PFitz

Be advised, the 6 volt come in two different pressure outputs. The Airtex E8011 is rated 5-8 psi. The E8902 is rated 2.5 to 4.5, which is a closer match to the output of many early mechanical fuel pumps. I have a customer who someone put a higher pressure pump in the car and it once jammed the float needle. He doesn't dare use it full time, only for priming. Whereas the original mechanical AC pump on his car is rated at 2-4 psi output, with the E8902 he could run it full time and not have to worry about over-stressing the float & needle. Plus, anytime you change the fuel pressure, you also change the float level in the carburetor. For a backup pump, you want the electric pump's pressure to be close to that of the mechanical pump's pressure so that it doesn't change the float level a lot when you have to switch on the electric pump. Paul

"Tension" is an old term for "voltage". The "Low tension" system is the 6 volt wires to the ignition switch, the coil, and to the side terminal of the distributor head for the points and condenser. The "High tension" system is the high voltage wires from the coil to the middle of the distributor cap, and from the cap to the spark plugs. Don't use modern spark suppressive wires with a 6 volt system. In a short time the carbon impregnated fiberglass core gets burned out causing even higher resistance until no spark voltage gets through. Use "solid core" spark plug wire like Rhode Island supplies. It's made with modern insulation over stranded copper wire, then cloth braided and clear lacquered to look just like what would have been on your car originally. And RI Wire has the correct type terminal ends. Solder them onto the spark wire if possible. One other thing many misunderstand is that for a 6 volt system you should use size "0" battery cables, because 6 volt starters need more amperage to do the same work (watts) as a 12 volt system with it higher voltage - lower amperage equaling the same wattage. Paul

For all my 20's and early 30's restoration's wiring needs, Rhode Island Wiring Service. http://www.riwire.com/ They carry the braided, lacquered spark plug wire in black and various color codes depending on what the original was. They even have new wiring harnesses for the 29, GP model 612 and 621. Paul

You'd be amazed at how fast (and how little "elbow grease" is needed) using a roll of paper towels and a can of fast lacquer thinner can quickly turn "brown walls" into white walls. Good idea to wear Nitrile gloves to protect your hands. Paul

There's a quote supposedly attributed to custom coach designer Ray Dietrich, " It's called a coupé,..... coops are for chickens". https://en.wikipedia.org/wiki/Coupé Paul

I would doubt it too, since that was on a 30 engine that was originally 5.1:1 compression and then highly modified during a rebuild less than ten years ago to make better use of todays higher octane gasoline to increase engine efficiency. I only posted the numbers to show that you can get a "rough idea" of compression ratio based on what the compression readings are. Other engines of that same era will likely vary based on the cam design. And with Scott's motor, It's not unusual that a newly rebuilt engine will give lower readings which should come up as the rings wear in. Plus, after enough miles to break in, the lower compression older engines, being less efficient, can build up carbon layers in the combustion chamber and the piston top, that then not only helps seal the rings better, it takes up volume in the combustion chamber thus raising the compression ratio above the original measured ratio. Plus, if the cylinders were bored out, and or, new taller pistons installed, and the block and head were milled, those will raise the compression based on how much those changed. Paul

That 7:1 is measured compression on an engine that I also measured the actual combustion chamber and swept volumes with a graduated cylinder after raising the compression ratio. Compression ratios are just that. However, engine compression readings can vary for the same ratios depending alot on camshaft design and secondly, a few other factors such as the starter motor speed being strong or weak when doing the compression test. Plus, that 7:1 engine is using Total Seal's "gapless" ring set, which gives slightly higher compression and vacuum readings once the motor is properly broken-in. Paul

If it is octane related pre-ignition, running on high test should make it go away. Any hot spots in the combustion chamber can cause it too. As far as how high your compression is now, you can get a rough idea by what the compression readings are when the motor is more broken-in. 5:1 gives about 75 pounds. 7:1 about 115 to 120.....etc. There are charts to get an idea. Otherwise to know more accurately, you need to measure the cylinder volumes with a graduated cylinder and oil. Paul

As soon as your picture loaded, that chrome band had me wondering too . So, I just did a Yahoo search of, "1937 Nash Lafayette 400". There's lots of pictures come up showing them with running boards - all the Victorias, coupes, and the four doors. Plus pix of many that were rodded and still have the running boards. Paul

What you describe is exactly what happens with vapor lock. But it can also be a coil going bad from heat. Usually when it's a bad condenser it quits after a few times of running bad and it won't start even when it cools down. With vapor lock, it starts out turning the carb lean and starving for gas, which gets worse because a lean engine runs hotter, dumping more heat into the engine bay and under the car around the fuel system. With the coil, the higher cylinder pressures of an engine under load make it tougher for the coil to jump the spark gap. To quickly cross vapor lock off the list of possibilities, try wetting down the fuel pump, fuel lines, and carb, with wet towels and see if you can get that twenty minute wait to restart reduced to just a few minutes without doing anything else. Then, if that made no noticeable difference, get it hot enough again to stall out and if it's the coil, or condenser cutting out, there will be no, or barely any spark at the plugs. Once you determine the cause, if it's a bad coil then changing it should eliminate the problem. If it's vapor lock, there are a number of things you can do to deal with that. Paul

Good point about pullers under great tension springing off - especially with the additional flexing of those three right-angle brackets bolted to the drum. There is room enough that the axle shaft nut can be left on loosly and not interfere with the puller. Then the drum and puller can't fly off when the drum finally loosens. Paul

A heat gun can't put out enough BTU's to get that much hub metal hot enough to expand it to the point to help break the taper's hold. MAP gas torch is a minimum - oxy torch is better A trick I learned way back when I worked in a couple of boatyards. We'd get stuck propellers off power boat inboard engine shafts by first hammering the propeller hub right above the keyway. Use several strong blows along the length of the keyway. Then put the puller on, tighten it, and go at the hub with the torch. Paul

The spring acts like a rotating shock absorber, tightening the coils when the spinning Bendix gear first meshes with the non-moving ring gear, thus reducing the chances of shock damage to the teeth. Paul

Going by the number I've had to replace over the years, the recoil spring is the Bendix's most common weak link. The springs work harden over the years and then snap near one of the ends. Followed by the spring bolts shearing off. I keep spares of both on hand. I see that you have a left-hand Bendix spring. That means you can get replacements springs, bolts, and lock washers at Snyder's, or Mac's Auto. Check the bolt size because Snyder's has them in a couple of sizes for early, or later Fords. http://www.snydersantiqueauto.com/search?q=Bendix http://www.macsautoparts.com/ford_model_a/engine-and-related/starters/starters-and-solenoids.html As for the gear teeth, often, just the ends of the teeth are chewed up. If you look you'll see by the wear marks that the Bendix gear teeth rarely seat full length into the ring gear. Often they can be cleaned up with a small stone bit in a Dremel tool. Then grind a bit of metal off the end of the gear to allow the cleaned up teeth to once again engage the ring gear teeth as much as the Bendix gear travel will allow. Paul

Usually, if any part of the fuel system is too hot to comfortably hold your hand on it, then vapor lock is a very good likelihood. If putting cool, wet paper towels on the fuel pump and carb, or spraying cool water from a plant sprayer on them (don't get a lot of water inside the carb) to quickly cool them down, lets the stalled engine restart sooner , that is another good indication that the problem is vapor lock. Paul

Your welcome. Glad to hear it's working ok. Actually, it's the ring gear that disengages the Bendix. A simple device that works because of the very large difference in gear sizes. Once the engine is running, the far larger diameter of the ring gear has a faster gear teeth speed than the little diameter of the Bendix gear. The ring gear then spins the Bendix gear back down that spiral shaft away from the ring gear. Paul

If you make the drums thicker that will increase the drum circumference. You might want to first check to make sure that the brake bands will still fit around the drums and work safely. Paul

The large bearing near the pinion gears is to take the radial load of the pinion gear shaft. The other set of caged ball bearings near the drive shaft end of the pinion shaft is to take the axial thrust load. You thread the pinion housing into the differential housing to adjust how deep and where along the teeth that the ring and pinion teeth mesh. Same with how the ring gear is centered - sometimes by threaded bearing holders, sometimes by shims. You don't want the tooth load at the ends, or near the edges of the teeth - where they are weakest. Using white grease as a paste to lightly coat the pinion's teeth, the grease will show where it gets wiped clean by the ring gear, thus showing the "contact patch" of the gear teeth. Ideally the load contact patch should be near to center on the teeth as possible. You also don't want the gears to mesh too tightly. Typically about .005 to .006 of "backlash" play - movement in the ring gear before the pinion moves. Paul

Looks like a good wire brush cleaning would help that spiral and gear. 6 volts isn't all the starter needs. Your bench setup may not be delivering enough amps to "snap start" the starter motor fast enough to spin that Bendix gear toward the flywheel ring gear end of that Bendix shaft spiral. Or, polarity may be wrong and the starter motor is spinning it the wrong way. All the Bendix drives I have here from that same era, that spring-loaded "pin" rides up top of the spiral thread. It's there to provide some drag to hold the Bendix gear disengaged once the engine fires and spins that gear away from the flywheel's ring gear. Otherwise engine vibration and road bumps may move the Bendix gear back into brushing up against the ring gear teeth and wearing the teeth prematurely. You should be able to smoothly move the gear along it's spiral by hand, but feel some drag so that the gear won't move very easily. Turn the shaft on end and see if the gear stays near the top of the shaft without it falling down the spiral shaft of it's own weight. Paul

Agreed 100% !!!!!! And a good sized 6 volt battery. I've seen some that were way too small to deliver enough amperage to fire the coil with the voltage drop of a starter motor always winning the "amperage tug-of-war". Plus, not having good, clean electrical connects and grounds, are the other main problem that 6 volt systems get a bad rap. Oil migrates into electrical connections and being that it is an insulator, it makes for poor connections with lots of resistance to current flow. Plus, paint is also an insulator. In a single wire system, often the wire connections are fine, but with a re-painted car, if whoever assembles it fails to establish good ground connection paths back to the battery through the body, fenders, and chassis, there's lots of resistance causing poor, or no grounding. Paul

Your welcome, Yup ! I love to hear a properly operating vacuum tank drop the engine rpms slightly as it cycles to pull fuel up from the tank. Paul

Many of the early mechanical fuel pumps of the late 20's early 30's were only rated to put out 2-4 psi. It's not fuel pump pressure so much as pump output volume that you need to be concerned about. If your vacuum tank is re-buildable, it will supply plenty of volume. If it's not re-buildable and you opt to use an electric pump, chose a low pressure one and check the running float level after it's installed. Any change in fuel pressure is a change in float level and many of the later updraft carburetors are VERY sensitive to changes in float level. Paul

One way to avoid alcohol related fuel problems is do a search for "e-free" gas. Many of the gas stations here in CNY have switched over to 91 octane that has no alcohol in it. About 50 cents more a gallon than regular, but no other expense from the alcohol, and the water it absorbs, affecting the steel and brass parts of fuel systems. Paul

Not just today - the changes came many years ago. Thanks to the internet, those in the "hobby" are just catching up to what those of us in the professional restoration business have been dealing with alcohol related fuel problems for about thirty years now. Back in the 80's many antique owners (myself included) were finding their carbs and fuel pumps filled with a sticky, yellow mess that used to be the gas tank sealer. Alcohol in the gas was partially dissolving the properly dried sealer so that it traveled into the down-stream fuel system. On opening fuel bowls and pumps, it looked more like something that should be floating around in a lava lamp ! Not long after that old fuel pumps, and rebuild kits of that era, started having diaphragm leaks. It's been over 20 years since I've talked with Tom Hannaford, at "Then and Now " (called the Antique Auto Parts Cellar back then ) about, how he had to deal with the fuel problems by finding and replacing the diaphragm material in his fuel pump rebuilding kits. I've not had any problems with his kits since he changed over to alcohol resistant diaphragms all those many years ago (same with Bill Hirsch changing his gas tank sealer from the original yellow to white alcohol resistant sealer way back then).. Paul

Alcohol has been mixed in USA gasoline since the 1980's ( as part of Jimmy Carter's national energy program). The problems for antique autos with it turned up quickly and one result was alcohol resistant gas tank sealers came out back then. Shortly there after, so did changes in fuel pump diaphragm materials,.... so it's very possible your 1990's factory pump is OK with it. Paul