Strong fuel smell and leak

[Dave4093]

Hello all, I'm Dave from WA i'm very new to this site and still finding my way around this forum. I have a 1996 ST1100 (ex WApol one) I have only had the bike for about 2 weeks so far, I up traded from a Harley and loving riding her.

I have noticed a strong fuel smell coming from the bike and didn't think too much about it as I thought it may be just the bike and where the fuel cap is located.

 The other morning I rode to work forgetting my choke was on, parked up at work and left her there for the day. When I returned that night I started the bike up (then realising I left the choke on) and fuel began to leak out of the bottom of the bike. I shut down the bike and check underneath but the leak stopped.  I started the bike up again and the leak returned, eventually the leak stopped and I rode home.

I noticed near the fuel filter there was fuel and appeared to be weeping and on the way home there was the strong fuel smell.

I was wondering if my fuel cap isn't venting right pressurising the system and leaving the choke on just added to the problem ?

The other day after riding up to the girlfriends place which is a nice 40 min ride to Mundaring. I parked up and the fuel smell was there but also the bike was making a noise like a air cylinder being pressurised (best way to describe the sound) It made this sound about 3 or 4 times then stopped.

I've parked her up until Thursday, unitl I can take off the fairings to see whats going on.

dose anyone have any ideas what the problem could be besides the newbie riding it :)   

[Brock]

Gday Dave.

If the pressurising sound was like a groan, then thats normal for the STs. As for the fuel leak/smell, if the fuel is dripping from one of the drain pipes, then one of the Carbies may have a stuck float.

You shouldnt need to use the choke, I am in Joondalup and very rarely turn it on, only when extremely cold and only til the engine is running.

[alans1100]

if it's not one of the drain hoses then one of the other fuel lines.

items 4, 5, 6, 7 ,8  or 34 http://www.st-1100.com/st1100-parts-fiche-fuel-tank-st1100pt.html more likely to be one of these

Hoses etc under the carbs here http://www.st-1100.com/st1100-parts-fiche-carburettors-st1100pt.html

[Dave4093]

Thanks Brock,

I haven't ridden a bike with a choke for a while and keep forgetting about it. Its reassuring that the noises are normal. I have the workshop manual so I'll check out the carb floats hopefully its a easy fix


Thanks again Dave

[alans1100]

Maybe we can merge these two

http://ozstoc.com/index.php?topic=12225.msg1226746#msg1226746

[alans1100]

Just remembered this

the return fuel line to the vacuum shut off, one end is about 8mm, the other about 10mm, hose is 8mm both ends and splits from the inside, looks good externally, but can leak onto the alternator.

[Dave4093]

Yeah sorry I tried to remove one but it didn't seem to work

[Brock]

Other topic removed, and this one moved to the ST1100 Fuels thread.

I forgot about the fuel vacuum switch, I removed mine ages ago.

Rule one when Fault finding on these bikes, do they easy bits first. Getting the Carbs off and apart and back on again is definitely not easy.

[STeveo]

FIX IT NOW!
Mine smelt of fuel just before it went up in flames, but it was completely burnt so I cannot guess as to why, but fix it now please before anything happens.

[Biggles]

FIX IT NOW!
Mine smelt of fuel just before it went up in flames, but it was completely burnt so I cannot guess as to why, but fix it now please before anything happens.

Ooh yes- I remembered that in this present context.  Sourcing every fuel smell is vital since we never did find out the cause of the ignition in that case.

[Dave4093]

Hi all I think I found the problem. My fuel petcock was pouring out fuel. Is it better to buy the kit for one or a whole new petcock?  Or on the other hand is it needed? Can I bypass it?

Any suggestions

Thanks Dave

[Brock]

Bypas it, its easy to do, and I think fairly obvious. I did it ages ago, and removed the Vacuum switch altogether. Dont forget to put a good sized plug in the vacuum line.

[gerd]

Hope you sorted your problem Dave.

I had the same issue in October 2000. Smell of fuel and bike was using a lot of fuel.

Traced the leaking fuel to the fuel tap/cock. Replaced the fuel cock.

Found there was a small hole in the rubber diaphragm on the old one.

Figured 20 years is a good run so replacing with a new genuine Honda part worth the investment.

Has been running perfectly and very economically since.

regards

Gerd