Packard Forum Index » V-8 (1955-56)

Thanks for all of the advice guys, I certainly appreciate it. Now, if I come across as being a little pissed off with what is happening, that's because I am! Today I thought I'd follow Brian's suggestion about testing for vacuum leaks by taking the car for a 6 mile run as is, and then again over the same route with the vac tank isolated from the system.

Before starting out I decided to check the brake adjustment, just in case. It was done before the short test run after switching over the front drums and shoes, but not since. Surprisingly, the right wheel was reasonably hard to turn while the left spun pretty freely. I had done them both the same, backing off 12 clicks. After backing the right off a further 12 clicks, it was turning more freely, but certainly not ideal. OK, doesn't sound right but what the heck, let's go on that 6 mile run. Car seemed to drive OK, pulled up pretty evenly, so I started to think everything was hunky dory. Big mistake! After returning to the shed I decided to check the adjustment once more. The left was like before but the right, the bloody right, was now very hard to turn forwards and fractionally easier backwards, much worse than it was before I backed it off. At this point I gave up in frustration (and a torrent of invective) and walked away. It maybe a sticking wheel cylinder, who knows. On Sunday I'll take it all apart again to see if there's anything obvious. Testing the wheel cylinder while still attached might be a problem(??). Vacuum testing will just have to wait until this is sorted.

Now, on a different topic Packard V8 suggested raising the idling speed in summer to keep the generator spinning to provide more current, and I'll look into that. I have tried to keep the idle speed as low as practicable (about 550 rpm in neutral) as the TU likes to jump into reverse when selected, and more so when the revs are up. I have read on another post that this not uncommon and that the severity of engagement can be toned down by making a small internal modification that slows down oil flow. I don't want to fiddle with the tranny but have become aware of a specialist over here that knows something about TU's. I'm going to get him to service it for me soon and will ask him whether he can do the mod for me at the same time. Anybody else tried this? Regards, John

JP -

Sounds like you're saying that the pull has now moved from left to right - as you had expected previously.

Among all the work cited in your opening post, you advised that the wheel cylinders had been reconditioned. By that, I assume you mean the originals were honed and the seals and springs replaced. Also, kinda doubtful if its a sticking wheel cylinder, then, since you did not swap those L-R.

Yet, did you replace the brake shoe springs, and if so, are they oriented correctly - primary vs. secondary?

If you're gonna take things apart again, the first thing I'd check is for twist in any of the shoes. Simply lay each on a surface plate (a table saw is a good substitute) and see if they lay flat.

WRT to chasing vacuum leaks, if the tank proves to be sound, you'll need to check downstream. You might wanna test drive with the primary feed for the wipers blocked off, as that's fed off the same port as the power brake check valve.

As for your TU, you might wanna look at Ross Miller's thread on Things that go bump--in reverse wich involves a mod for harsh engagement.

Quote:

Might be a problem?? -- yes. If three cylinders are restrained and one isn't, guess which gets all the fluid. Needs a helper with a light touch on the pedal. I found the hard way there's a very small margin before a piston is out one end and fluid is on the floor.

Any chance the R front hose could have swelled or disintegrated internally and is causing the issue? Any sign of mashed tubing in that length in front of engine?

As to the reverse mod, I did it but with limited driving so far, honestly can't say I notice an appreciable difference. I made the plate using an old valve body for fitting so I'll concede that perhaps there is a difference in angle & maybe I didn't get the plate close enough to the port on the real car.

My 2 cents worth, and I'll admit I haven't been following this thread carefully.

Don't adjust brakes by click-count, adjust by feel. A good starting point is just a hint of drag of the shoes, you hear it more than feel it, as you rotate the wheel forward.

Don't increase idle speed on an Ultramatic car to 800 rpm, keep it in the factory spec range, more or less 450-500. Increasing it to 800 rpm for a bit of charging and more cooling for the few minutes you're at idle is, IMO, folly. Unless you're going to idle for hours at a time with a large electric drain like a police car at an accident scene, you don't need a positive charging rate for the few minutes you're at idle. And unless you're in a really stressful situation, a few minutes at idle isn't going to have much affect on engine temperature - and if it does, put in neutral and feed a little gas until it's time to resume driving. The V8 models have very competent cooling systems; unless you're in extreme situations like Kevin in AZ sometimes finds himself, you should be able to tolerate most any condition. And if you really need more cooling, a higher volume fan is the easiest first thing to do, assuming a cooling system in good condition.

Thanks for the advice guys. First the cooling and yes, the system is in good order. Less than 12 months ago I had the radiator professionally cleaned and a small leak re-soldered, and it came up good on the pressure test. It is, I was told by the previous owner, a genuine factory heavy duty radiator for air conditioned cars. I also fitted a reconditioned water pump and new hoses, and it doesn't run hot. I've also wired in a pusher fan to come on automatically when the A/C is switched on, or separately from the A/C if needs be. I would be happy to fit a higher volume engine fan if I knew what to look for - all that I've seen so far don't have a centre hole big enough.

Now for the brakes. I've been doing a bit of thinking on this and I think I've almost convinced myself that the problem is a sticking/stuck wheel cylinder. I agree that the number of clicks for adjustment is just the starting point that that the easy spin with light scrape is the fine tuning. However, with the right brake it is always a heavy scrape and at the moment, close to lockup. The more I think about it, the strong pull to the left I was experiencing could well be the left brake working and the right doing bugger all. My switching them over may have caused the right wheel cylinder to move a bit before sticking again. If this is what's happening, this might also explain the heavy pedal with most braking being done by one wheel.

That's all theory for now and I certainly have to dig deep inside to find the source of the problem. If it is the wheel cylinder I won't be very happy as they were professionally reconditioned about two years ago with stainless steel liners in the bores, supposedly to last for donkey's years. However, if it turns out that this is the problem then I'll source two new ones and replace them both. What and from where will be an issue, but I know the brand, part numbers, etc, so hopefully someone will be able to cross reference them to something available locally. If not, then I'll have to check out what's available in the US. I'll keep you posted. Regards, John

Not so fast on ordering the wheel cylinders. First take the offending wheel cylinder apart and inspect it to see what the problem is. COuld be crud that has worked it's way into the wheel cylinder or even the hose. Crud that has come out of the old brake line.

If the wheel cylinder is plugged or full of crud but otherwise appears to be good then u mite be in for a brake line replcacement. If brake lines are full of crud then new wheel cylinders will not do any good.

Could be a faulty brake hose. Just because the hose is new doesn't make it exempt from from internal or external failure.

G'day Guys. Firstly thanks for all of the advice. Even though I mightn't mention each piece, I do take notice and try to remember it all. You fellas have done this all before and I really appreciate the benefit of your experience.

Now to that bloody wheel cylinder. I've just taken it off and pulled it apart and possibly found what was causing the problem. Even if it wasn't, that's an issue that shouldn't be there anyway. I'll explain what I'm talking about and also attach a pic. One of the pistons has significant wear on one corner and it is also raised to the extent that it most likely would have been dragging in the bore. It's quite obvious to touch but maybe doesn't show as much in the pic. The next interesting thing I noticed is that, to me at least, there doesn't appear to be any stainless bore liner fitted as I was lead to believe, although there are obvious hone marks. Lastly, I blew the fluid remaining in the hose out onto white paper and it looked pretty clean to me.

As I'm thinking now, I really only have two options - go back to the wheel cylinder reconditioner and complain bitterly, or cut my losses and buy a new set. Preferring the quiet life, I'm thinking new ones all round would be the better option. Now to find them, and I'll start making enquiries tomorrow. Regards, John

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Check the X-ref available here at this forum. Look thru the ENTIRE list for brakes.

https://packardinfo.com/xoops/html/modules/parts/

Note that the aftermarket part numbers are often shared by various manufacturer's. So a 33005 wheel cylinder very likely will be the same number and wheel cylinder between Bendix, Federal mogul etc. etc. In many cases also the part number is shared across a variety of parts store chains.

I sincerely doubt that the Packard wheel cylinders are Packard SPECIFIC but rather fit a large variety of other automobiles, especial GM but probably F and C among others from late 1930's up thru 1980's and maybe even todate 2012..

Side note:

If the bore of the wheel cylinder is even just fair condition then REBUILD IT YOURSELF!!!! U probably only need new pistons. Rob them from some other wheel cylinders.

Or to put it another way:
ANY car OWNER can do a better butcher job than any of the qualified, sanctified, christened and confirmed, dyed in the wool "professionals".

If you have NAPA near you, then buy new NAPA wheel cylinders all the way around. $36.00 did my 56 Patrician.