Packard Forum Index » Pre-War (1899-1942)

Hi guys,
I want to lubricate my wipers as I don,t think they've been done for a while and are starting to get slow. I plan on using neatsfoot oil, is this correct? What is the best way to get the oil into the works? Do I have to take the wiper to pieces?
Thanks
Terry

Your vintage wipers probably have leather seals on the paddles (if they haven't been updated) so Neatsfoot oil would be a good choice. Also a good vacuum motor oil like Mobil's is a good choice.

I've never had occasion to work on the ones on my 34 and they still work like gangbusters so no advice on how to administer the lubricant but the same method used on the postwar Trico motors and described somewhere on this site might work well although the wipers are mounted very high above the windscreen. A couple of screws on the fascia panel above the windscreen and the motors are right in front of you - you might consider just taking them off and cleaning and oiling, it would give you an opportunity to replace that 80 year-old rubber vacuum tubing at the same time.

Also, if they've slowed down you might check the vacuum booster pump, and also look for vacuum leaks. The most common point of vacuum leaks is the Bragg-Kliesrath power brake control valve and cylinder, and the Stromberg automatic choke gasket. Another candidate would be the vacuum pump in the Bijur. New diaphragms and seals for the power brake unit are available from Classic & Exotic.

Good point Dave, never thought of that. What should the vacuum value be and where would one test it? How do you isolate the brake vacuum from the bijur vacuum?.

Cheers dave

Terry

Terry, an engine with rings and valves in good condition should give a manifold vacuum reading at idle of 18-20 inches, and the reading should be quite steady.

The main vacuum take-off at the manifold is hard-piped to the rear of the block, passenger side, where there is a fitting and it splits into two lines. The smaller, lower (nickel-plated) line goes tothe vacuum booster pump, the larger line changes over to rubber hose which crosses the back of the block and emerges near the starter motor where it changes back to hard pipe up to the power brake variable boost valve and then on to the brake control valve (under the brake pedal and power cylinder, There is a take off from a hard line at the inlet to the power brake variable valve that feeds the Bijur. Thus the vacuum booster pump on the fuel pump is only for the wipers as the brakes and Bijur don't need boost because the brakes are never applied while the engine is under hard accleration.

Problem is, there really is no convenient take-off to install a vacuum gauge. Though you could jury rig something, I think the easiest initial test is to, one by one, disconnect the Bijur, the Stromberg automatic choke, and the line to the brake system, hold your finger over the end, and see if the engine idle suddenly increases. If so, that would be the source of the vacuum leak.

Perhaps someone else with a 33/34 will see an easy place to hook up a vacuum gauge, the only possibility I see is a removeable plug at the inlet side of the brake variable valve, but it's a very small diameter so you'd still have to jury-rig some sort of take-off for the gauge.

When I mentioned earlier the most likely source of vacuum leaks (brake system and fuel pump booster), I should have also added the large diameter rubber hose that runs behind the engine block; if it's 80 years old, time to replace it.

Let us hear your findings.

At least some points to start on. I will report back as soon as I get the car back from having some minor paint work done. In the meantime I will go to classic and exotic and check out the parts.

Hi guys,
At last an update on this problem. I took Daves advice and checked the vacuum reading and took it at the connection point on the inlet manifold side of the variable vacuum boost valve where the Bijur connection is.

This proved a good healthy reading within Daves readings of 16- 20 inches. I then checked the vacuum boost valve diapraham and this proved to be in poor condition and I replaced it. From there I then changed the brake valve and booster canister parts.

With high hopes I turned on the wipers but to no avail the drivers side still didn't work properly which is strange as Fickens rebuilt it about a year ago and it worked when replaced in the car. The passenger side although a bit slow works ok.

This beginning to bug me as you all are probably aware it rains quite a lot here in the UK and to have no wipers on the drivers side is a PITA to say the least.

Iam not quite sure what to do next as I am unsure of anything on the fuel pump part of this mystery. The fuel is obviously being pumped by the pump as I have had no trouble with the car starting and running so what part does it play in the wipers. I was not quite sure on what you meant Dave.Quote(Thus the vacuum booster pump on the fuel pump is only for wipers)
I see that on the fuel pump there are two connections one goes around over the top of the on the back of the engine and the othe to the wiper line (I think)
Further help required please. By the way I haven't yet got around to replacing any hoses could this be the problem?

Thanks for looking

Terry

Terry, let me try to clarify. There are two systems on your car which are operated or assisted by engine vacuum, the windscreen wipers and the power brake booster system. Engine vacuum is at it's lowest during engine acceleration or heavy load; this would decrease the performance of the wipers and thus the wipers have a secondary source of vacuum, the vacuum pump which is part of your fuel pump (it's a two-section pump, one for fuel and one for vacuum,both using a rubber diaphram and valves). The vacuum booster section of the fuel pump is not connected to the vacuum power brakes because it's not needed - you don't apply the brakes at the same time you are accelerating, or at least I hope not, and manifold vacuum is at it's highest during decelleration.

So...if only one of the two wiper motors doesn't perform properly as you indicate, it's probably either the motor itself or the rubber hose and/or connections that connects it to the vacuum source. If the wipers slow down significantly (or nearly stop) when you accelerate heavily, then the vacuum booster section of the fuel pump needs rebuilding. With the wiper system operating properly, even under the hardest of acceleration the wipers should just barely slow down - almost not noticeable. I've never replaced the wiper vacuum hoses on my 34, but that doesn't mean yours are still intact - inspect them or just change them. Rebuilding the vacuum section of the fuel pump is essentially the same as rebuilding the fuel section, pretty simple basic stuff.

Another thought has just occured to me as I type this; the two vacuum wiper motors are in series with the one on the right side being the end of the line. So perhaps, if you have a vacuum leak anywhere (and especially think of the booster diaphram in the fuel pump), perhaps it's possible that there is sufficient vacuum to operate the first motor in the series, but insufficient residual vacuum left for the second one and thus the problem may not be the wiper motor itself as I had suggested above. Again, suspects would be the hoses and connections, and the fuel pump vacuum booster section. If you haven't rebuild the vacuum section of the fuel pump within the last 10 years, I suspect it's time for it now.

Keep us posted, please.

Cheers Dave,

That explanation sure does clarify things. I will report back at some time hopefully not in the too far distant future but the weather is getting rather cold now to work comfortably in the garage.

Here's wishing you a merry xamas and happy new year which also goes to all our friends on PINFO

Terry