No fuel

[Guest]

Hello, last week I bought a 1984 GSX750EF, a non runner but it turned over on the button OK and the price was decent so I went for it.

Its basically sat in a damp garage for 10 years and not run at all during that time.

Obviously there is a lot to do but I thought I would at least try and get it to fire up.

Compression is OK (I think) and it sparks on all 4 cylinders but there is not even a hint of it firing on any cylinder. I have filled and drained the carbs twice with fresh petrol via a funnel (they were bone dry with signs of rust in the bowls) and have taken the top off one and the slide was clean and free to move.

I was wondering if this is fairly typical after such a long time? I ask as I remember years ago I bought a gs650 that fired up on 3 cylinders under the same circumstances as only one carb was blocked. I was expecting at least something from the GSX but nothing.

I suppose I'm delaying taking off the carbs for as long as possible ... :-)

[greg78gs750]

no point in delaying....

[fastbysuzuki]

Yes if you want it to run ok time to strip them there is a tutorial Here get new orings including the inlet rubbers orings from http://www.cycleorings.com/#BS_Series_O-ring_Kit

[cowboyup3371]

Take the carbs off, ungang and disassemble each one, then dip them properly for 24 hours each. Don't buy a carb kit but get the orings from Robert Barr as mentioned above. Do the valve adjustment and then go from there.

[OldVet66]

All of the below. I haven't started my bike in over a year because of a knee replacement. Went to start it, no fuel. I disassembled the petcock yesterday and discovered the O-ring on the vacuum diaphragm has stuck. Freed it, coated lightly with dielectric grease, reassembled and the bike fired up immediately. All the other suggestions if they haven't been done, could contribute to the same symptoms. I was extremely lucky. Envisioned, carburetor rebuild, guess StarTron did it's job there.

[Nessism]

There's no point in trying to start the bike if there are signs of rust in the float bowls. Tear down the carbs and fully rebuild them and also attack the source of rust in the fuel tank. There are many threads in the archives here about how to deal with tank rust so you might want to dig around using the search function if you need guidance.

[xtlegend]

Good news, the engine is now up and running after 10 years dormancy!

I partially stripped the carbs - cleaned the float bowls and needle jets and made sure other jets were clear. Expected worse TBH. Unfortunately I cannot remove one of the pilot air screws. One of the others was very stiff but I got it out but this one is no go. It rotates in and out 1/4 turn but no further so that will have to stay as it is.

Anyway I put things back together but still nothing really - maybe the slightest hint of something trying to happen. So I buy a pair of new coils and fit them. The engine ROARED into life blasting my legs with rust due to a big hole in the exhaust! Music to my ears as the engine is mechanically quiet.

Anyway I can only think that the spark was very weak from the old coils - there was definitely HT there though as I got a 'tingle' off one of the leads .....

Now onto the 50 other jobs that need doing!

[tom203]

Sounds promising, so get to the fully Monty carb cleaning,cuz it will never run right without clean passages on ALL four carbs