At the bottom of the fuel bowl under the primary jets is a elongated cap that directs fuel from the jets to the feed tubes to the primary venturis. It is epoxied to the bottom of the bowl.

The feed tubes are cast into the top aluminum body and between the bowl and the feed tubes are "X" rings. Orings with a cross section of an X.

I have found that most often the o-ring (x-ring) goes bad. However the epoxy is known to leak too.

If you remove the top and the o-rings are shot, a simple rebuild will fix it. If the o-rings look good then rebuild it and put fresh epoxy around the elongated cap under the bowl. It will need to fit in the well of the base so don't go crazy. I do not know of a good type of epoxy but there are many fuel tank epoxies that may work. Hopefully someone will chime in with a good brand.

The first two Thermoquads I have rebuild I over tightened the top and crushed the X-rings. DO NOT OVER TIGHTEN THE TOP. Gentle gentle gentle. You can always snug it a little more later if it leaks out the sides of the top when cornering but you can not buy those X-rings with out the $35 kit. If anyone knows where to get them individually I would love to know.

Or you can send it to Scott and have a perfect one returned.