Misprint in parts manual. 5.1202 states that 6492431 is the part number for all 55th pump bodies. 6492430 is the casting number on the very late oil pump body. 6492431 (one number greater, according to Packard practice) is for all 56th oil pumps. I have 6480508 as the latest oil pump assembly written in my parts book but cannot remember where I got that number. It has to be SC or TSB.

I only got 88%. Guess I'm slipping

Just for fun, here's a link to a site where you can test your mechanical aptitude:

http://www.forddoctorsdts.com/quizzes/MechanicalAptitude.php

It takes a little time to load if you're on dial-up (like me), but worth it.

I buzzed through it and scored 92%. If I had been a little more careful, I would have gotten 96%.

To the best of my knowledge the spring never was part of that kit - even in the original Bendix package. Again, neither was the plunger/piston. However, such additional parts were available, separately, from dealers and parts stores alike (back in the day).

It seems to me that the minor kit was intentded for replacing the components that were most likely to wear out and leak (and those sacrificed in getting at them). Again, I doubt if Bendix or any of the automakers anticipated their vehicles being in use half a century later, and the damage caused by moisture entering the hydraulic system occurs over a long period of time.

Strange that the compensator port spring is not included in the kits.

Peter -

Many vehicles of that era used the TreadleVac system, including highly-popular cars like the 55-56-57 Chevy - not just Packard. If there was a genuine design problem with it, something would have been published long ago. While I doubt that anyone involved in design and production of those automobiles and their component parts (back then) ever envisioned people driving them so many decades later, those old cars were (thankfully) built to be renewable. Yet, some people may not fully understand what they're working on, and people tend to fear (or even oppose) what they don't understand.

In that regard, know that Bendix offered TWO levels of overhaul kits - minor and major = throughthe after market (as well as the aftermarket).

The minor kit contained only those parts that were required to rebuild the hydraulic section; everything you need to upgrade the T-V master cylinder to DOT5 is in that kit. That kit was reproduced decades ago and remains widely available today, and I prefer fresh rubber parts to 50+ year old NOS ones (provided they are of sufficient quality). Attached is a pic I snagged from Kanter's site (www.kanter.com/p08-bk.html), showing the contents of that (minor) overhaul kit. Notice that it includes a new compensator port valve, but NOT the fine-wire spring.

The major overhaul kit included the additional parts that were needed to overhaul both the hydraulic and vacuum sections, but I'm not sure if it included the compensator valve spring. I do have an NOS major kit somewhere (not for sale) in offsite storgae; if I can ever get time and can lay my hands on it, I will take a pic, inventory the contents, and report back here.

Now, anyone smart enough to take one of these units apart and put it back together would notice something like a pitted hydraulic plunger/piston, but it was not included in either of the kits - had to be purchased separately.

Yet, my point is that the compensator port valve spring is one of those things that is often overlooked - especially by those who do not understand its purpose and function. The 1955-56 Packard Service Manual explains the TreadleVac operation better than the "restorograph" sheet included with some overhaul kits. With a little patience, operation of that valve can be checked with the unit still in the car. The reservoir cover can usually be removed without ruining the gasket, though you might have to remove some fluid from the reservoir to see it. Also, during a rebuild, one should inspect this spring for corrosion as the spring will break in that point.

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Well I finished cleaning the steering kunckles. So clean now you can actually read the part numbers on them. I got the backplates taken down to bare metal, primed, and painted.

One question I have is that there are two gaskets (or seals) 15.4045 & 15.4072 (on this plate) that are used on spindle/backing plate. Does any one have a part number cross reference to these? I could probably find a match for 15.4045 if I took it into Napa as they came out in one piece, but 15.4072 came apart in pieces.

I use my air compressor. I did the test with the switch not installed in the brake line. I just screw the 1/8" threaded male sw conn into the air gun I use for blowing away dirt, etc. connect a ohmmeter or conductivity light to the common and N/C contacts and then adjust the pressure until the switch activates.
I found the wells RB402 brake switch will activate the N/C T/L contacts at about 38 to 40 psig, causing them to become open. I then connected the wires to the switch, 12v (pink) to common (center term), LT Grn to right term, Dk Grn to left term. I then presured to 40 psig, thereby killing power to the T/L switch. I figured the other terminal contacts for the brake lights should activate at the same pressure, but there was no change "no power to DK. Green wire to the brake lights", so I increased the pressure incremetally "about 5lbs at a time, didn't want to blow the diaphragm" until I reached 70 or 75 lbs, still no power to the dk grn wire. I moved all 3 wires to different terminals but, I never could get term 3 (left)to change status with the common or the N/C term which makes me believe the switch is faulty. I don't know how they calculate the pressure it takes to stop the vehicle but, I'm sure the equation includes mechanical aspects such as shoe or rotor size,etc. Anyway, I'll check it when I get the new switch and let you know the results.

Good point Peter, it is only 12V, as I'm basing it off of a '70s Pontiac distributor.

G'day Eric, Is this a conversion for 12V only or is it able to be adapted for 6V systems. Best regards Peter Toet