Packard Forum Index » Pre-War (1899-1942)

Hi All,
1927 Packard 6 is leaking gas from the overflow line on the vacuum tank. I have included two pictures. The middle thin line runs out of the top rear of the vacuum tank, attaches to the back of the firewall, and empties right above the rear of the head. Does anyone know why this is leaking gas when the car is running?

Thank you much,
Rich

Attach file:

---

  (40.79 KB)


  (46.22 KB)

I haven't played with a vacuum tank so hopefully one of the guys that have a similar car will have a definitive answer. Looking at the cutaway drawing and reading how the valves and float operate I wonder if it could be due to a faulty float or valve letting the tank get too full. The positioning of the leaking vent tube and it's inside port looks slightly lower than the other tubing so possibly if the tank is getting too full a bit of siphoning thru the vent tube might be happening.

Here is a Stewart operation manual published in 1927 for a tank which looks similar. NO idea if it is the proper writeup for your unit but it looks like it may be. I have a later manual which looks to be for a unit with a slightly different appearance.

Attach file:

---

Size: 510.83 KB; Hits: 86

Defective float and/or float valve.

It just so happens that last week we had a similar problem with out '27 Six Convertible Coupe.
In our case, the gas was being sucked into the carb and flooding the engine.
We discovered that the float was good,but that the needle valves had some buildup and were sticking. A good dose of carb cleaner and the needle valves are working flawlessly and we are cruising up and down the street.

Hope this solution works for you.

Bob

Good info Bob, thanks. Did you open the vacuum pump and clean it out? Is that where the needle valve is located, or is the needle valve in the carburetor you are speaking of? Any pics would be great.
Thanks, Rich

I opened the vacuum tank...the 8 screws and the mechanism lifts out. Tomorrow I will get a couple pics.
There is a lever, two springs, and two needle valves.

Here's a pic of our '27. It was restored '63-65 and pretty much in hibernation since '71.

Attach file:

---

  (82.57 KB)

Ooops...I had earlier mis-stated my problem...

Because the valves were not working properly, the vacuum was sucking the gas directly into the manifold...NOT into the carb....thereby bypassing the carb and flooding the engine.

Thanks Bob! Awaiting your pics, then going to disassemble the tanks, conduct a nice cleaning, and should be good to go!!

Here's the bottom of one of my spare units. Yours probably looks very similar.
The two needles have to move freely.
Be careful with the springs, they are fragile.

There is a Packard owner in Texas who restores these Stewart Vacuum units if you need a professional restoration.

Bob

Attach file:

---

  (192.61 KB)