Packard Forum Index » V-8 (1955-56)

Greetings from Idaho,
My newly acquired 1955 400 wipers don't work and I'm following up on a rumor that 1955-56 chevy wiper motors are good replacements.
The vacuum system has been modified in a way that I don't quite understand - all I know is there is no vacuum hose to the distributor, brake pedal needs a lot of foot pressure (car does stop satisfactorily) to activate the braking system.
I understand that the wipers on the 55-56 series never worked well.
Any and all help will be greatly appreciated..
Thanks,
Mack

The distributor should have a metal tube connecting the vacuum advance to a port located toward the front on the passenger side of the carburetor.

The brakes and wipers should be supplied via a tee connected to a large port on the rear of the carb. Brake hose is slightly under 3/8" and connects thru a check valve at the tee. The primary vacuum and wiper supply is a 1/4 metal tube which goes toward the rear of the engine and then connects to a short rubber hose which then connects into one of the side ports on the balance valve.

Assuming the car has not been modified with one of the oil pump changes, the other side port on the balance valve normally connects via another short length of hose to a metal tube which drops down and runs along the block to a port just above the oil pan about in the middle of the block. That port is the connection to the aux vacuum pump inside the crankcase and also has a check valve -- this one is positioned just after the elbow into the block and before connecting to the metal tube. If the oil pump has had one of the conversions that gets rid of the crankcase vacuum pump then it is hard to say what could have been done to the vacuum routings. There was no real standard. Some times the aux tubing is totally gone and other times it was just blocked off to prevent a vacuum leak. You might investigate your situation and see if there is some kind of leak.

The balance valve is there to direct the strongest vacuum supply to the wiper motor. If manifold drops and crankcase is stronger it switches inputs and if manifold is stronger as it usually is, the crankcase is secondary. Wiper motor is the port on the larger end and windshield washer connects to the port on the smaller end.

If the wiper motor is in good condition it works very well but after so many years it could be worn or dried out and in need of a rebuild. Wipermanrebuildingtricowipers.com can make them work like new for not a huge outlay and a fairly fast turnaround. Unless you already have a Chevy motor or the Newport Electric motor kit a rebuild would be much less expensive than the cost of any electric conversion. The Chevy motor will bolt in but is rather bulky. The Newport will also bolt in but it requires a switch conversion which mean changing out the original assy. In order to make the new switch look correct in the dash it means destroying the old switch to get a part to cover over an empty space. If you have a windshield washer, neither electric will accept the co-ordinator without some extra work. The Chevy requires finding a not often seen cast piece for the motor attachment and the Newport requires even more work.

Brakes should require almost no foot pressure. The sensitivity is sometimes an issue in fact as many are used to longer pedal travel on modern cars before the brakes start to be applied. On the Treadlevac, if adjusted and working properly it only takes light pressure and barely an inch of travel before you risk getting up close and personal with the windshield. Check for leaks in hoses or in the vacuum reservoir under the left fender and also make sure the check valve is functioning so the vacuum cannot bleed off and there is a reserve of vacuum at all times.

You can run vacuum directly to the wipers and see if they work. You can lube the wipers and they will sometimes "recover", there are instructions here:

Winshield Wiper maintenance

I found my wipers worked better if I plugged the outlet to the washer pump, could be that valve is leaking.

Quote:

These instructions mention the use of "Trico Zero-mix Oil." Does anyone know of a modern equivalent to that lubricant?

I believe ordinary vacuum pump oil has been suggested. You want something light and refined that is not going to get sticky or leave a residue. The lube may or may not help. If the leather or compressed felt seals on the paddle sides have worn and can no longer make tight contact with the sides of the motor case to provide a good seal the lube will do very little and a rebuild will be necessary.

I looked around and I saw light machine oil and neatsfoot oil both recommended, as well as vacuum pump oil, ATF, various mixtures of things. Ford recommended light machine oil back in 1932:

1932 Ford Servicing the Windshield Wiper

Thanks. I'll give the vacuum pump oil a try.

Thank you everyone for your input. I now have my marching orders.