In light of all the recent issues over alcohol in modern motor fuel and hot carburetor problems, this is a fairly cheap idea brought to a test by Lindsay Sampford in Cambridgeshire, UK.

"Well, I have got my fresh air duct fan fitted and it blows a gale into the engine compartment! The drought can be felt right back at the left hand firewall, and when I close the bonnet, air can be felt escaping at both vents but more so at the left hand vent. The fan is quite noisy but if it keeps the engine sweet when I am in a hot jam I will be happy with that. I have wired it to the fog light switch so that I can run it when I need it". -- Lindsay

Find more information about 4-inch and 3-inch bilge blowers in the Accessories section. Lindsay says the noise level may be a bit annoying, but I haven't heard it in person. It also strikes me that while a computer box fan might be a little shy on air flow, this 125-230 CFM bilge blower may have significantly more flow than is needed to simply blow a little cooling air on the carburetors. This blower was originally recommended for use in the heater duct to blow ample cooling air on the passengers' feet in hot weather, to assist with demisting in humid weather, and to assist with heating and defrosting in winter.

As the next trial, I would like to see one of the 3-inch bilge blowers with the legs cut off to be installed inside the 4-inch steel vent along side the radiator cowling. This would virtually disappear from site leaving the front vent hose as original, and not occupying any other service space. At 100 CFM air flow with duct work, the 3-inch bilge blower may still be a nice assist for the heater, ventilator and demisting system. I can imagine twin blowers out of sight, out of mind, until the moment they may be needed, in which case a little noise may be welcome. Adding a few amps of electrical load here and there ultimately adds up to more power than the original generator was intended to supply. Those of us who have already installed an alternator, we can now fiddle with these extra electrical gadgets at will.

On 27 May 2012, Ed Bell in Oregon, USA wrote:
"I installed a 4 inch Atwood bilge blower by cutting the consertina duct and installing the fan in the middle of it. I cut the feet off of the fan, and split the ducting in several places for about an inch to allow it to expand around the ends of the fan body. I used two 4 inch hose clamps to hold the ducting to the fan. After painting the fan black, it is not noticable unless you are looking for it.

On 27 June 2012m C Vassallo in Malta wrote:
"I have fitted a marine 4 inch blower and found it to be very effective from the amount of forced air emitted through the vents on the side of the bonnet. I have sanded down the moulded parts on the outside of the unit to make it round like the pipe and sprayed it black both outside and inside. I fitted a short length of pipe on the front edge to make the unit less conspicuous. I used the fog lamp switch for on off".

On 27 June 2012, Graham M V inMiddlesex, UK wrote:
"Mine iis the same as C Vassallo's except I used some left over vent tube, cut it down the length and wrapped around the exposed middle part of the pump, to disguise it completely. I use the F switch too".