WPVT

If you Google search "rear seal / stovebolt", you'll find a lot of information on replacing the rope seal in old Chevy 6 cylinder engines. I used to have one years ago, and replaced the seal with the crankshaft in place several times, never successfully. Eventually, I tore down the engine and did a nice tight job of it. So tight, in fact, that the engine wouldn't turn over, even when towed. I am sure others have done better and learned more. Finding the seal material itself should be relatively easy. It used to be supplied in two halves, oversize length, for trimming to fit. The Chevy seals were called rope seals, but in fact, they were rectangular in cross-section, not round like a rope. Installing the seal successfully can be a challenge, though. Good luck to you.

I just replaced some fuel line and so I had to brush up on my copper tube flaring techniques. Everything I read said that compression fittings were for water or air only. Any liquid or gas considered dangerous should be done with a flared fitting. The consensus was that compression fittings will loosen with vibration whereas flared fittings will not. All natural gas or propane lines are flared, as are any older copper gasoline automotive fuel lines I've seen. The copper flare used is a 45 degree, also called SAE type. Maybe this is outdated information, but it was certainly true in 1954. A one piece line certainly has an advantage. Whatever fittings you use will likely be accessible.

Yes. The updraft Zenith is opposite.

I have the vacuum fuel tank operating well on my 1929 White truck. While tinkering with the windshield wipers, I tested the vacuum at the manifold. A nice, steady, 16Hg, which seems reasonable. It's a 260 cubic inch 6 cylinder. Here's my question; When I disconnect the vacuum gauge and leave the vacuum line open, the engine idle speed increases, and it actually seems to be smoother. It seems to me that doing this would make the mixture leaner, since I'm adding air to the mixture. Yet with everything reconnected, I can't adjust the idle mixture screw to get that same result. It's an old Zenith updraft, and backing the mixture needle out will only make it so lean and that's it. Could it be that a carburetor jet needs to be modified? Or is what I am seeing normal. In short, I wish I could get it to idle as nice with the vacuum line closed as when it is open and disconnected.

I did some testing and found that cranking the engine with the starter produced very little vacuum at the tank. Certainly not enough to draw gas. So I checked vacuum at the intake manifold and found the same. Conclusion...starter cranking cannot generate enough vacuum to draw gas, even with everything working as it should. So...I primed the vacuum tank, and started the engine. Everything is working fine. Idle isn't quite as smooth as before, but maybe there's a tiny vacuum leak somewhere. I'm off the electric fuel pump and running on the vacuum tank. First time in many years. Thanks for all of the helpful hints.

Thanks. It was my understanding that the vacuum generated by cranking was sufficient to draw gas into the tank. But maybe I am wrong. Certainly a running engine would do a better job of creating vacuum.

Thanks. I didn't notice the earlier post since it referred to a Stewart fuel "pump". In reading the PDF (very helpful) I found reference to the valves possibly not working if the tank was dry. I'll add a little gas and see if that seals things up.

I rebuilt and reinstalled the Stewart Warner vacuum tank in a 1929 White truck. I turned over the engine for 20 seconds or so several times, but no fuel has reached the tank. The line between the vacuum tank and the fuel tank is clear of obstructions and leaks. The vacuum line to the manifold is only about 20" long and it is also sound and free of leaks. Can anyone suggest a troubleshooting test while the tank is still installed on the truck? The tank and internal mechanisms were in very good shape when I disassembled it, and I was pretty careful during reassembly. The float looked perfect as did the brass parts. Is it reasonable to expect the engine vacuum while cranking to be sufficient to draw gas up into a dry vacuum tank, or do things need to be wet to function? I didn't want to put gas in the vacuum tank first; That way if I saw gas in the sediment bowl I would know it was working. I suppose I could put a vacuum gauge at the fuel inlet, and that might narrow things down. How much vacuum should I have at the fuel line? Thanks.

Thanks. That's what I thought. Somebody just saw the air tube and the dangling wiper hose and decided to put them together. Somebody else probably plugged the correct tee years ago because the wipers were leaking vacuum.

My 1929 White has a Stewart Warner vacuum tank to provide fuel to the carburetor. I'm putting it back into operation. The vacuum inlet fitting on the tank has an old (and maybe original) tee branching off that was intentionally plugged at some point. I assume this was for the Trico vacuum wiper motor. At some later time, someone ran the wiper vacuum line to the air vent tube on the vacuum tank. They may have just seen the bare vent tube and the wiper hose hanging nearby, and thought they were reconnecting it. Is my intuition correct? Running the wiper from the air vent tube seems like a questionable idea. It's difficult to determine what was original, since the cab (and wipers) were manufactured by a different company than the chassis. For this reason, parts such as wipers are not covered in the White parts or maintenance book. Thanks.

Thanks for all the advice. I'm fortunate in that the tank and mechanism appear to be in very good condition overall, so nothing very drastic will be necessary. I'll clean and reassemble and see if there are any problems. Thanks again for all the helpful replies.

I intend to use the fuel vacuum tank on a 1929 White truck, and to that end, I purchased what I felt would be the necessary replacement parts. As it turns out, the tank is very good on the inside. Some light surface rust on the tank shells, and some typical white corrosion on the pot metal top. Everything else is pretty pristine, including the phenolic flap valve, brass parts springs, etc. I think I'll keep the old valve rather than use the replacement I bought...it looks that good. My plan is to shake some shot or something similar inside the tanks to clean up the light rust. I am wondering whether I should try to coat or paint anything interior or just let the fuel keep the rust away. I'm sure there are members with lots of experience doing this work and I thought I'd ask for advice before I move forward. Thanks.

Thanks. Since posting I have learned that this updraft Zenith mixture needle threads in (clockwise) to enrich the mixture, and out (counter-clockwise) to make the mixture more lean. One and a half turns out is still the best place to start.

Here is a list of serial numbers by year...

It might make a difference if and when the coil leaks. The rubber boot on my inverted 40 year old coil was holding back about a tablespoon of oil. It still seems to work OK, though. An upright position might help keep the oil where it belongs.

Jon, That's a good tip to keep in mind. It's amazing that a few inches of head could make that much difference. As you may recall, I was having trouble with a 1941 surplus Type 63 Zenith updraft being used on a 1929 White 260 cu in 6 cylinder. The carburetor was running dry after a few minutes at high idle. The truck originally had a vacuum system but is currently using a 3-4 psi electric fuel pump. So I took the carb apart and recorded all the jet sizes, etc. Here's what I found: Venturi size: #28Inlet valve: #40Main jet: #25Discharge jet : #25 That seemed like a small inlet valve orifice, even for an electric pump, so I drilled it out with a #36 drill (.1065"). Now it runs fine. I intend to rebuild the vacuum tank, so we'll see how it does when it runs on gravity. Trial and error worked for me, but I'm wondering if there is a more scientific way to size the jet when a carb is being used in a different vehicle than it was intended for? Walter

Try Bon-Ami. I find it very effective and not at all harsh. It contains ground feldspar and a coconut derivative.

Would anyone know how the idle mixture needle screw works on a Zenith 2136016 (9786) carburetor? I am used to in/lean, out/rich, but I know that some older carburetors operate the reverse of this. Thank you.