GQ TB42EFI Dual Fuel will no longer start on LPG when cold or left overnight

[mudnut]

Thanks mudnut. That happened to me once years back with low coolant so since then I check and renew it and never been an issue.
I can't figure out the install I have but it's been like that for years and never had an issue till now.
You can see the water/coolant hose in the pic and that's all fine also.

If all the easy stuff checks out, maybe undo a hose and see that the coolant is actually flowing when the engine is first started. Could be a blockage or thermostat problem.