The Stovebolt Site Forums The Shop Area General Truck Talk Wiper motor for 56

I had to use my wipers for the first time yesterday, and they only moved about a quarter of the way then stopped. I could park them, then start them again, with the same results. So my question is what are the pros and cons with either repairing the vacuum motor or switching it out for electric? And who offers rebuilding for the vacuum motors? I have not done any troubleshooting to see if the problem lies somewhere else yet, hopefully next week I'll be able to start on that.
Thanks, Lee.

Take the motor apart and clean and lube the moving parts and it should work fine. Extend the vacuum line so you can test it before reinstalling...what do you have to lose?

Mike B

I'll give it a try, I much prefer repairing stuff to replacing.

Often they quit working properly due to sludge buildup inside the flapper box creating excessive resistance. They can also leak from deteriorated gaskets. Replacement gaskets can be found for pretty cheap, I am not sure on your "new" model. I use a very light grease to lubricate the flapper. You will have to make your own wrench to remove the screws, like below.

[img]http://www.surfacezero.com/g503/data/3176/2014-03-07_19_34_15.jpg[/img]

Well, I opened it up, cleaned and regreased the flapper, and in the process, broke both gaskets. Does anyone make an overhaul kit for these units?

Oh, and when I reinstalled it, it ran fine, just couldn't stop it! I guess I have an adjustment issue that should be easy to fix.

I put a fuel/vacuum pump on mine.

Replacement gaskets are available. The Trico motors were used in all makes. I think I got mine from Snyder's...for a model A ford. Just carefully inspect the gasket image and compare to yours. Rebuild internals are difficult to come by. You're getting there...

Lee, here's another thought while you have it out. Even if you get it working perfectly, the vacuum wipers will always be lacking. When the vacuum wipers on my '57 began acting up a few months ago doing the same thing as yours, I decided to check a couple junkyards looking for the factory optional electric wiper motor instead of trying to fix the vacuum unit. The electric version was available as a factory option for the Task Force Chevys and I think that it was standard for the Blue Chip GMC's. Maybe I got lucky, but I found two in the first yard I checked, one out of a GMC and one out of a Chevy. Both worked fine. Bought them for $10 apiece. I figured I'd buy both so that I could have a spare.

They connect to the dash and the wiper arm assembly using the exact same hardware, bolts, brackets and cable knob as the vacuum unit.

The factory units were two speed...slow and almost fast enough...and self-seating.

The cable knob that operates the switch is the same as the vacuum unit. As you turn the knob, the cable moves the slider switch on the motor. A partial turn activates the motor to slow and a more complete turn moves the switch to fast.

Wiring is easy. It is designed to have the + wire always hot and the switch works on the - side of the circuit. Bolting it to the dash handles the - side, just make sure that the metal is clean. The factory connection to the + side was to run a wire through a grommet in the firewall and connect it to the ignition switch side of the ballast resistor on the firewall. That simple! Wiring it that way allows it to operate only when the ignition switch is turned on. I ran mine through a fuse block, but the stock factory installation did not include a fuse block.

Sharing only as an alternative. I am much happier with the electric wipers and I was able to keep things factory. It's not much fun to work under the dash, so I thought I would mention this just in case you want to consider it as compared to fixing the vacuum unit.

Matt

Thanks for the idea Matt, I would not mind replacing the vacuum with an electric. I'll have to check out the local junk yards and see what I can find. My plan is to put rain ex on the windscreen so I won't have to rely on the wipers!

Heads Up there are differences in the TF truck wiper setups...

Electric Motors:

55/56 use the same electric motor 5047909

57 is a one year electric motor 5047989

58/59 use the same electric motor 5044306

Link Assembly (arms that connect to the motor).

55-57 are the same Link L 3730483, R 3722488

58/59 are the same Link L 3750121, R3750122

Control Switch:

55-57 use a cable driven control switch for the electric motor 3739691

55-58 use a cable driven control switch for the vacuum motor 3737827

NOTE; the cables are different lengths between the electric [long] and vacuum [short] setups.

58/59 use an electric switch 1998657

Mike B

Thanks Mike for the breakdown on part numbers; I have a 56 so now I know which number to look for.

Lee.

For what it is worth,Maybellene, that same electric wiper motor fits in the 54-55.5 cabs as well. I've done two installs and haven't looked back.MikeB Thanks for posting those p/n's and years. Good to have as a reference for others.

Did you have the original 1954 radio and, more importantly, did you have the 1954 speaker/plate when you installed the 56 or later electric wiper motor?

No...didn't have radio or speaker...I gather you are wondering about clearance, I don't know since I don't have an idea how much space is taken up by the speaker and radio. I could give you a couple of wiper motor to back of dash reference measurements...if that would help.

The original 54 speaker interferes with all known wiper motors (after market or other years or even 54/55 GMC), except for the factory 54/55st Chevrolet truck optional electic wiper motor.

Yes, the vacuum motor is easy to repair, but if you intend to drive in any amount of rain, and can find the electric motor by all means
install the electric motor. I got the electric motor out of a 57 Chev and it was a bolt in. The motor is actuated with the original wiper selector
cable.
Bob

My Trico failed in my 55.1 this year. So, I pulled it out and rebuilt it twice before giving up and getting an electric. Now, I wonder why I messed around with it. Should have just gone for the electric in the first place.

Got mine from Southwest Classics in Arlington, TEXAS.

Jeffry,

6v or 12v?

Do you have an original-style 54/55st radio speaker in your truck?