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Greetings All,

Has anyone had any experience with adding a low pressure fuel pump to assist or replace the vacuum tank? I think my vacuum may be starting to fail.

Thanks
Gene

The collective experience of folks with vacuum tank cars is that booster pumps feeding a vacuum tank can be problematic, and also pose a fire risk. IMO your best bet is to have the vacuum tank repaired.

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The usual method is to bypass the vacuum tank completely and go directly to the carburetor. However, this also requires a new needle and seat to work properly because the vacuum tank is gravity feed.

The vacuum tank can be repaired as noted and will work without the need for cheesy pumps. I personally like the vacuum tank because those cars can sit for years and years and years and still run whereas fuel pumps break.


It does, however, require a good clean tank and the pickups in those cars develop pin holes that suck air, so your problem may not be the vacuum tank at all. As well the fuel lines need to be air tight. I always used Permatex #1 hard setting sealer on the fittings so the they would seal without excessive force although Permatex #2 will work as well.

Thanks for the info, I'll take the tank apart to see what's happening as I had replaced the float springs some years back.

Gene

Thanks,

I'll reach out to him to get some information on a restoration.

Gene

I have a 1930 733 2/4 Rumble Seat Coupe. I could never get the vacuum tank on mine to work right even after rebuild. I by-passed the vacuum tank and installed a low pressure fuel pump (4 lbs.) and installed an in-line Moroso regulator that I set at 1 1/2 lbs. pressure to a David Frear Detroit Lubricator Carburetor. I did that 3 years ago and it has ran sweet ever since.

Hi Mike: I sorry you couldn't get the SW vacuum tank to work, they normally are utterly reliable, more so than mechanical or electric pumps. But what I found particularly interesting and glad to hear is your satisfaction with the Dave Freer DL. That project certainly got off to a tumultuous start but those who followed it were hoping it would succeed, and we all waited for the 1st report of a completed unit giving good performance - and yours is the first such report I've heard.

Well, on the vacuum tank, I spent $150.00 getting it rebuilt and I messed with it for months and gave up. I have 4 Packards, 1930, 2 '41's, and a '50. I try to keep them factory original, as They worked fine like that when new. This is the only un-original thing on all my Packards. If I get the patience sometime, I will try the tank again. My set-up is working.

I have had good luck with David Frear. He has worked with me on issues, but none were ever major. That carburetor is like a piece of fine jewelry. It works very well. When undertaking a project of that scale there are bound to be difficulties and trial and error. As I said, this carb has been on my car for 3 years now, and it runs nice as can be. I recommend that carburetor to anyone for the proper application.

I have a good, longstanding reputation, and I intend to keep it that way.
Thanks,
Mike

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 fromvintageandclassicreproductions.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.

Mike,

Who did you get the fuel pump and regulator from? I've also been working with Dave on a carb for mine. It has been through the R&D process and am awaiting a new float.

Does your carb have the different needle valves to accomodate the fuel pump?

Thanks
Gene