Post by ed on Aug 16, 2016 23:10:47 GMT
Hi there,
I'm new to the forum and am wondering whether anyone can help shed some light on the controls and set up of a Dellorto SHBC 18.16 P carburettor (Part No. R0958).
I recently picked up a Piaggio Ape 50 (More of a tricycle than a scooter but it has a scooter engine!) as a non-runner. I have stripped the engine to replace the main crankshaft bearings and oil seals and have also replaced the top end with a 75cc upgrade kit. After the rebuild I ran the engine on the bench and it fired up but seemed to be running quite rich so I thought I would fit the engine and then tune the carb.
My problem is that since fitting the engine back on the Piaggio I cannot seem to get it to fire up as the plug keeps getting fuel fouled. I'm hoping it's just the engine being flooded by the carburettor and nothing more serious, however I don't know what all of the controls on the carburettor do and would be grateful if anyone could help me better understand them.
Here is what I have so far:
The float has no adjustment, however is intact and sits parallel to the carburettor body when turned upside down. The needle valve also moves freely and stops the flow of fuel.
The choke jet is a number 50 which is standard.
The screw next to the idle jet sets idle speed by adjusting the slide position.
What I am unsure of:
The idle jet is a number 42 which is standard, but I don't know whether this jet is adjustable or should be screwed all the way into the carburettor body?
The main jet is a number 80. Looking at the Dellorto website these carbs come with a number 56 jet as standard. I'm not sure why mine is different, perhaps this was a standard setup for the Piaggio, or it was changed by the previous owner. Could this cause the carburettor to flood the engine?
What does the white knob to the side of the carburettor adjust?
Do two stroke oil feed fittings contain a valve? I tried to put a wire through the fitting to clean out any debris however cannot get the wire all the way through the fitting.
What is the purpose of the line on the bottom of the crankcase which returns to the carburettor?
I appreciate any advice you can give me as I haven't been able to find much detail about the setup of this carburettor online.
Cheers,
Ed
I'm new to the forum and am wondering whether anyone can help shed some light on the controls and set up of a Dellorto SHBC 18.16 P carburettor (Part No. R0958).
I recently picked up a Piaggio Ape 50 (More of a tricycle than a scooter but it has a scooter engine!) as a non-runner. I have stripped the engine to replace the main crankshaft bearings and oil seals and have also replaced the top end with a 75cc upgrade kit. After the rebuild I ran the engine on the bench and it fired up but seemed to be running quite rich so I thought I would fit the engine and then tune the carb.
My problem is that since fitting the engine back on the Piaggio I cannot seem to get it to fire up as the plug keeps getting fuel fouled. I'm hoping it's just the engine being flooded by the carburettor and nothing more serious, however I don't know what all of the controls on the carburettor do and would be grateful if anyone could help me better understand them.
Here is what I have so far:
The float has no adjustment, however is intact and sits parallel to the carburettor body when turned upside down. The needle valve also moves freely and stops the flow of fuel.
The choke jet is a number 50 which is standard.
The screw next to the idle jet sets idle speed by adjusting the slide position.
What I am unsure of:
The idle jet is a number 42 which is standard, but I don't know whether this jet is adjustable or should be screwed all the way into the carburettor body?
The main jet is a number 80. Looking at the Dellorto website these carbs come with a number 56 jet as standard. I'm not sure why mine is different, perhaps this was a standard setup for the Piaggio, or it was changed by the previous owner. Could this cause the carburettor to flood the engine?
What does the white knob to the side of the carburettor adjust?
Do two stroke oil feed fittings contain a valve? I tried to put a wire through the fitting to clean out any debris however cannot get the wire all the way through the fitting.
What is the purpose of the line on the bottom of the crankcase which returns to the carburettor?
I appreciate any advice you can give me as I haven't been able to find much detail about the setup of this carburettor online.
Cheers,
Ed