The primer pressurizes the float chamber with air to force more fuel into the engine , not to force more air into the motor.
I've had a few Victa 18 mowers that only revved when I clamped the snorkel mostly closed creating a choked motor making a richer fuel mix to compensate for air leaking into the motor from worn crank seals.
If it's difficult to get dirt to the pond you could always fill most of the hole with old wood ,like old pallets ,I've heard of people filling holes with wood chips.
I've filled a hole before with half burnt wood and put a little dirt on top.
There's still a few ways to check the seals that won't take much work ,some people fill the crank case up with diesel and when the seals are bad, diesel will leak out past the seal in a day or 2 on the lower seal.
Another way is to start the motor without the blade plate and spray starter fluid at the seal and see if the motor runs different when spraying the seal and some people instead of using starter fluid use oxygen from an oxy acetylene torch.
I've had a few 2 strokes that needed new seals and when I slid a 1 thou feeler gauge between the crankshaft and the seal the feeler gauge had no resistance.
If you still have Victa bases and are after any late model Victa catchers let me know before I throw them out Norm as I have about 20 still here that have been dismantled (in 2 halves) so they can be stacked inside each other (takes up less room) they just clip back together then you put the 2 self tapers back in when you want to use a catcher.
