3.5 V8 - Thermostat Bypass and LPG

[101RRS]

On earlier 3.5s the heater hose runs from the back of the engine to the heater and back to the engine via the lower radiator hose. The installer of my LPG decided to provide coolant to the LPG via this pipe so that if you turned off the heater, water to the LPG was also turned off. I have inserted a bypass hose around the heater with a small tap in it to regulate water through the heater. In winter I have the bypass closed so all coolant runs through the heater as the heater is on all the time. In summer the opposite with no water going to the heater and all water going through the bypass. But you can get caught out if there is a hot day in winter or a cold day in summer. If I have water going through the bypass and the heater the heater just gets warm.

Over the next week I will be replacing the water pump and at the same time also replace the thermostat bypass hose at the back of the water pump.

I got thinking :o.

Why not run the coolant for the LPG from the the front of the inlet manifold where the bypass hose connects - to the LPG system and then back to the rear of the water pump. Will there be enough coolant to run the LPG?

If this is possible I can do away with the heater bypass and just use the heater as normal.

Any thoughts?

Garry

[bee utey]

The bypass hose flow is important for keeping your engine temperature even before the thermostat opens. As such I would be reluctant to reduce its flow by installing the converter in this hose. The flow required by the lpg converter is quite small and can be supplied by a 10mm hose nipple tapped into the back of the thermostat housing, the returned to the rad tank. Many D1's are plumbed this way.

The pic shows a Holden heater tap that allows you to put the LPG in line with a heater. When the tap closes (with vacuum applied) it shunts the water away from the heater circuit and allows the lpg to keep running. About $30 and could probably be converted to cable if you can't find a vacuum solenoid to drive it.

[101RRS]

OK - bad idea - thanks for that - might stay with what I have.

Cheers

Garry