Re: vacume tank or vapor lock 1929 626

Posted by DavidM On 2012/9/2 17:49:39

In addition to Tim's good advice there is a lot of information on line on how the vacuum tank works. Its a simple and usually trouble free device and its worth spending a little time understanding how it works.
Vapor lock is not so easy, one of the problems in diagnosing it is that it does not occur all the time. You can drive the car in hot weather and convince yourself you have fixed it only to find that it comes back when the conditions are "right". I have restored 2 633's and the second one incorporated all that I had learnt from the first. On its maiden run of about 2,000 miles it performed flawlessly only to vapor lock on a long steep climb on the last day. A wet rag on the carburettor and vacuum tank had it going quickly but up to then I thought I had the dreaded vapor lock issue beaten. I have since fitted the standby electric pump and it could be a while before I get to test it under actual vapor lock conditions.
29tons,I hope you update the forum with progress on you 626.