jagnweiner

That's great! My brother has a '23 touring that looks a lot like yours. Maybe I'll follow your lead and take a few pics of my '25.

You can just call me Scott. That is where the filter was; it is no longer there as I have replaced it with a short piece of copper. If you happen to have access to a fax machine, I would greatly appreciate a copy of that printout. I can send you a PM with the number. Otherwise, maybe someone else has the material you're referring to. I'm going to get the tank cleaned out anyway, because it needs to be done. Thanks, Scott

Richard- Glad to hear you're getting closer too. Having had my vac tank apart, I know the new float has no cracks. You probably already know this, but once you take it apart, you can find the cracks in the float by heating a pan of water to just shy of boiling and immersing the float. Air bubbles and gas will come out of the float at the various cracks. Use the same test after soldering to confirm that you fixed it. Others with more knowledge may elaborate on that process a little.

This morning's update and responses to questions: -I have not taken the carb apart or done any adjusting of it. -I recant my previous statement that plugging the line off the manifold would cause it to die; slight change in rpm but still runs fine. -I hooked up copper tube where the fuel filter used to be and ran it to a can of gas sitting on the floor. It ran pretty well and was drawing fuel from the can to the vac tank. Ran the engine for about 15 minutes that way. -I drained the remaining bad gas from the gas tank (about 4 gal) and took a flashlight for a closer look to the inside of the gas tank. Things don't look great in there. It looks like someone applied some sort of sealer coating that is now starting to peal away. I suspect there is a fair amount of junk at the bottom of the tank and the pick up tube may be sitting in this junk. The drain plug is in a small indentation in the bottom of the tank. Is the pickup tube supposed to sit down in this indentation? Ultimately, I think I need to get this tank cleaned out. -Scott

Jim- I see your point. I'll have to re-check my observation on what happens when vac line to the manifold is disconnected from vac tank and then plugged by finger. Yes, the engine runs fine when the the gas line is disconnected and there is fuel in the vac tank being gravity fed to the carb. -Scott

Billy- Float is definitely fine. It is completely different from the one I got back "rebuilt." (I suspect your "major DB parts supplier" may be the same person that rebuilt mine, but he shall remain nameless) It has two springs and is working fine. I see your point about black smoke indicating flooding, but it happens so quickly after hooking everything back together, that I don't think fuel is being drawn from the gas tank. The vac tank is not overfilling or overflowing (the vent tube works fine also). 72caddy, I cleaned all the scale off and the gas tank pickup tube is clear when I reinstall it, but it is possible it is picking up a bunch of crud as soon as I put it back in. Bottom line, I think the experiment of trying to draw fuel from a separate container will give me more answers. I hope to try it tonight and will let you know what happens. Thanks again, Scott

Apologize in advance for the length of this post. I'll give a very condensed version of my saga and then get on with the questions. I have a '25 DB Touring that for several years was a very reliable driver. About 8 years ago, I began having fuel problems which I attributed to vacuum tank problems. Car runs great for 5 minutes after manually filling the vac tank, but dies as soon as vac tank is empty. I sent the vac tank off for a rebuild, but wnen it came back, it had cracks in the float. I eventually got an entire replacement top and mechanics (everything but the inner and outer tank). Never quite got around to chasing down the problem over the last several years. I bought an electric fuel pump and pressure regulator a year ago to bypass the vac tank, but didn't get around to installing it either. This week, I finally got motivated to troubleshoot this problem. I first disconnected the vac line running from the manifold and checked for vacuum. I don't have a guage, but it had enough suction to suck on my finger pretty well. Plugging that line also causes the engine to stumble and start to run rough. (Not sure if that is a clue) I then disassembled the vac tank and checked the two valves on top. Both seem to seal fine. I put everything back together and tested it. With the engine running, but the fuel line from the fuel tank disconnected, I now have vacuum at the fuel inlet. Again, when I plug the inlet with my finger, engine stumbles and dies. I next started working my way back to the fuel tank. I took off the aftermarket inline fuel filter halfway back to the tank. I ran it with the line open where the fuel filter was. Again, runs fine open and runs rough and dies when line is plugged. I then bypassed the filter by installing a piece of copper tube and it wouldn't run. Went all the way back to the fuel tank and disconnected the fuel line where it exits the top of the tank. Ran fine while disconnected, ran rough and died when hooked up. I then took out the fitting and tube that go down into the tank. It was in kind of tough shape, with what I would describe as "plaque" on it. It also appeared to have some kind of attachment at the bottom (a screen?) that was corroded away. I cleaned it up and re-installed. I started it back up and running was pretty much the same. Ran very rough, firing puffs of black smoke out the exhaust. It seemed like it might have been a little better than before, but I think that could have been because I was a little more persistent in keeping it running. I ran it with the filler cap on the tank both on and off. When I put my hand on the filler hole, there seemed to be some suction there. At that point, I was ready for bed. Any thoughts, wise ones? FYI, there is about 1/4 tank of fuel in it. I have drained the tank and added new fuel, but it has been a while, so the fuel could be stale. I also plan to try connecting tubing at the fuel filter bypass to draw fuel directly out of a gas can. Thanks, Scott

Any thoughts on this last question? I'm hoping to install the pump this weekend. I'm starting to lean toward just using it to fill the vac tank. Thanks, Scott

OK, tonight I went out and found a pump and a regulator and some copper tubing to create my bypass. Now my question/problem is this. The pump says it is for 12V negative ground systems only. Is there I way I can make the pump negative ground while the rest of the system is positive ground? There is a switch already wired from when it previously had an electric pump. It appears that it got its power from the ammeter. Would this have something to do with it? Thanks, Scott

Thanks, Dave. How low is low? I can get a pump that is 1.5 PSI. Do you think that is low enough or will I need a regulator? -Scott

What kind of PSI should I be looking for at the carb?

OK, here's the deal. I have a 1925 DB touring that has been a great driver for several years. I have, however, had problems with the last few years with the vacuum tank. After it quit working, I had it rebuilt once by Romar. When I got it back, it still didn't work and I discovered that the float had cracks. I got some parts from another tank to repair and still cannot get it to work. I am not giving up on the vac tank for good, but I want to get this thing running again in the meantime. I would like to install a temporary electric fuel pump that bypasses the vac tank. I'm not concerned about stock appearance and I eventually want to get the vac tank working again, so I don't want to try to conceal it inside the shell of the vac tank. Can someone walk me through how I can do this? Thanks, Scott

An interesting example of differing terminology. What we Yanks would call the top, the Aussies call the hood. What we call the hood, they call the bonnet. Our trunk, their boot. Etc.

My '25 Deluxe Touring could be for sale for the right price. Older restoration that is a nice driver. Contact me @ sjohnson@larkinhoffman.com

Thanks for the advice, but I need the whole rotor. I had borrowed this one from my brother and had to give it back. Lost my spare. It's a long story. So I still need to purchase one somewhere. -Scott