Vacuum Tank problems

Joe30Essex

Took the Essex to a local show today. About 8 miles into my trip, the car dies. Not a drop of gas in the vacuum tank. This is the second time in 8 months this has happened. Seems that when the engine gets hot-it won't pull anymore fuel. I can sit and idle for a long period and no problems ( I can lay under the car and watch the fuel being pulled through a filter I installed-so I know the vacuum works). When this happens, the vacuum tank is very warm to touch. Any suggestions? I think I know why my grandfather put an electric pump on it years ago!

hudsonsplasher1

Joe,

I've got vacuum tanks on both my 28 Essex, and my 17 Hudson. I've never had this problem. Only thing I can think of is the vacuum shut off valve is not opening up to suck more gas into the tank when it's empty. Do you have a lever acton froat, or a bell shaped float? I think I would start by checking the vacuum open and close operation.

The problem I had with my 17 is, the shut off valve seat came lose and wouldn't allow the gas to shut off. The vacuum kept sucking gas directly into the engine bypassing the carb. A real mess. I'm suprised the engine didn't catch on fire.

I would try to avoid the electric pump if possible. These carbs are not designed to handle much pressure. Maybe try another vacuum tank and see what happens. Let us know what happens.

Gene.

Joe30Essex

hudsonsplasher1 wrote:

Joe,

I've got vacuum tanks on both my 28 Essex, and my 17 Hudson. I've never had this problem. Only thing I can think of is the vacuum shut off valve is not opening up to suck more gas into the tank when it's empty. Do you have a lever acton froat, or a bell shaped float? I think I would start by checking the vacuum open and close operation.

The problem I had with my 17 is, the shut off valve seat came lose and wouldn't allow the gas to shut off. The vacuum kept sucking gas directly into the engine bypassing the carb. A real mess. I'm suprised the engine didn't catch on fire.

I would try to avoid the electric pump if possible. These carbs are not designed to handle much pressure. Maybe try another vacuum tank and see what happens. Let us know what happens.

Gene.

Gene,

That is what's strange- I know the Vacuum is working. I can see the gas move when it activates, even the wiper works. It just happens once in a while, when I get going 40-45 mph for a distance. The only thing I was thinking about with an electric, is somehow using it as a back-up, maybe putting a switch under my dash and feeding the Vacuum Tank somehow.

ESSX28-1

Several times I've managed to empty the vac tank on my 28 Essex when climbing a long (2 - 3 miles) climb under full throttle & relatively low engine revs. I do this climb regularly & find if I pull over at the first sign (hiccup) & lift my foot for 10 - 15 seconds that the vac tank fill up & I can continue onwards & upwards. I put this down to not enough available manifold vacuum due to the long period at full throttle.

If you fill your carb (by popping the top) & then start the engine, will your vac tank fill before you use up the gas in the carb? If so, then your problem is unlikely to be in the vac tank mechanism & I'd look at the venturi on top of the vac tank (presuming you have a '30 vac tank & not an earlier one)

Joe30Essex

ESSX28-1 wrote:

Several times I've managed to empty the vac tank on my 28 Essex when climbing a long (2 - 3 miles) climb under full throttle & relatively low engine revs. I do this climb regularly & find if I pull over at the first sign (hiccup) & lift my foot for 10 - 15 seconds that the vac tank fill up & I can continue onwards & upwards. I put this down to not enough available manifold vacuum due to the long period at full throttle.

If you fill your carb (by popping the top) & then start the engine, will your vac tank fill before you use up the gas in the carb? If so, then your problem is unlikely to be in the vac tank mechanism & I'd look at the venturi on top of the vac tank (presuming you have a '30 vac tank & not an earlier one)

I haven't tried pulling over to see if the vacuum tank fills. I can tell when it is happening, as it starts to lose power. I do have an older version of the tank, much wider in diameter than the '30 tank. When I took possession of the car, it had an electric pump installed where the vac tank was supposed to be.

ESSX28-1

The '30 vac tank has some type of venturi gadgetry to stop the vac tank running out of vacuum. Perhaps your lack of gas is because you are using an earlier vac tank. Under what sort of driving conditions did your problem show up? Geoff Clark is "the man" where these vac tanks are concerned & also the source of my info on 1930 vac tanks.

Good luck

Joe30Essex

So, at the show today, a couple of guys come by to see if I made it. We start discussing the problems I've had, they look at the Vacuum Tank and tell me I should switch out the copper tubing I have. They were telling me it can get too hot, and that may be the source of my problem. Any truth to this? Could the copper tubing be causing problems when the car gets hot?

hudsonsplasher1

Joe30Essex wrote:

So, at the show today, a couple of guys come by to see if I made it. We start discussing the problems I've had, they look at the Vacuum Tank and tell me I should switch out the copper tubing I have. They were telling me it can get too hot, and that may be the source of my problem. Any truth to this? Could the copper tubing be causing problems when the car gets hot?

Joe, I know steel tubing is suggested for fuel lines, but, I've used copper tubing on my Essex for the last 20 years with no problem.

I think an earlier post from ESSX28-1 may be on to something. If your tank is to small, it won't keep up with the supply needed for your engine. Are you climbing any longs hills when this happens?

Gene.

oldhudsons

On my '29 Hudsons I'd put in a pressure regulator so can't get too much pressure + an elec. pump with switch so would only use it when necessary.

Joe30Essex

oldhudsons wrote:

On my '29 Hudsons I'd put in a pressure regulator so can't get too much pressure + an elec. pump with switch so would only use it when necessary.

How did you tie that into the Vacuum Tank or Carb.?

Joe30Essex

Gene and Dave Y..

Was just in communication with Geoff Clark about an hour ago. He suggested a few things. I took off the connections at the top of the tank. Noticed on the vacuum connection at the engine there was a black soot type of layer around the top of the connection and the pipe-possible leak there. Geoff also suggested checking all the fittings, which I am now doing. He was in agreement with you, Gene, that the copper tubing should not be a problem. One other thing-I'm not so sure the pin at the bottom of the float was seating correctly. I am also going to cut a new gasket for the top. Hope something works! Thanks for all the suggestions.

Joe

oldhudsons

Joe - you may want to use that thin white tape plumbers use to stop leaks on the threads when you re-attach the line to the tank.

Joe30Essex

oldhudsons wrote:

Joe - you may want to use that thin white tape plumbers use to stop leaks on the threads when you re-attach the line to the tank.

Will do- Thanks!!

Geoff

NO,. NO , NO!!!!! TEFLON TAPE MUST NOT BE USED ANYWHERE ON GASOLINE LINES. IT WILL SOFTEN AND LOOSEN UP, AND STRANDS OF TAPE ARE LIKELY TO GET INTO THE INTERIOR WORKINGS. Pardon me for shouting, but this is important. With copper lines all you need is a good swaging surface, and tighten up metal to metal.

Geoff.

Joe30Essex

Geoff C., N.Z. wrote:

NO,. NO , NO!!!!! TEFLON TAPE MUST NOT BE USED ANYWHERE ON GASOLINE LINES. IT WILL SOFTEN AND LOOSEN UP, AND STRANDS OF TAPE ARE LIKELY TO GET INTO THE INTERIOR WORKINGS. Pardon me for shouting, but this is important. With copper lines all you need is a good swaging surface, and tighten up metal to metal.

Geoff.

Good thing I haven't gotten to that point, yet. Thanks, Geoff

hudsonsplasher1

Joe, another thought, I would check for any restriction in the gas line. Maybe something is slowing the flow of gas enough to starve the tank at some point.

Joe30Essex

hudsonsplasher1 wrote:

Joe, another thought, I would check for any restriction in the gas line. Maybe something is slowing the flow of gas enough to starve the tank at some point.

Gene,

I'm in the process of putting in a new line from the engine to the tank. When I had my car painted last year, the shop pulled the Vacuum Tank away from the firewall, and left it with the tubing bent to the engine. I think I may have had a small leak there (at the engine). Also, the tank was a little cockeyed, so I'm not sure the float was seating properly-leveled that last night. Once I get all this hooked-up, I'll get underneath the car and check to make sure the gas line isn't kinked anywhere. This Vacuum Tank worked great before I had the car painted, so I'm checking things (per Geoff's suggestion) as they were before I started having trouble.



Joe

Joe30Essex

hudsonsplasher1 wrote:

Joe, another thought, I would check for any restriction in the gas line. Maybe something is slowing the flow of gas enough to starve the tank at some point.

Gene -

This was the culprit of the whole problem. Last night I hooked-up an electric pump which I knew worked to see if it could pull gas to the engine. (Yes, it's an old 6 volt Stewart my grandfather put on the car when he got tired of vacuum tank problems. I had it rebuilt and tested a few years ago just in case...) Well, it pumped and pump and just a small stream came out-probably just enough to keep the engine idling. Today, I dropped the gas tank- took out the pick-up tube and there was the problem(s)---not only was the copper twisted, but there was a long glob of old silicone gasket material at least 3 inches up the tube. Made new pick-up and breather tubes, this time used a CORK GASKET, cleaned-out the gas tank, and put a whole new fuel line in...just in case it was full of crap.

Ran the car for 1/2 an hour, got it good and hot-no problems. I will street test it in the next few days. The Vacuum Tank, which had been getting pretty hot to the touch, was cool and seemed to be full of fuel. I hope this takes care of my problems.

Thanks to all who responded-you kept me thinking!

hudsonsplasher1

That's good news Joe!! Looking forward to seeing you and your car at the national.

Gene.