Dellorto Carb float sinking--a fix

[Chuck in Indiana]

Most epoxies are fuel resistant, but not fuel proof.. ;D

[steamdriven NZ]

When I bought the Nevada donor bike it ran like a pig and leaked fuel when parked (useful bargaining tools though!)
It ran well enough to get it home (3 days ride) and then I started looking.
It had......a white float. Half full of fuel. It had been drilled and repaired with epoxy by persons previous, but hadn't held, as others have found.

I found a replacement float at 11g which I tried to use and just bend the tab to get the level right to run right but I just chased it.....
So on the phone to Eurobike and a proper 9.5g float in in black, factory settings on the carb and...........perfe ct.

ProSeal is very good stuff IF you get the fuel tank sealant they provide as above link (there are many types of ProSeal for different uses) . I think that what that is in the link above will be what we/I know as 1440 and is available in A or B. A is very runny and brushable,  good for forcing into tight gaps BUT B is thicker and not so inclined to run back out again. 1440 used to be 1422 but 1440 is apparently more fuel resistant. (1422 superseded by 1440) The suffix number is the useful pot time once mixed, eg 1/2 or 2 hrs. Once mixed you can freeze it and it will take days to go off so if you have a couple of jobs to do you can a. mix it into small containers and b.freeze and thaw as necessary. Won't last much past 4-5 days though. We use it a lot in the hangar where I work. (Boeing and Airbus products abound).

Ultimately, you will be adding grams to your float which may be able to be adjusted to work. I found that a few grams made all the difference and the new part made life very easy. Your situation/method/view on all this may vary and be just as right as mine.... :)

[Triple Jim]

Most epoxies are not terribly heavier than fuel, so as long as you add it to the outside of the float, only about 1/4 to 1/3 of its weight will contribute to changing the float height.  If you add it to the inside so it can't displace fuel, then all the weight will count.

[Curtis Harper]

Matt,
As per your request, I have a replacement float submerged in gasoline. After the first 24 hours there is absolutely no sign of leakage.

As for where the problem stems, I might ad this: I have sold over 100 of these floats in the last year alone and have not had a single complaint in the quality of the part. I have however seen a stark difference in packaging and handling quality of shipments from various distributors. There is a Dellorto distributor in the US that most shops buy from, that has sent me floats that have been broken upon reciept. The Italian supplier that I use has always sent them properly packaged and they arrive safe.(I no longer use the American Supplier if I don't absolutely have to.) So my point would be this. The problem to me would be more of the handling of the part than the part itself. It is possible for two floats to get shoved together in shipment and deform the shape of each bulb, thus breaking the seam and causing the leak.  The exercise of epoxy may be fruitful, but I believe the wrong cause for the problem is being pursued.

[lucky phil]

 Loctite "wickin" around the seam.
Ciao

[dilligaf]

Matt,
As per your request, I have a replacement float submerged in gasoline. After the first 24 hours there is absolutely no sign of leakage.

As for where the problem stems, I might ad this: I have sold over 100 of these floats in the last year alone and have not had a single complaint in the quality of the part. I have however seen a stark difference in packaging and handling quality of shipments from various distributors. There is a Dellorto distributor in the US that most shops buy from, that has sent me floats that have been broken upon reciept. The Italian supplier that I use has always sent them properly packaged and they arrive safe.(I no longer use the American Supplier if I don't absolutely have to.) So my point would be this. The problem to me would be more of the handling of the part than the part itself. It is possible for two floats to get shoved together in shipment and deform the shape of each bulb, thus breaking the seam and causing the leak.  The exercise of epoxy may be fruitful, but I believe the wrong cause for the problem is being pursued. 

Curtis,
Thank you for humoring me.  I could tell from our phone conversation that this was not a common problem however it is clear from some of the input from this thread folks were having problems with the floats that sounded very much like the problem I was having.  You may very well be right.  After our conversation I reexamined the floats with the old magnifying glass.     The crack is on the seam but the seam (joint) it's self is sound.  This would tend to support your contention that is a handling problem and not one of manufacture.  Thanks again.  :BEER:
Matt  

PS:  The bad floats did not come from Harpers.   ;-T

[dilligaf]

My repaired float has been submerged going on three days now.  ;-T  I coated the crack with Bill Hirsch Gas Tank Sealer that I just happen to have handy.  This is not a two part epoxy system.  I used a heat gun to heat the float in an effort to dry the insides then I cleaned with soap and water. In hind sight I should have roughed up the area with some sandpaper to give the sealer some tooth but so far it hasn't lifted. I called the shop where I purchased the defective floats and was told they had another failure reported to them. Their supplier in located in the US and that very much supports what Curtis posted.  My thanks to all of you and your suggestions.  :bow I've saved the address for some of the sealers recommend and should the Hirsch fail they will be my next attempt.  Thanks again and a special thanks to Curtis.   :+1
Matt 

[Aldo]

As highlighted by others, the white ones seem to be more prone to issues, even when brand new.  Think Curtis Harper has a point, handling between suppliers probably has a play in how they end up, but I always thought the black/brown ones were just better quality overall.

Here's a pic of mine...this float was pulled from a new [yes, new] Dellorto PHF36 carb that I had mounted on my SP. The carbs literally had a less than 1000 miles on them when symptoms began.  Just one side...

[Curtis Harper]

Just had a minute to peek in and was reminded of this thread and the fact that I had the float being drowned in the shop for you. Went and pulled it out. It has been connected to a heavy enough chunk of metal to keep it under gas since Monday. Can see no problems with them at all. Can send them out today. No worries though, they will still smell like fuel so the postal service will flip out, think it's a bomb, send in the robots and will probably put it in a detonation can and explode it. However if they do make it through the system this glorious holiday season, they should serve you well.

[Antietam Classic Cycle]

Here's a pic of mine...this float was pulled from a new [yes, new] Dellorto PHF36 carb that I had mounted on my SP. The carbs literally had a less than 1000 miles on them when symptoms began.  Just one side...

Same here - customer's bike with new PHFs installed just a year before, both floats had gas inside them. Chucked them and installed a pair of NOS grey ones.



I doubt Dellorto is damaging them at the factory.

[Curtis Harper]

All I know is that of all the parts I have sent out, no one has complained about this problem. Of all the epidemics that seem to happen to all of these bikes, I just watch the parts sales and see how many pieces I sell per each subject and if the quantity rises dramatically, I take time to look at it and see what is up. If there is a rising issue, it may be worthy of noting.

As for this part, I sell so many of these white floats due to the fuel being so different than back in the 70's. The grey floats are usually 14.5 grams some are 10 gram and are not as buoyant as need be for today's fuels, thus not pushing against the needle enough to stop the flow of fuel. The white ones are 8.5gram and float mush better causing a better push on the needle.

[Curtis Harper]

Aldo, can you see on yours where the leak is?

[dilligaf]

Both of my defective floats had a 3/8 inch crack in the seam on the same float in the same spot.  The seams are sound.  I have no idea what caused the crack in the two I have.  Both came from the same source in the US and  I think stress caused by improper handling is as good a call as any.  Who knows?   Less face it, defects are being reported from all over the world.  What we do know is that fuel is getting into the floats.  What we don't know is if it for the same reason.  What I do know is that I'm going to be very slow to mess with the carburetors on the SP.  :BEER:
Matt    

[dilligaf]

As highlighted by others, the white ones seem to be more prone to issues, even when brand new.  Think Curtis Harper has a point, handling between suppliers probably has a play in how they end up, but I always thought the black/brown ones were just better quality overall.

Here's a pic of mine...this float was pulled from a new [yes, new] Dellorto PHF36 carb that I had mounted on my SP. The carbs literally had a less than 1000 miles on them when symptoms began.  Just one side...

As best I can tell it's the same side.  On mine the crack is in the seam just above where the two bars attach the float to the hinge.  I've got a 6 pack of  :BEER: that says it the same defect.  ;D  :BEER:
Matt

[dilligaf]

Well my repaired float lasted just a few days over six months and 1200+ miles.  Trashed the "repaired" float and replace it with the one Curtis sent.  That one didn't quite last a month but it do go 776 miles.  Most likely it would have lasted longer as the motorcycle was running OK but, as I wanted to ride it to the VA Rally this coming weekend I pulled the float bowls just to check.  Right OK, left starting to full with gas. This is really starting to  ::( me off.  So far I can not find where this one is leaking.  The last two were easy and no problem getting the gas out. You'll have provided plenty of ideas.  One of them is going to work.  ;-T Just going to take awhile.   :BEER:
Matt

[dilligaf]

Found the spot. Same as the other two.  I read the post about Seal All and thought I would give it a try.  Looks like the fuel tank sealer I used previously only in a tube.  That repair lasted 6 months.  I suspect the only lasting repair is going to be the two part fuel tank sealer many of you recommended.  Buying new floats is like a C R A P shoot and right now I am 3 for 4.  Not good.  Anyway, the LeMans is running and it's going to the VA Rally with a spare float in the tool kit.  ;-T With my luck, I'll drop and lose the needle while changing the float.   :BEER:
Matt

[dilligaf]

Well, so far-so good.  Pulled the float bowl to check and no gas in the floats.  The ride to the VA rally and back produced some of the best gas millage I have ever gotten on this motorcycle.  Could be something to the white floats being lighter than the gray ones.  Now to come up with a permanent fix. Lots of good idea on the board and I'm sure one will work.  Meantime, I'll continue to carry a spare float. :BEER:
Matt

[dilligaf]

From my post from 12/12/2013:
"I coated the crack with Bill Hirsch Gas Tank Sealer that I just happen to have handy"
This is not a two part system and as of 03/04/2015 is still working.   ;-T
Matt

[Kiwi_Roy]

Just a thought, how about cutting one end off the damaged floats and inserting a cork, I seem to recall a lot of old cars had cork floats on the fuel level sensors.
Cut the cork into the approximate dimensions then boil them for a few minutes they become soft and will distort to fill the cavity.

We used to boil the corks for inserting into the old Brit bike clutch plates.

[Muzz]

We used to boil the corks for inserting into the old Brit bike clutch plates.

O man, that brings back memories!  ::)  Had to do that at a party once to get the old Matchy (slowly) back home. :D

[Kiwi_Roy]

Bump