I have both types of carb sync tools. I have used the mercury type for years. The mercury columns are very stable and really easy to read. After time the mercury columns will want to separate, this is caused by mercury loss and/or the columns becoming contaminated. Contamination usually comes from rapid opening and closing the throttle. This also can cause mercury to be ingested into the engine. No harm to the engine, want to sniff the exhaust? :skull: The contamination thing may eventually catch up with the Morgan too, time will tell. The biggest problem with the mercury carb sticks is, well, the mercury. In 49 states it is easy to get replacement mercury, in CA buy the Morgan. It is a also a bit big to manage but there are benefits to that, more later.
The Morgan Carb tool is easy to manage, doesn't care which end is up (mostly), easy to store, fits in the FJR luggage and is pretty cool to look at. If I have spent >$100 for a tool why do I have to cut the tubes and insert the restrictors myself? The stainless steel rods must pulse slightly to prevent sticking. You have to nip bits of the tube to achieve this. Fiddle, fiddle again on a >$100 tool.
This is how they compare in overall size:
This shows the difference in scale size.
It is the difference in scale size and therefore the accuracy that sways me strongly toward the toxic but useful Carb Stick. The Morgan begins with a tiny scale and then needs to have the rods pulse slightly, hey, it's in the manual, RTFM (read the factory manual or something close to that). Each pair of heavy red lines on the Morgan corresponds to one division on the Carb Stick.
Alan
