Hi c3h8
Can you explain the idle solenoid /idle circuit operation on the type d vialle reg.
When is it on when is it off can its operation be manipulated in the software etc.
Thanks again
Vialle idle solenoid
Re: Vialle idle solenoid
This description applies to a standard Vialle system without Electronic fuel control. There are small variations in the regulator function on Electronically controlled systems. Electronically controlled products may substitute there own controllers to activate the main lock off and idle solenoid.
Vialle regulators are two stage regulators. They are comprised of a primary stage where a primary valve/seat receives tank pressure and reduces the pressure to 5 PSI. The primary section also changes the liquid to vapour. The primary pressure flows through a maze to the secondary valve which is normally closed. The secondary valve is held closed by a spring calibrated to keep it closed against the 5 PSI pressure. The secondary valve will open once enough vacuum is generated by the venturri located in the air intake hose or on top of a carburetor.
At idle the venturii does not normally generate enough vacuum to open the secondary valve. A second circuit, idle circuit, is routed from the primary side of the regulator and flows through the primer/idle solenoid and then past the idle adjustment screw to bypass the secondary valve. Idle fuel is at 5 PSI with flow controlled by the idle adjustment screw. Idle fuel is dumped into the secondary side of the regulator and out the vapour outlet.
The primer/idle solenoid is controlled by an electronic module. The module has two functions. It acts as a primer. In the primer function turning the ignition key on activates the module which in turn activates the main lock off and the primer/idle solenoid. The solenoids are kept activated for 2 seconds unless the key is cycled to the crank position. The modules second function is to sense RPM. The module is attached to coil negative and the modules computer chip can sense RPM. Once the engine is cranked the module turns both solenoids on and keeps them on as long as the engine is running. If the engine stops running for any reason (engine stalls) the module shuts the solenoids off. Cycling the key on and off would act just like a carburetor being pumped on a gasoline engine. The 2 second prime time is fixed and not adjustable.
An example would be the driver turns the key on to listen to the radio but does not start the vehicle. The module would activate the solenoids for two seconds and then shut them off. The solenoids would only be activated if the engine is cranked over or the key is cycled again for some reason.
There is a second passage running off the idle passage after the solenoid that routes a small amount of fuel through a .032 orifice. This orifice blows fuel across the face of the sensitive diaphragm under the front cover. Its main function is to create a slight function across the face of the diaphragm to aid transition from idle to acceleration. Because the vacuum generated by the venturii is weak at low RPM some assistance is required by the orifice described to eliminate any hesitation that could occur as the secondary valve begins to be pulled open.
The regulator also has a balance adjuster on it. It is the skinny brass adjustment beside the idle adjustment. The balance adjustment compensates for the pulsing that takes place as air enters the engine. This pulsing, mostly predominant on smaller four cylinder engines, can cause the sensitive diaphragm in the regulator to pulse causing erratic idling. The balance adjuster pushes a piston internally in the regulator to close the secondary passage and prevent the pulse from impacting so severely on the sensitive diaphragm. This adjustment can be used on any engine but typically it is not required on larger V* engines with fairly smooth air flow compared to 4 and 6 cylinder engines. It is also beneficial on older engines that are beginning to wear and experiencing erratic air flow due to valve wear, etc.
Vialle regulators are two stage regulators. They are comprised of a primary stage where a primary valve/seat receives tank pressure and reduces the pressure to 5 PSI. The primary section also changes the liquid to vapour. The primary pressure flows through a maze to the secondary valve which is normally closed. The secondary valve is held closed by a spring calibrated to keep it closed against the 5 PSI pressure. The secondary valve will open once enough vacuum is generated by the venturri located in the air intake hose or on top of a carburetor.
At idle the venturii does not normally generate enough vacuum to open the secondary valve. A second circuit, idle circuit, is routed from the primary side of the regulator and flows through the primer/idle solenoid and then past the idle adjustment screw to bypass the secondary valve. Idle fuel is at 5 PSI with flow controlled by the idle adjustment screw. Idle fuel is dumped into the secondary side of the regulator and out the vapour outlet.
The primer/idle solenoid is controlled by an electronic module. The module has two functions. It acts as a primer. In the primer function turning the ignition key on activates the module which in turn activates the main lock off and the primer/idle solenoid. The solenoids are kept activated for 2 seconds unless the key is cycled to the crank position. The modules second function is to sense RPM. The module is attached to coil negative and the modules computer chip can sense RPM. Once the engine is cranked the module turns both solenoids on and keeps them on as long as the engine is running. If the engine stops running for any reason (engine stalls) the module shuts the solenoids off. Cycling the key on and off would act just like a carburetor being pumped on a gasoline engine. The 2 second prime time is fixed and not adjustable.
An example would be the driver turns the key on to listen to the radio but does not start the vehicle. The module would activate the solenoids for two seconds and then shut them off. The solenoids would only be activated if the engine is cranked over or the key is cycled again for some reason.
There is a second passage running off the idle passage after the solenoid that routes a small amount of fuel through a .032 orifice. This orifice blows fuel across the face of the sensitive diaphragm under the front cover. Its main function is to create a slight function across the face of the diaphragm to aid transition from idle to acceleration. Because the vacuum generated by the venturii is weak at low RPM some assistance is required by the orifice described to eliminate any hesitation that could occur as the secondary valve begins to be pulled open.
The regulator also has a balance adjuster on it. It is the skinny brass adjustment beside the idle adjustment. The balance adjustment compensates for the pulsing that takes place as air enters the engine. This pulsing, mostly predominant on smaller four cylinder engines, can cause the sensitive diaphragm in the regulator to pulse causing erratic idling. The balance adjuster pushes a piston internally in the regulator to close the secondary passage and prevent the pulse from impacting so severely on the sensitive diaphragm. This adjustment can be used on any engine but typically it is not required on larger V* engines with fairly smooth air flow compared to 4 and 6 cylinder engines. It is also beneficial on older engines that are beginning to wear and experiencing erratic air flow due to valve wear, etc.
Re: Vialle idle solenoid
Does the idle solenoid shut off when throttle is applied say , past 1000rpm
Re: Vialle idle solenoid
No. The primer or idle coil remains on all the time the engine is running. If it shuts off there are several faults to look for. A faulty module if equipped. On your ECO system it receives power from the ECO FMS and there could be an issue there.
On a Vialle electronic module the RPM signal might be failing due to faulty wiring, corrosion, etc.
Poor ground connections. Check them all carefully. It was common to ground the solenoid coils to the regulator backing plate. The plate is powder coated and although the coating is scraped off at the ground source it still had to connect to the fender through the plate. It is better to ground the coils either directly to battery or to a good body ground. I believe on the FMS system the coils are grounded through the FMS so it might not be a concern on your unit. Check your FMS ground for a good connection though.
Faulty primer coil. Very important to check as the coils can cause an overload on the FMS and burn out a circuit on the board. It depends on whether the coils are wired through a relay or directly to the FMS. A relay is the safest.
On a Vialle electronic module the RPM signal might be failing due to faulty wiring, corrosion, etc.
Poor ground connections. Check them all carefully. It was common to ground the solenoid coils to the regulator backing plate. The plate is powder coated and although the coating is scraped off at the ground source it still had to connect to the fender through the plate. It is better to ground the coils either directly to battery or to a good body ground. I believe on the FMS system the coils are grounded through the FMS so it might not be a concern on your unit. Check your FMS ground for a good connection though.
Faulty primer coil. Very important to check as the coils can cause an overload on the FMS and burn out a circuit on the board. It depends on whether the coils are wired through a relay or directly to the FMS. A relay is the safest.