On 6/23/2010 12:21 PM, Pete C. wrote:

Don Foreman wrote:

(...)

What happens with a 5 gallon jerrycan with 1.5 PSIG inside? Well, the
vapor pressure of "summer" gasoline varies about 3.5 PSI from 50F to
90F, so a jerrycan certainly can handle 3.5 PSIG without problem.

A 20 l jerrycan has about 10% the internal surface area of a 55 ggl drum.

http://www.harborfreight.com/12-gpm-...ump-93755.html

Has 10psi relief valve, so presumably a standard 55 gal drum can handle
10psi.

In cursory Googling, I've seen specifications from 5 PSIG to 43.5 PSIG.

As someone mentioned, there are economical pumps available that would
place insignificant pressure on the contents, though.
I would choose that safer alternative.

--Winston -- Needs to buy a new compressor to dispense coolant to
machine a part to repair the old compressor.
No. Wait....