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Tony, until you get your vacuum sorted out….
The last part of my tome on vapor lock in PASB will cover mechanical and electric fuel pumps, but I don’t have any experience with vacuum pumps, and I don’t know what the limits of pressure are for them. However, basically I have found only three 6 volt electric pumps available anymore. There are two versions of the small Airtex thumper pumps, they look to be identical except one is rated for 4-6 psi and the other 3-4 psi. I believe the higher pressure is E8011 and the lower is E8902 but you can confirm on the Airtex website. I use them for priming the carburetor mainly. I haven’t had very good luck with them. The third 6V pump is the rotary which is overkill in terms of flow and goes up to 8 psi and definitely needs a pressure regulator. They are available as both an Airtex E84259 and a Carter P4259. I have one of these on my Pierce with an adjustable Holley regulator. It initially was adjusted to near zero fuel pressure so I think it should work. I got it from Summit racing in Sparks.
Jim
Here is one that doesn’t work, a trial fitup. I installed one of these on my Packard, it is removable and replaceable with the original but is too long on my 845 Eight Pierce, the fan blade would hit it. Perhaps it could be used on other P-A models. It is Purolator A24630 and was great because it has a pretty large flow area. Back to the drawing board on the Pierce 8.
Looking at the K&N site they have one universal filter that might be adaptable for driving use by cutting the rubber universal clamp flange off and using the original Pierce end cap and screws to hold it on. It could then be swapped with the original for show by removing the two end nuts. It would stick out from the body .25″. It is K&N number RU-1850, 7.50″ OD, 6.0″ ID, 4.5″ long.
The wrap mentioned above looks like it is just to keep the big chunks out which is all the original P-A mesh filter does. It is mainly to extend the life of a finer filter under it. Neither is going to keep the fine sand particles out that are the biggest cause of wear to the ring and bore – particularly if the engine only has basic cast iron top compression rings. Engines were commonly re-rung at 15000 miles back then.
When the paper pleated air filters were introduced they were perhaps the biggest improvement to reduce ring and cylinder wear together with chrome rings. They are more effective at filtration than the oil baths that became popular in the 1930’s, but I think the main reason they weren’t adopted earlier was cars were still being driven on dirt roads and a fine mesh filter would plug too quickly. The oil bath doesn’t filter as well but can tolerate a lot more dirt.
Perhaps not authentic, but a pleated air filter will keep more of the original authentic metal in the cylinder when driven. I hate digging out the fine metal particles from the magnetic plug when I change oil.
Jim
I had the same thought, and looked through her art online to see if the Silver Arrow looking car was from one of her pieces. It doesn’t look like it, her main auto related piece being a self portrait in a Bugatti. Sex and nudes seemed to have been a bigger interest to her. Not that there’s anything wrong with that.
Jim
By coincidence I just remounted Lovejoy shocks back onto my ’35 yesterday. I don’t know if you are having the same problem on your ’31 removing the shock, but for what it is worth: It was a bit tricky as mentioned. The hole to fit the socket through to turn the nut is slightly too small to fit a standard 15/16 socket. Maybe sockets were thinner back then. When I removed them a few years ago I wasted most of an afternoon looking for different sockets trying to find one slightly thinner. I didn’t find one. I ended up slowly cutting the OD down on a socket by grinding – I used a hand grinder to cut down a 1/2″ drive 15/16 standard socket mounted in a lathe.
It needs to be a standard socket – not a deep. A deep will stick out of the hole in the frame and bind when trying to turn because of the tight clearance after grinding down to the minimum possible to keep from weakening the socket too much.
Another trick when trying to reinstall is getting the split washer onto the stud without dropping it inside the channel. My fingers aren’t long or dexterous enough. I used a short length of brass tube the diameter of the stud to push against the stud while using a larger ID PVC pipe to push the split ring onto the stud. Mount the socket on a short extension, put the nut in the socket and use the extension to push the nut onto the stud and twist by hand to get it started. This was a surpizingly awkward task.
Good luck!
Jim
Ed, do you know if the earlier ’33 design tappets interchange with my ’35 design, i.e. either style plunger can drop into the same cam follower?
Jim
Tony, I had a post a couple years ago on this message board that showed cutaways from the two basic designs from earlier PASB’s. Just do a search using tappet. Presumably a Seagraves NOS would be the ’36-38 design that was built in large numbers during WWII as they were used in a Cadillac powered tank. Egge bought up
that inventory, or so I understand.
Jim
Actually, it could be that the external spring tappet plungers like mine are interchangeable with the original internal spring ’33 design. I don’t have a’33 tappet to compare dimensions, but the diameter of the cam follower in the block is the same .688 as reported in PASB 80-5 and the action of the check valve is the same whereas the ’36-38 design is quite different with a larger bore diameter and the check valve works upside down relative to the first design, despite also having an external spring.
Jim
What is “PCS””? Jim”
The way I did it for a single tappet of course was very tedious and time consuming doing it on hobbiest lathe and mill. They could be produced professionally on a CNC, but I have no idea what it would cost. I do have CAD drawings that could be used. The tappet I replaced could be also be used for a pattern, if I take off the brass skirt I added.
One issue on getting them reproduced is how many need them? I believe mine might have been produced for only part of the 1935 model year as they don’t match the designs seen in the PASB’s for either ’33-35 or the ’36-38 design. Mine have external springs and a tapered nose but basic diameter dimensions of the first design. That was one of the reasons I decided to try and make one.
The inside diameters of the tappet follower bodies seemed to be very consistent (.500) so the plungers could probably be ground to a consistent diameter and be interchangeable (.499). The originals were also surface hardened for wear resistance, my replacement isn’t but the surface area is very large with flooding oil flow lubrication, and the side loading is virtually non-existent, so within the limited miles this engine will ever see I don’t think that is an issue. The plunger I replaced did not appear to be worn, I think it was undersized from the get-go.
Jim
This can be done theoretically with a very simple circuit using a single zener diode and one resistor. It would output constant 5 volts from an unregulated supply of more than 6 volts. The circuit must be sized for more than the maximum current draw the device will use and it will draw that current constantly as long as it is getting voltage from the car battery regardless of what the draw is from the device. If you made a circuit that doesn’t work, the first question is making sure it is wired for positive ground instead of negative.
Although less elegant, an inexpensive 6-12V volt step-up converter connected to a standard 12v to USB 5V stepdown is quicker and cheaper. A bit like FedEx packages flying from San Francisco to Los Angeles via Memphis.
I have a 6-12v step up converter to run a hidden 12V stereo that is considerably more sophisticated and efficient (You can have an authentic radio or authentic music, but not both). The step-up converter draws miniscule current when the radio is off and still delivers the tiny voltage to keep the presets in the radio. As long as I drive the car maybe once a month it doesn’t drain enough from the battery to prevent starting. I bought it on Amazon for $29 and it has 10 amp max output, can be connected to positive or negative ground ( Although anything like the negative ground radio has to be isolated from the positive ground car to keep from shorting).
Jim
David, the check is in the mail – no really! Thanks for doing this!
Jim
I have a ’35 back piece with the glass tube and capillary tube still attached. The sending unit and spring covered tube were cut off. I have a face plate that is in fairly good condition , it is still quite readable but the white is tinged brown and a little has flaked off. I don’t seem to have a bezel or glass.
Send me an email and I should be able to send a picture.
Jim
I’m not sure how to reset the cross bar – on mine I think the only option to reduce clearance is bending it in after reinstalling or putting in a larger diameter cross bar. My crossbar is just a tiny diameter pin. Actually, now I recall that when I ended up building a new seat for one of my tappets (not the current suspects) I came up with an alternative way to retain the check ball and adjust the clearance. I guess I blanked that bad experience out of my mind!
Meanwhile I am cogitating to understand what I am hearing vs what I am seeing. Listening with a stethoscope the tapping is clearest on the block near the valve seats – implying the noise comes from the valve hitting the seat at a higher velocity. This implies it is coming from the lifter leaking down while it is pushing the valve up and the valve is hitting the seat harder because it is ahead of the deceleration part of the cam. The tapping clearly goes away increasing RPM above ~1000.
Without thinking about it, I originally expected the noise to be more easily detectable on the tappet blocks with the idea the noise is from having valve lash and it is coming from the cam hitting the tappet or the tappet hitting the valve stem as in a mechanical tappet with lash.
Has anyone noted with a stethoscope whether their tapping seemed to be closer to the valve seat or closer to the the tappets? I haven’t really thought it through but it might be relevant to diagnosing whether a tappet’s problem is from a leaking check valve, too much bore clearance, or too much clearance between the cross bar and the ball.
I am thinking about an alternative test for leakdown, and will probably end up replacing the balls and lapping the seats. I will check the clearance between checkballs and crossbars as well. Not keen to press those tiny crossbars out!
Thanks, Jim
Thanks, I got the lifter block out. I am trying to get the engine and drivetrain working well before doing the bodywork, so I am hoping to get it quiet before resorting to STP or thick oil. I don’t have any fenders or hood on the car so it is easy to see and get to them now. I tried something else that worked okay. After getting the lifter block loose and tilted out from under the valve stems and still resting at an angle on the cam I pulled each tappet out of its cam follower bore, keeping each one in its own marked bag to keep from getting them mixed up. I screwed short bolts and washers into a short piece of rubber fuel line that created a bit of a taper fit and I jammed them into each cam follower bore. That had enough tension to keep the bolt and washer attached to the cam followers preventing them from dropping out of the block as I pulled it out of the engine.
When the engine was running there was a lot more oil coming out of #11 and 12, and much less out of #9. Now that they are out I did a quick test to see if 11 or 12 seemed to be obviously leaking more than 9 using the bubble test described by the factory in the PASB’s. Nothing very definitive. I had already done a lot of cleaning and bubble testing when I assembled the engine a year and a half ago and had lapped the seat and replaced the check balls on a couple. Will do more diagnosis next weekend.
Jim
Keeping enthusiasm up to finish is very difficult. The amount of time and treasure huge and impossible to justify practically, particularly if the car is worth a lot more in parts than whole. The “eating the elephant by taking one bite at a time” metaphor being apropos. Being a rare and very desirable body style Richard’s car likely is worth enough to pay back the investment in money if not time.
A friend of mine lost all ambition years ago after paying for poor machine shop work from supposed experts. He is disillusioned about having any work done by “professionals”. He has piles of multiple cars torn down.
Personally I am always at the edge of that point – when I did my Packard 30 years ago part of what kept me going was the people who saw the pile of rusty parts too polite to say what they are thinking – this guy will never finish this. That kept me going as much as anything. Having proved it once on a rougher car, I don’t have that incentive on my P-A.
Jim
I was heavily influenced by the Virgil Exner ’66 Classic revival series, particularly the P-A and they were a big factor of in my interest in mid ’30’s Classics. Most of them were in my view quite ugly when you got to the full model as opposed to the basic side views of the picture on the box. The ’66 Pierce looked great to me from all angles. The ’66 Bugatti was the also very good looking and I finally found one of those models unbuilt a few years ago. I have the remains of a ’66 P-A kit I built in the 60’s and an unbuilt kit I found on Ebay a few years ago.
I once scaled the measurements of the P-A and found it would have been about 22′ long for what amounts to a 4 seat club sedan!
I have had idle thoughts at times that a mid ’70’s Datsun 240 or 280Z could be modified into smaller reasonable facsimile that could be a pretty nice car.
Jim
Sorry one more item to add, but this come from total ignorance on ’29 carburetors. If there is a “power booster” or “economizer” valve that opens at high throttle – it possibly could be stuck open or otherwise messed up or misadjusted. That valve opens to richen the mixture quite significantly on the order of 10/1 air/fuel for maximum power. That is rich enough to generate soot but the car would run smoothly without any obvious problems like missing.
Unless everything is just plain worn evenly, I would expect broken oil rings or stuck compression rings passing oil to leave plugs with much bigger buildups on some but not others. The buildup on the plugs would probably be uneven compared to rich mixture that would be evenly deposited and more powdery looking.
Burning oil exhaust tends to be a bit blue rather than pure black. As long as the engine is firing evenly ignition advance or retard is a weak influence. If the car is running smoothly without any misses and the exhaust is black, it is most likely rich mixture.
Jim
David, I will have the same problem on my ’35 club rear vents. Put me down for 15 feet.
Thanks!
Jim
There are several tings that can cause too rich a mixture. One is just plain starting and stopping the engine for very short periods without it warming up. Just running it long enough to move it in our out of the garage or around the block instead of driving several miles will build the carbon up.
Another is the choke pulled partially closed or misadjusted. It should be wide open after the engine is warmed up. Another is running without a thermostat (if equipped) or the radiator shutters (if equipped with temperature controlled shutters)are forced open. These items keep the engine from ever warming up in cool temperatures or extend the time it takes to warm up in hot temperatures. I was constantly fouling plugs on a car that I liked to drive around before I had the grille shutters installed that let it warm up.
Carburetor float level too high or float leaking and sinking, or float valve not sealing. Fuel pressure from an auxiliary electric fuel pump too high and overpowering the float valve.
I would check these things before carb jets.
Good luck, Jim
Jim
On evaporative coolers, I believe they appeared much earlier – in the 1930’s at least. A childhood memory of my mentor was cutting his finger on the fan of a window mounted evaporative cooler that his father rented when they moved from the Midwest to California in the late ’30’s, so apparently there were more expensive units with fans that would move air when stopped. Window units had small water tanks in them, but adding ice would reduce the temp for a while (melting ice as about 15% of the cooling effect of evaporating the water).
I am not concerned with adding any holes though the firewall of my Packard or Pierce, they already had them. Both were already cut very crudely presumably by the dealer or perhaps the original owners themselves to plumb aftermarket heaters. In the case of my Packard they cut through a corner of the data plate. Now in terms of originality what counts, the crude hole cut by the original owner to make the car more comfortable, or trying to cover the evidence. Who counts more, the factory as originally delivered, the original owner who actually used the car, or the person who spent a lot more time and money than either resurrecting the beast?
I’m not posing the question in terms of judging, since that is not something I participate in. I admire the skills, time and patience that others have that I don’t to do better than new restorations but my interest is more about the genius of engineering and manufacture that went into these cars. I think we put individual cars on too high a pedestal. An extreme and unrealistic ideal of these cars when new and never touched by an owner seems to be the goal of judging. Of course it would be impossible to set guidelines for some other arbitrary standard, so in the end it is to each his own.
Jim
