Problems with floats Dell'Orto

sfcrgs

sfcrgs

Senior member
Location
Vend?e (France)
I would like to report a problem we encountered with the new Dell'Orto 36mm, purchased from Dell'Orto UK
On both machines (Renata and 1200), the floats are not waterproof. They are filled with gasoline, shortly after commissioning  :o
Obviously machines walked less ... >:D
At Imola we did a repair glue, but it is not satisfactory to consider Spa with these floats.

If anyone had this problem, can you tell us your solution ?
thank you
Bertrand
 
If the 36mm Dells use the same float as the 32's I'd give OCT a call, because they may have the OEM black 10 gram floats in stock. The new plastic things are WOFTAM IMHO ::)
 
European regulations prohibit ethanol. We drive with normal petrol, but with a high octane.
In these new carburetors, floats are white.
 
I've had a brand new white one leak. It was for a PHBH though so I think it was 11gr.

For a considerable amount of time I tried drying it out by inverting it evey now and then. Didn't ever look like working.  ::)

They leak at the join between the 2 halves.

* Added later to clarify: I stuck the float up on a sunny window sill so it would get warm. My thinking was that the fuel would slowly evaporate and the pressure would allow it to vent then suck in clean air at night. I would invert the float on occasion so that the hole was covered by fuel then alternately air. No success I'm afraid. I knew I could drill or melt a hole in the float and drain it but I just wasn't that keen due to explosive fumes, then try and re-seal. Funny how fuel can evaporate in an opaque fuel bowl, out of the sun and gum up the jets in no time at all.  ::)

Wasn't worth chasing a replacement Drikko. Postage would have been more than the float was worth.  ::) Sometimes the practicalities outweigh the legalities.

Ethanol Clem? No, it is just poor manufacturing. Don't get too paranoid about ethanol. I tip it down my throat with a zest and the only tissue it has a corrosive affect on is my brain cells. I noticed that Listerene, a mouth wash, is 22% ethanol and that comes in a plastic bottle. Must be special plastic!  :D

PS. Liked your piccies of the Bunya Mtns, Drikko. I did a day ride up there the day after ANZAC day. Very pretty, I hadn't been there before.
 
I don't get it, a company sells you something that doesn't work, so scream at them and/or get your money back, you can't sell something that isn't 'fit for purpose'! With the possible exception of Coopers Ale of course....  :o :o
 
Fortunately I'm hoping to avoid these problems - I'll have no floats in my carbs and use a remotely mounted single float bowl - then I can adjust the float height and fuel slope with minimal hassle. -  Was very lucky and got a pair of these bowls from Merlin on this forum - Regards - Phil
 

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Hi Folks,
Have these float problems been addressed?  I am considering buying a set of PHF's new and would like to avoid buying a different set of headaches to those I have now.  Of course I could swap in the 10gr floats from the carbs which will be replaced, but it seems a little silly.
If the 8.5gr floats are indeed fuel-proof (a handy feature in a float), is there a tuning adaption to be made to allow for the lower weight?
Cheers
SteveB
 
phil37 said:
Fortunately I'm hoping to avoid these problems - I'll have no floats in my carbs and use a remotely mounted single float bowl - then I can adjust the float height and fuel slope with minimal hassle. -  Was very lucky and got a pair of these bowls from Merlin on this forum - Regards - Phil
Click to expand...

Interesting idea Phil.  Would love to know how these will get mounted.  Is this a work in progress, or have you tried it yet?  Thanks -- Chris.
 
breganzane said:
Have these float problems been addressed?  

If the 8.5gr floats are indeed fuel-proof (a handy feature in a float), is there a tuning adaption to be made to allow for the lower weight?
Cheers
SteveB
Click to expand...

Hi Steve,

To answer the first question, no, not to my knowledge. To add to my post above they can be sealed. I use good marine epoxy and put a thin run around the join. Similar to what Boba would use. A soldering iron and plastic welding would work too if you were thorough.

I put the new float out in the sun until it is warm then use a long thin pointer to apply a drop of epoxy and run it round the join. If there is a gap then as the temp drops the epoxy should be sucked in. That?s my theory anyway. I leave it for at least a few days. The longer the better really. The weight would be negligible.

As for the difference in floats. I experimented with this a while back as I had different floats on each side due to one float filling. I used what I had until the replacement arrived. What I found is the heavier float actually floated higher. :o   :LOL:

In theory the 8.5 should float higher, shut of the valve sooner and the mixture should be leaner but I?d just do a few plug chops and if it looked OK I?d be happy.
If you do feel like altering the float height/jetting then the bend should be down away from the roof of the bowl so you have room to adjust but my guess is you won?t have to.

If you want to experiment then fuel has  S.G.of about 0.85 and water is 1.0. I just compared the floats in a glass of water pivoting on the edge. The istance from the pivot to the valve is small compared to the floats so the change where it counts is small.

I recently got energetic about getting the fuel out of the float. It is now all out and sealed as a spare. Lots of sun, and rotating it daily did the trick.
Cheers

Rod
 
Hi Chris - I haven't yet fitted the remote float bowl - it's for my 860cc twin - I will mount it with  a rubber mount between it and the frame - I will use 40mm carbs angled up by about 10? - so will have to severely angle them in to clear the fuel tank (and maybe frame) - hence the need for a different float bowl. - I used to use a remote float bowl on my single (TT) carb on my 650 BSA that worked fine. - Will post photos when done - Regards - Phil
 
phil37 said:
Hi Chris - I haven't yet fitted the remote float bowl - it's for my 860cc twin - I will mount it with  a rubber mount between it and the frame - I will use 40mm carbs angled up by about 10? - so will have to severely angle them in to clear the fuel tank (and maybe frame) - hence the need for a different float bowl. - I used to use a remote float bowl on my single (TT) carb on my 650 BSA that worked fine. - Will post photos when done - Regards - Phil
Click to expand...

Phil - a single bowl on twin carbs can often give some weird symptoms. Lean it over and one side goes lean, one rich...ask an Aermacchi owner about running an offset float chamber. G45's are notoriously bad with GP's and a central chamber. There are tricks which can help, feeding the carbs from the opposite side of the chamber, ie feed left carb from RHS of chamber with a loop of hose outside the carb sometimes works. If it's really bad swill pots don't have to be very big...

Classic case is the MV six - it has to be held bolt upright to be fired and around the circuit you can hear every time it's leaned over as cylinders cut out...Matchbox chambers stuck in wherever they can be fitted...ugly to set up.
 
I don't understand how leaning a bike (while in motion) can cause the float level to slosh from side to side. As far as the bike is concerned, gravity is always acting through the centreline of the bike, otherwise you'd be careering off into the scenery. One possibility is if the rider is hanging way off the side like they do in MotoGP, which moves the centre of gravity of the whole plot (bike and rider) off the centreline of the bike. If you don't climb around too much in the corners, a shared remote float bowl should in theory work OK.

I actually have the opposite problem on my Kawasaki with sidecar attached. It doesn't lean over. Vigorous left-hand cornering, or flying the sidecar in the air, with anything less than half a tank of fuel results in fuel starvation. All the fuel sloshes to the right-hand side of the tank, leaving the fuel tap on the left side high and dry. Being fuel injected, it cuts out almost immediately when the pump starts sucking air.
 
Yeah. theory is wonderful...practise is often different.

At the same Pukekohe Classic festival meeting where i saw first hand the MV six's problems I spent the practice day adjusting the float chamber height on an Aermacchi in .005in increments until carburation was acceptable on left and right hand corners...Must have worked, it won 3 races.

The ex works Macchi mechanic looking after the MV came over while I was warming the Macchi up on the dummy grid, leaned it left, then right, slapped the rider on the back, "Bene, bene, ver good" I was just pleased he didn't ask for help with the MV...
 
Thanks for the info Greg - I accept that theory is often trumped by reality - especially with engines! I have already considered swill pots if there's a problem - I'm also lucky enough to have been given two of these bowls - Regards - Phil
 
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