Chasing a 504 wiper motor

[Pug72]

Hi all

My wiper motor has been blowing a fuse for a while now. I replaced the switch on the dash, checked all the wiring, but still blows fuse. The motor really struggles to get the wiper arms up to the vertical position, then it blows the fuse. Everything works fine when I have the wipers off the glass with zero resistance.

I have checked over all the wiring and can not fault it. This is a totally original car (1972) with nothing butchered/altered.

Can I buy a wiper motor new and if so where from? I am also chasing an interior light cover (on b pillar).

I have tried Pugwreck...but am not getting any response (either email or phone)

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Thanks

[alpine]

there are 2 different types , if you can email me a photo of yours i probably have a s/h one in ACT

check your switch , could be that , I do have s/h one one of those too

Cheers

[Pug72]

Thanks heaps for the reply. Checked the switch and I even replaced it to try and narrow down the source of the problem.

Will take a picture tonight...

Thanks

there are 2 different types , if you can email me a photo of yours i probably have a s/h one in ACT

check your switch , could be that , I do have s/h one one of those too

Cheers

[neil s]

You 72 wipers are doing well! My 72 wiper motor only lasted until 1980. I seem to recall that an auto electrician put new brushes in it. Neil

[Beano]

Old motors do not cause fuses to blow.
The problem is probably that the physical linkages have frozen up. In fact, I can almost guarantee it. The grease in them gets old and dry. The strain of the motor trying to move them is what causes the fuse to blow.

You need to lubricate 2 areas :

1) The bush where the shaft comes out of the motor. It is as if there is a sleeve there and the fit is very tight because the grease has dried. This area is the prime suspect....mine was very dry and stiff.

and

2) the linkages underneath your dash....inside the car. Oh, what fun it is to get upside-down underneath your dash with a torch ! Great for the back !

For a very quick temporary fix, spray WD40 on these areas. You will however need to properly grease it within a month or so. WD40 dries out.

Having said all this, you may eventually need to get a new motor. Straining motors cause arcing between the brushes and the armature, pitting the armature, and you can never really fix that. The same happens with old starter motors. Some people turn down starter armatures on a lathe (after all, they are only copper), but an auto electrician told me that it is never really successful if they are badly pitted.

Having said all THAT, you could take apart your motor (if you are familiar or confident with them), and check the armature (isn't the copper bit the commutator ?). You can carefully scrape between the slots to clean out old graphite and then polish the copper contacts in a radial fashion (linishing) with very fine sandpaper....this is what I myself would do. If you did this, you could properly lubricate where the shaft comes out.

There aren't too many 504s left in Brisbane ! ( I have a 505, and there aren't too many of them either). What colour is your car, and which suburb do you live in, Pug72 ? I may have seen or met you.

[kelpiebat]

May have a good used wiper motor from a 73 504 Ti. Transport would be OK with my truckie mate. Calling 0428 400 426 anytime will usually work. Regards kelpiebat

[Pug72]

I'll have a go at Lubing it and the linkages.

Here is a picture of the Bosch unit

If lubing doesn't work, I'll give you guys a ring and get a second hand unit

Thanks heaps

[julian b]

Ive always found taking wiper motors apart and cleaning everything including the grooves with a needle ,and spraying everything with wd40 seems to improve performance .I have been doing this since I had an ID 19 in the 60/s [6 volt]. If you want to contact Pugwreck they only answer the phone in the afternoon .

[Pug72]

I stripped the motor this afternoon, cleaned and regreased all moving parts.

And I found my electrical problem - there are two wires which have one end soldered onto a contact block and then run through a tiny hole into the actual motor. The sheathing on these wires has broken down allowing the wire to come in contact with the metal motor cover.

So tomorrow I will remove old wires and solder in new ones. I will also make the hole bigger in motor cover and fit a rubber gommet.

Hopefully this issue will be resolved..

[Beano]

All the same, it wouldn't hurt to ...sometime..... look at the linkages under your dash and push a bit of grease into them.