Thanks guys, no gunk as I cleaned out carb body. Carb body seems fine, I can't see any cracks or burrs. The new primer cap has a slight warp, I have checked with a ruler. I guess that some silicone won't hold up to bridge the gap and I'll probably need something like some liquid gasket but I don't want to buy a tube just for this. I have ordered another cap but I just want to get the lawn mowed.
Norm, thanks for the offer but I have 2 family members in hospital so a little restricted at the moment.
