Does it matter whether the pulse port is up or down?
I have a 25cc Homelite blower motor with a Walbro carb. It has a primer bulb "on top" and the fuel pump cover is facing down. So the pulse port in the carb body lines up with the port in the heat dam.
That part between the carb and cylinder - I've heard it referred to as "isolator", "insulator", "heat dam", "manifold", "block thingy", etc... My Homelite manual call it heat dam.
Everything works fine, and in this position the choke lever and mixture screws face out (away from the motor shaft), away from the mounting plate and tire.
Now I'm doing another build with a 28cc McCulloch from weed wacker. It has a different Walbro carb. It has the fuel pump cover facing up (primer bulb is external; not attached to carb). The choke lever faces out, but the mixture screws are in, towards the drive shaft. When this is bolted to a mounting plate and put on a bike, the carb screws will be very hard to get at.
So I would like to flip the carb over (rotate 180). The heat dam can't be flipped because the port in the heat dam has to line up with the port in the cylinder. But the heat dam has a semi-circular groove running from the pulse port. I'm assuming this allows the carb to be installed with the pump or diaphram either up or down. Is this correct?
I know that a diaphram-type carb can operate "upside-down", like in an RC airplane flying upside-down. That's all I can find when trying to google my question.
The attached image of the heat dam is blurry, but you can see the port on the bottom and the circular groove. Can the carb be put on with the diaphram side up or down?
I have a 25cc Homelite blower motor with a Walbro carb. It has a primer bulb "on top" and the fuel pump cover is facing down. So the pulse port in the carb body lines up with the port in the heat dam.
That part between the carb and cylinder - I've heard it referred to as "isolator", "insulator", "heat dam", "manifold", "block thingy", etc... My Homelite manual call it heat dam.
Everything works fine, and in this position the choke lever and mixture screws face out (away from the motor shaft), away from the mounting plate and tire.
Now I'm doing another build with a 28cc McCulloch from weed wacker. It has a different Walbro carb. It has the fuel pump cover facing up (primer bulb is external; not attached to carb). The choke lever faces out, but the mixture screws are in, towards the drive shaft. When this is bolted to a mounting plate and put on a bike, the carb screws will be very hard to get at.
So I would like to flip the carb over (rotate 180). The heat dam can't be flipped because the port in the heat dam has to line up with the port in the cylinder. But the heat dam has a semi-circular groove running from the pulse port. I'm assuming this allows the carb to be installed with the pump or diaphram either up or down. Is this correct?
I know that a diaphram-type carb can operate "upside-down", like in an RC airplane flying upside-down. That's all I can find when trying to google my question.
The attached image of the heat dam is blurry, but you can see the port on the bottom and the circular groove. Can the carb be put on with the diaphram side up or down?
