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Hi. I am trying to figure out the wiring for the Dynon sensors on my Gen 4 Jabiru 3300. I am not familiar with the engine, I have always had Lycoming or Continental.
I have been trying to figure out where to plumb the Dynon MAP (manifold air pressure) sensor and which wires from the EMS Dynon wants me to use. In slogging through Dynons 500+ page manual, they call out map sensor wires from the EMS for Continental, Lycoming, Rotax, but not for the Jabiru 3300. Are there no map sensor options for the Jabiru? Where on the motor do you pick up the vacuum?
My engine manual states I have a “not a Bing” carb, but it doesn’t say what make the new carb is. I am not sure if the barb coming out the bottom of the carb is for a map sensor, or if it’s just an overflow…
Has anyone used a map sensor with the Jabiru/Dynon combo?
Typically that barb on the carburetor connects back to the air box as a balance pressure to adjust the carburetor for changes in altitude. If you have not found it yet the Jabiru engine installation manuals are here Jabiru Manuals
Thanks, but on my “ not a bing” carb the balance tube is built into a (what appears to be 3D printed) piece “Cobra Head” that goes to the intake. I am talking about a barb that comes out of the bottom of the carb in the back.
In the attached photo the balance tube, I believe, is the blue hose. The barb I’m talking about is barely visible in the lower left corner. It comes out downward, out of the left side of the carb. None of the carb pictures in the manual shows it. It might just be an overflow, but I’m not sure. There is no info on it.
At any rate, I’m still trying to figure out where to connect the vacuum tube for the Dynon map sensor…
John Austin can help with the link, but the Jabiru online community has said that the new carburetor is a Mikuni PD42J carb if that helps, not certain if this is correct, but it might help you find some more information about the carburetor. I did not install a manifold pressure gauge, but I have MGL avionics and I opted not to get the MAP option.
Thanks John. I'll see what I can dig up on that carb.
Fred, I currently have one of the new not-a-bing carbs on my gen 1 engine. I had previously installed a manifold vacuum gage on the original bing and my recollection is that I was able to use the same plumbing setup. Which was to use the plugged port that leads to a small hole in the carburetor throat just downstream of the throttle plate. I don't have an photos, but the port is or is very close to the brass tube shown in the picture. Sorry this description is somewhat vague, but it was a while ago. I'll be at the hanger later today and will get a photo.
Thanks, I appreciate that. I will take a look at my carb. A picture of your setup would be super helpful!
Hey Fred, here are a couple pictures of my manifold vacuum gauge connection. You are correct about the proper connection point being the brass barbed fitting in front of the float bowl. I used an automotive fuel hose to adapt from the barbed fitting to an AN fitting on a teflon stainless steel braided hose going on to the gauge. Hope this helps.
Thanks for the pictures. Worth a thousand words. I thought that might be it, but I wasn't sure. I appreciate the help.