Float Bowl O-Ring

[Diploman]

I'm replacing the float bowl o-ring gaskets on my V50's VHB carbs.  This is a very obvious and simple operation, seemingly, but in execution it is not so simple.  The slender o-ring conforms well to the groove in the float bowl rim, but when stretched fully around the bowl it develops tension which tends to make the o-ring pop out of the groove at corners.  I can't imagine I am the only one who has experienced this frustrating phenomenon: the o-ring that was perfectly seated 10 minutes ago now has popped out of one corner -or two - just when it was about to be re-installed on the carb.

Any tips from the Dellorto whisperers on how to make this devilish o-ring stay put?

I thought about using some Permatex 300 "Form-a-Gasket", but the label says it is good for applications where exposed to "synthetic oils, lubricants or automatic transmission fluids".  No mention of gasoline/petrol, which I conclude must be a solvent that would wash away the Permatex (and maybe block the carb jets).  Perhaps some grease might help the 0-ring to cling to its intended location.- anyone tried this? I searched the WildGuzzi archives and found no mention of any products to help the o-ring adhere, or of anyone noting difficulty in seating the o-ring. So perhaps there is an art to installing it to minimize the tension that makes it want to rise at the corners.   Maybe I just need to know the trick.  As Leadbelly used to say when asked how he played his amazing 12-string rags (eg Fanning Street): "It's just so easy when you know how."  Thanks in advance for help.

[Groover]

Stretch it a little before putting in on, then it will seat without the fight. Just a little over will do, but you still have to be somewhat fast putting the bowl on and put the pressure on. That's how I do it.

[jwinwi]

Also try rolling it towards the outside so when it rolls back it stays in the groove. Always takes me several attempts to get it just right...

[Chuck in Indiana]

Also try rolling it towards the outside so when it rolls back it stays in the groove. Always takes me several attempts to get it just right...

This. The first two corners go easily.. then roll the next two to the outside and fit them in the groove.

[Tom H]

When I've had one that really fights me, I would use just a few strategically placed very small dabs of Permatex #2.

Have fun
Tom

[acguzzi]

yes, its a PIA, sorry thats all I've got

[John A]

on troublesome ones sometimes it helps to run the oring under hot water for a bit

[Antietam Classic Cycle]

I find the o-rings I buy from McMaster-Carr fit better. But, when the Dellorto ones don't fit right, I stretch them.

[Diploman]

Very astute and helpful guidance from the WG braintrust!  I'm sure that, using this advice, I will have my o-ring issue settled very shortly.  Many thanks to all!!

Charlie:  Can you give me the identifying dimensions/descriptions for the o-rings you get from MaC-Carr?  I would like to order from them.  Thanks.