Leaky carbs

[AndyD]

Again thanks everyone
Plenty of things to check when I get away from work today.
I didn't know that the floats were hollow on these so will check them in water.
Also will clean the float valves again just to be sure and the brass pipe for leaks

If all else fails are there any good / bad recommendations on repair parts - eBay has quite a few offering from around the world varying enormously in cost and contents.
On the GS1000s the strong recommendation was never use anything except original due to quality issues - is that the same fro these bikes?

Will update after the next round

Cheers,
Andy

[H2Eric]

This problem sounds very familiar. If you have to replace the float needles and seats use genuine parts, others are pretty dire from my experience. As Julie says check that the floats float and they are all at the same level, mine didn't. I replaced the float needles and floats on my 350F and all is now tickety-boo and leak free. I had a similar problem with brass floats on an H2 which sank i.e. full of holes and full of petrol. Allens Performance came to the rescue with 3 new floats, problem solved and that was long before ethanol problems.

Cheers all

Eric

[taysidedragon]

I bought rebuild kits from David Silver for mine and they work just fine. They are Keyster kits that sometimes get bad reports. Maybe there are fakes on the market so buy from a reputable dealer. 

[AndyD]

Thanks again,
Had another go at the carbs this afternoon
Floats all float and evenly so I think they are OK
Bowls don't leak so guess the brass pipe is OK
Cleaned float valves again (shiniest part of the bike now!)
Checked float heights again
Put back on test and after a few seconds two carbs have a happy trickle from the overflows.
Turning the fuel supply off and then back on again the trickle doesn't reappear, only a drop forming on the overflow pipe.
I'm pretty sure it's worn float valves so I'll order up some replacements and see if that sorts it.
While waiting I might start on a CB900FD I finally hauled out of the shed on a sunny day last week - mind you it's a lot heavier than the 400, especially with seized brakes!!

Cheers,
Andy

[SteveD CB500K0]

FZ.




Sent from my iPhone using Tapatalk

[Laverda Dave]

Andy, have you run the engine since rebuilding the carbs? I (and others) have suffered similar problems after rebuilding the carbs with new valves etc. Try running the engine for a while and the dribbles may stop, they did on mine. Nothing more frustrating than continuing to remove and strip the carbs!

[AndyD]

Oddjob,
I agree the FD is a lovely looking bike and can't wait to get stuck into restoring this one.
Bought it almost 10 years ago from the original owner who'd started replacing the fork seals in the late 80's, given up and left it in the garage ever since.
Pic attached shows her on arrival with just some front end bits missing (all in boxes), second pic shows her now having been pulled from her slumber in a slightly damp shed in my garden so more surface rust than when I bought her.
Paintwork is really good and I've got a new 4-2 exhaust (chrome not black sadly) to go on so hopefully can get her back to pretty original state.
[ Guests cannot view attachments ] [ Guests cannot view attachments ]

Cheers,
Andy

[AndyD]

Thanks Dave,
You may well be right - I haven't put the carbs on at all yet, hoping to make sure they didn't leak before trying to.
Not sure how hard the 400 ones are to get on and off but with other bikes it's been one of the most awkward, annoying and sweary jobs so I hoped (probably hugely optimistically) to get away with doing it once.
I ordered the carb repair kits from DSS last night so will give new float valves a go for starters.
One thing I noticed was that the 4 float pins varied hugely in how springy they were so maybe have had a hard life and are a bit tired.
Cheers,
Andy

[Laverda Dave]

Is that YOUR shed 

[AndyD]

Dave,
'Had' to build the garage a few years ago mainly because the sheds were too full of 'projects' and there was nowhere to keep the shiny finished ones.
Of course as soon as I got more space temptation took over so now the garage is also filling up - and the sheds are still packed!
Luckily have an understanding wife!
Cheers,
Andy

[AndyD]

Good spotting
The XT is a 250, the smaller GS is a 550, the grey one is a GSX1100EZ ( katanas ugly sister) and the red one is a CB1100f
The turbo was a real impulse buy - couldn’t resist it but no idea where to start with it!
Cheers
Andy

[Golfcarmad]

I have just had same problem after complete rebuild.
So I took carbs out-and cleaned everything again meticulously.
In my opinion when springs inside move a little sideways-this causes the issue.
Mine are fine now-just clean them and be gentle putting bowls back on.