Reply To: Vapour lock in a 49 BL.

[BernieParticipant]

In my experience, vapour lock in a 4-cyl tends to occur only if the rad and/or block are not in best condition, i.e. clean and deposit-free.

I have only experienced it myself on an engine which I later found to have about 25mm of solid deposits in the bottom of the block.  Quick roadside cure is to throw a wet towel or similar over the fuel pump and pipe to the carb.

The six is a different beast with a reputation for overheating.  My ’48 15/6 block and head were completely cleaned when I rebuilt the engine in 2017 but I found it still overheated in high temperatures and heavy, slow traffic.  I therefore fitted a newly recored rad. which, until last week,  solved the problem.  However, on the trip to the Polish ICCCR, we were stuck in a traffic jam for well over half-an-hour with an ambient temperature around 30°C.  When we finally moved off it suffered vaporisation but was almost immediately sorted by switching on the auxiliary electric fuel pump which I normally only use for priming a cold engine after standing.

B…..