1972 capri gt v6 3ltr

[capri 72 gt]

Hi Guys , I am having trouble with fuel vaporisation after running car. Engine starts first go when cold but after a run and switched off I have trouble restarting with occasional backfire from carb [weber 40dfav] you can actually hear fuel boiling in carb float bowl .car is fitted with electric fan and is not overheating ,motor runs very well ,timing is ok .run 98 octane with valvesaver.Have noticed that a lot of heat builds up under bonnet ,have thought about cutting vents in bonnet but reluctant to deface perfect bonnet .Any ideas .cheers

[allanv6gt]

I have exactly the same confiugration but have had zero problems with fuel vaporisation....even in high 35+ deg heat (inland and dry). I'm still running the original mechanical ffuel pump. About all I can suggest is turning your elec. fan cooler to trigger startup sooner when you stop.
Apologies not much help I'm afarid.

In fact, my other pommie brand-T classic doesn't like anything approaching 30deg , with twin Zenith Stromberg CD175s sitting in the V of the engine and getting vapour lock.

[caprispecial]

Ceramic coated headers lower under bonnet temperatures significantly. You can get the existing ones done for a reasonable price.
Electric fuel pump usualy solves this problem as it quickly fills the bowl at cranking speed.
Make sure there is a thick fibre spacer between the carb and manifold.

[capri 72 gt]

hey allan, cheers for the reply .car doesn't vaporise whilst its running but only when it stops. I have fan override switch which I turn on when stopping , it helps but doesn't eliminate problem . it seems heat sink of motor and extractors can't escape engine bay .thermostat and fan switch are 82 degrees F and all runs perfectly whilst moving no matter how hard its driven .cheers

[vdo]

Ensure that your fuel lines are located as far as practicable from heat sources like exhaust etc to avoid heat transfer. Also you should wrap the fuel lines in heat shield tape.

[capri 72 gt]

Thanks guys, it appears that after going over everything that it's not a fuel problem at all ,thou I will still insulate fuel lines , It appears that when I purchased a electronic hall sensor and new coil they supplied a ballast resistor coil and as car when purchased was a body only when it was rewired the coil was fitted without a ballast resistor causing it to overheat when switched off after running up to operating temp and then it wouldn't restart until it cooled down .I'm looking at replacing it with an electronic coil 12 vt coil so hopefully that fixes problem . I keep you posted Cheers