Re: Posible vapor lock solution?

Posted by Craig Hendrickson On 2012/6/29 11:52:06

To add one more recent anecdote about vapor lock:

Last month I had occasion to drive my 55 Pat from Pahrump to Las Vegas, NV in 100F+ ambient heat. I went in the morning and returned in the late afternoon and drove around Las Vegas traffic off/on during the day on a series of errands.

My 55 Pat has stock fuel system except for the addition of an inexpensive NAPA pulse-type fuel pump mounted in the inlet line below the driver door.

100F+ ambient in Las Vegas stop/go traffic means 120F+ air temp at grille inlet. When caught in this type traffic, my Pat was right on the verge of vapor lock as evidenced by stumble and minor/quick cutout of power. Once moving, even in this traffic, the vapor lock did not manifest itself.

On the way back to Pahrump in the late afternoon with ambient temp still over 100F, my Pat was able to pull the long grade from I-15 (2200ft elevation) to Spring Mountain pass (5400ft) without a whimper. Of course this was at 55-65mph with attendant airflow.

I knew from previous experience that without the electric pusher pump (~3-4psi) my Pat would have vapor locked.

Craig