Very interesting they did an "exact copy" of the Ellison now per their website. They say on the website there was no vapor lock issues with their Mk1. I know of least two around here that has had it on more than one occasion. Simply, the separate regulator did not benefit from the cooling of the throttle body while air is passing through. Cooling air or a blast tube is needed to keep it operating properly. That is why they copied the Ellison exactly.
While the idea of the built in "primer" and vapor lock release looks like a good idea, I would caution against it. Think about this...the primer is a lever or button that presses on the diaphragm to allow fuel to flow, or release any trapped air from the vapor lock. Depending on your installation, the fuel may not stay in the carb. But that is a completely separate issue. There are others I won't get into as well. Ideally a primer will send fuel directly into the intake near the head or valves for best efficiency, and separately from your fuel delivery system. The least amount of failure points as possible should be the goal with fuel delivery. A quick look at the NTSB reports reveal a high number of accidents are fuel related. With the type of fuel delivery system on the Ellison and Rotec, the pressure on the diaphragm opens the fuel inlet valve which allows the fuel to flow. With their design you have a penetration through the pressure side of the chamber, which requires some type of seal to maintain the pressure for the opening of the valve. If that seal seeps or fails, you lose the pressure required to provide fuel flow. Not a good thing in flight. Granted, they make a good looking product. But in my opinion, this primer idea is an accident waiting to happen. All the new EFS carbs will be CNC'd with some enhancements. The cost will not be as much as in the past but more than the Rotec. We are making most parts in house but for others it just does not make sense to purchase a several thousand dollar multi axis CNC, especially when we are in the meca of commercial and military aviation here in Southern California. The reason they have one in house is from their engine facility. There is nowhere near enough margin in these to justify the expense for just the carb manufacturing. Steve Glover
