuel tap will not flow unless on the 'prime' setting and b) it will run fatally weak.
1976 GT380 - wounded by me, and sold on
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
2017 SV650 AL7 - naked and unashamed
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Coyote
Moto GP
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Suzuki 2-Strokes: GT550x2, GT750, GS1000
Location: Tulsa, Oklahoma

Re: I need help! GT380 dies when I give it any gas.

Post by Coyote »

The tubes B, C, D & E are simply breather tubes / overflows and just vent to atmosphere.
And those tubes are not necessary. Tube 'A' on the other hand is important if the petcock is the original. I only have 4 tubes coming off the carbs on my 550 which are very similar. I have 'A' going to the petcock and 3 float bowl overflow tubes.
If you decide not to use tubes B,C,D and E, do not and I repeat do NOT cap them off. If for some reason the petcock has been changed and there is no place to hook up line A, that line should be removed and capped off at the center carb. Optionally, you can just plug the line. By all means do not leave line A open to the atmosphere. You will have a massive air leak and the bike will never run right.
I was born with nothing and still have most of it left.

.
1978 GS1000C
1976 GT550 ongoing money pit.
digitalintrospect
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Re: I need help! GT380 dies when I give it any gas.

Post by digitalintrospect »

Wow, I would have never thought that 4 out of 5 of those hoses we're vents.
I appreciate you both breaking that down for another clueless newbie.
This forum has been a great deal of help. Cheers!
Craig380
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Re: I need help! GT380 dies when I give it any gas.

Post by Craig380 »

As Coyote says, they may be vents BUT don't block them off, atmospheric pressure in those vents is what enables the fuel to flow ... if the vents get blocked then the carb jets cannot flow fuel!
1976 GT380 - wounded by me, and sold on
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
2017 SV650 AL7 - naked and unashamed
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carson shmarson
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Suzuki 2-Strokes: 1972 suzuki gt550, 92 gsx600 f donor bike
Location: Modesto, Ca.

Re: I need help! GT380 dies when I give it any gas.

Post by carson shmarson »

I have been trying to get the carb jets right, and I plugged off all of the above houses to clean up the carb messy look. Hopefully it will fix my pullout jet adjustment, uncapping b,c,d,and e. Thanks guys. I do have A capped off still
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