Coolant and Fuel System – 2 Hours

Many builders complain that the corrugated coolant hoses are difficult to seal on the short run from the coolant pump to the billet filler. In addition to this needing to be a 90 degree bend, the diameter of the water pump outlet is different to the billet filler.

As the filler should also be the highest point in the cooling system I decided to purchase the Breeze Automotive 1.5” to 1.25” 90 degree elbow (part #70619).

Since build school I have never liked the model plastic coolant expansion tank supplied in the kit, beside it looking cheap (it’s actually from the BMW), it looks to modern. Factory Five have updated this in the new Mk4 kit, this being a stainless steel vintage looking unit (part #15030). This unit mounts on the F panel.



All fuel injection systems require a fuel regulator to main the correct fuel pressure for the injectors, this is placed in the return fuel line, although a pressure gauge is not necessary, it is the easiest way to set the regulated pressure.

As the fuel lines run along the passenger side 4” chassis tube the fuel regulator was mounted on the firewall next to the passenger foot box, the vacuum line was then run to the throttle body.

Other jobs completed today included adding a 2nd temperature sensor, the reason I have two is that each is dedicated to either the temperature gauge or the EFI computer. The main EFI wiring harness was connected to all the injectors, and sensors in the throttle body and inlet manifold.