Re: Fuel Pump conversion for 1930 733

Posted by DavidM On 2015/5/9 19:22:05

I agree with Dave's comments about the reliability of vacuum tanks, I have them in 3 cars running perfectly over many years.

There is ample information on the net about how they work but I am sure you have all that figured out.

One thing you might check is the top. I have replaced the original pot metal tops in all of mine because many years ago I had a vacuum tank that refused to work despite everything looking OK.

The seats in the tops are small brass inserts cast in place when the tops were made and in my case although the top looked good it had swollen around one of the seats and it was loose. It took a while to realize what had happened. After fitting a repro top it has worked fine for 20 years. I know of others who have had the same problem, some people Loctite the seats back in but I prefer a new top because they are prone to cracking around the threads etc.

New aluminum tops are available on line fromhttp://www.vintageandclassicreproductions.com/.
Not cheap but fully machined and superbly made.

Finally I have fitted a fuel pump bypassing the vac tank on one car as a trial to overcome vapor lock. It works well but is only used when absolutely neccesary. The pump is the low pressure one and the original carburetor needle and seat does not flood with the pump operating.

I hope you stick with it and let us all know what the problem was.