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Torn accelerator pump:
Is it a leather cup on the accelerator pump or a rubber type cup???

IF it is leather then then it is probably OLD STOCK from at least 40 years ago, or more like 50 - 70 years ago and the leather has deteriorated.

As HH56 indicates a fwfew posts above, u need to try a different supplier for the acceleratr pump.

Also, check the spring under the plunger cup of the accelerator pump to be sure it is not damaged and causing the cup to tear. Sounds like u need to find a new supplier or the mechanic installing the accelerator pump is treating it too rough.

My accel pump blew out the side of it. (see my recent blog entries about this).

The cause of this was not driving it for about 9 months which caused the brass "plumb bob" like check valve between the pump and the jets to varnish in place. So with that, you're now trying to compress a liquid, and the varnish was stronger than the leather pump. So it blew out the side of the pump enough so that the leather caught on the housing and repeated pumping kept tearing it.

On my car, I could start the car, but any accel would pretty much cause it to stumble and die. While it was driving it would still stumble but not die, but from a standing stop, I had to baby it to get it rolling, or it would die.

After clearing out the varnish, and installing a new pump, it's all good. Also, you could have clogged Accel Jets which could cause the same blowout.

The pump that blew out was from Daytona, and was leather, and was about 4 years old, but only have 500 miles on it. The stuck check valve caused the blowout, not a defective pump itself.

Pull off the air cleaner, hold open the choke plate and look down to see if the accel jets are both squirting when you work the throttle.

Just to clarify on the accelerator pump, it is brand new and we now know that's not the problem. After sitting since Thursday and not having the time nor knowledge to get it running, at least to get it inside storage off it went to the mechanic again. I definitely need to learn to do more on my own.

Once it arrived there it started right up, this is after I had tried to start it before it went on the flatbed. So clearly there was a plug somewhere that worked its way loose. I doubt it was sediment or dirt in the tank that got sucked into the lines because that's all new. The sending unit failed months ago so I'm wondering if the float some how cut off the flow - though that seems strange.

Either way, the tank is getting dropped and soon I'll find out.

Alright, guess it's time for an update.

New Oldsmobile oil pump in place and the car is running fantastic. Replaced all the hoses and belts, all grease points hit and finally successfully adjusted the throttle linkage so the lockup happens at 35MPH rather than 50MPH. Though I think the two changes of ATF also helped.

Next up?

Brake light switch. I've noticed the torsion level isn't reacting and my brake lights don't work and neither does the trunk light. From what I've read on here those are good signs that the switch needs to be replaced. Little more research on my end and hopefully it'll get done before the season ends.

I'm also debating having the front doors repainted as the paint is cracking down to bare metal. My goal was just to maintain and keep as original as possible, but I also want to be sure I don't let originality come before preservation.

Oh....I should probably eventually get the gas gauge back to working order, but....priorities lol

Brake light switch is a likely possibility if only the suspension and no brake lights is the problem. If the trunk light is also inoperative and started at the same time then for 55 the body feed fuse in the block under the dash is more likely. If that fuse is blown or making poor contact in the clips there should also be more lights such as the courtesy light over the rear seat and the ones on the outside of the rear doors not working.

IMO, if you need a brake switch you would be money and reliability ahead to buy a conversion kit or build your own circuit that uses a modern inexpensive 2 terminal brake switch available everywhere rather than spend the money on another NOS 3 terminal switch. The conversion circuit is simple and needed parts are readily available.

If the courtesy lights all work and the trunk doesn't it is more likely that the switch inside the trunk light assy has oxidized. Early cars had mercury switches but by 55 there should be a steel ball that rolls to make a connection as the lid raises. Either one can oxidize or corrode the contacts. Sometimes taking the assy out and just shaking it so the ball or mercury moves vigorously will clean it up and other times it takes more work. The mercury is in a sealed glass envelope and if those contacts oxidize it requires replacement with something else. The balls can sometimes be cleaned up.

Thank you, Howard!

The other lights work, I even got the rear compartment light and map light to work by working the switches a few times to cut through the oxidizing. I guess the trunk like randomly working just happens to be a coincidence.

The torsion level will work on occasion, which must mean on occasion the switch is working. Anywho, I searched the forum but didn't find a how to on t he fix. Is there one? I definitely want to take your advice and use the conversion and not a NOS switch.

You can by a mechanical switch conversion kit ready made from Dwight Heinmuller or the hydraulic version from the Pacific Northwest Packard region and maybe Kanter too. Those will plug in but are a bit more expensive as you are paying for the convenience. I personally like the mechanical as it eliminates the issue of silicone fluid for those who like to use silicone but that kit is a bit more involved to install. A lot of purists don't like to see that conversion because of the somewhat visible bracket needed to hold the switch.

The hydraulic conversion is a very simple electrical circuit and all components are hidden. You can get a kit or buy a relay & socket from ebay for around $10 and with some wire and terminals, make your own. The brake switch is available at Napa or about any parts store for another $10 or $15. You can splice into the existing wiring directly or use .156 diameter bullet connectors to mate with the Packard 3 terminal brake switch plug and to connect to the new hydraulic brake switch.

I have info on the mechanical switch needed for that conversion but 55 and 56 brackets are different due to the shape and location of the pedal arms. I don't have the 55 dimensions so Dwight's kit would be the easy way to go unless you wanted to experiment.

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Fantastic, Howard, thank you!

After reading through the forums it seems that the mechanical switch is the preferred one for longevity. I think I'll be going that route.

I've reached out to Dwight and Pacific Northwest to better understand the installation for a 1955. I'm a total novice and want to be sure that I do this once and right.