Dellorto float nut gasket leak. What's the trick?
Posted: Tue Jul 19, 2011 4:30 pm
I was installing new floats on my Dellortos last night. The old ones had gotten heavy and had actually stuck in position in the past. I usually reuse the ring shaped gasket that goes on the bolt that holds the float on. I've had a problem in the past where the new gaskets always leak while the old gaskets won't, so I've kept on using the old gasket ring.
Last night one of the old gaskets stuck to the float and was damaged when I removed the nut. I had several new spares, so "no problem" right...? Wrong...there was a puddle of gas under the bike this morning.
Is there something I'm supposed to do to the new gasket to prevent this? Is there a trick other than using a sealer?
On a side note. I tried to use the two methods to adjust float level. The 18mm measurment technique http://www.ducatimeccanica.com/float_levels.html
and Sno Bum's 55cc (ml) per bowl trick. "It is a good idea to check the float adjustment (3.2.2). Here is another method: With the carbs full of fuel, shut off the fuel and clamp the line above the carb. Place a measuring cup under the bowl, and undo the center nut, and let all the fuel run into the cup. It should be 55 cc. Adjust the float if need be, taking this measurement several times, to be sure you are doing it accurately. Officially, from the manual, the float heights are 18 mm, +- 0.5 mm. You will prefer my 55 cc method; or, check the measurement on the workbench."
When I adjusted the carbs the first way I ended up with the floats being just about parallel with the base (like a Bing). But, when I measured the fuel in the bowl (just for curiosity sakes) I ended up with almost 65ml of fuel (that's with all hoses disconected, and just measuring the fuel that trickles out around the loosened bolt). When I tried to go by just the cc's like Bum did, the float had to hang down to 19+mm's and I still couldn't get less than 60cc's. The tang could not be bent any further. I have the latest version of the PHM carbs. Do they have larger bowls?
Last night one of the old gaskets stuck to the float and was damaged when I removed the nut. I had several new spares, so "no problem" right...? Wrong...there was a puddle of gas under the bike this morning.
Is there something I'm supposed to do to the new gasket to prevent this? Is there a trick other than using a sealer?
On a side note. I tried to use the two methods to adjust float level. The 18mm measurment technique http://www.ducatimeccanica.com/float_levels.html
and Sno Bum's 55cc (ml) per bowl trick. "It is a good idea to check the float adjustment (3.2.2). Here is another method: With the carbs full of fuel, shut off the fuel and clamp the line above the carb. Place a measuring cup under the bowl, and undo the center nut, and let all the fuel run into the cup. It should be 55 cc. Adjust the float if need be, taking this measurement several times, to be sure you are doing it accurately. Officially, from the manual, the float heights are 18 mm, +- 0.5 mm. You will prefer my 55 cc method; or, check the measurement on the workbench."
When I adjusted the carbs the first way I ended up with the floats being just about parallel with the base (like a Bing). But, when I measured the fuel in the bowl (just for curiosity sakes) I ended up with almost 65ml of fuel (that's with all hoses disconected, and just measuring the fuel that trickles out around the loosened bolt). When I tried to go by just the cc's like Bum did, the float had to hang down to 19+mm's and I still couldn't get less than 60cc's. The tang could not be bent any further. I have the latest version of the PHM carbs. Do they have larger bowls?