The Stovebolt Site Forums The Shop Area General Truck Talk Problem with Trico windshield wiper

Dear fellow pickup enthousiasts,

This is my first post on this forum so i hope everything works.
Me and my father have an 1951 Chevrolet 3100 at home in the Netherlands. Because i live in the Netherlands I frequently have to deal with rain The original windschield wiper motor didn't work so yesterday I tried cleaning up the motor so it would work again. I installed everything back and the windschield wipers worked beter than before. The only problem is that the wipers only go up and then just stop. When i turn the the knob back the windschield wipers return back down. From what i saw on videos the windschield wipers should go automatically back and forth. Does somebody know what the problem could be?

Kind regards,
Thijs

Welcome - this is typical with these wipers most likely the motor needs to be rebuilt, this is the only place I know that will do it https://rebuildingtricowipers.com/ . there may be options to fix it yourself but I think parts are difficult if not impossible to get. I am sure others will chime in

Good Luck!

I recall that there's a switch that changed which side the vacuum goes into. It may be sticking. It should be removable from the outside without having to disassemble the whole thing. Maybe a little lubricant there would fix it. Worth a try before sending it off to a rebuilder.

I had that problem with one of mine. The switchover valve is small and can get stuck. I work on mine on the bench where In can see everything clearly. I use my central vac to power it.

I had the same issue with my original Trico wiper motor. It didn’t work at all, then I soaked it with ATF tranny fluid and it did work better but it would stop with just a little hand pressure. I sent mine to Fricken Wiper Service (aka the Wiperman), as Cletus1950 has suggested. And as he said, parts are nonexistent. Rumor has it, when Trico went out business, they sold all of their spare part inventory to only a couple of people, with one being the “Wiperman” and they do not sell any parts.

Shipping from the Netherlands may be costly. You could always email or call to see. Another alternative would be to install an electric wiper motor. Most of the cheap wiper motors (made in China), the choke cable is in the way requiring you to move it. The only one that installs without any modifications is one built in the USA by Newport Engineering. It sells for 250 US dollars which is about $75 more that the Chinese imports but from the reviews on this forum, that is what I recommend.

Good Luck with whatever choice you make!

klhansen hit the nail on the head. There is an exploded view of a Trico motor at Schematron.org and about 3/4 of the way down the page it shows the controls which they label "rocker" but we call "reverser". This MUST snap over center when one works the shaft by hand. As stated, it under a plate so dismantling the motor is not necessary.

Thank you for your reactions they really help!

When i took te motor apart I made sure to place everything back how they should be. When I had the front cover off I saw that when I turned the shaft the spring hanger jumped back and forth normally, so I don't really know why it doesn't work with the vacuum on.
As Phak1 mentioned, shipping from the Netherlands to America is really costly and it's not really worth it. The truck itself is in really good condition (for a patina truck) and runs and drives great. We only drive it for fun and for advertising purposes for our gardencenter. So buying an electric motor is also a bit pricy for the little bit that we drive. I always make sure to check the weather before I drive it. But as I said the weather in the Netherlands is really unpredictable. So it would be nice to have working wipers again.

Is Rain-x available in the Netherlands? It is much better than nothing.

Possibly there's something in the motor itself that prevents the vane from going far enough to make the valve switch positions. If the wiper on the vane is displaced to one side, that might be it. I'd try a little bit of lube on the switch. You can't make it worse.

Have you confirmed you have full vacuum at the motor? Is the vacuum hose/line kinked or blocked somewhere?

Mike B

The discussion of a vaccum motor versus electrical motor is something the owner has to decide for themselves.
Below is some information about the vacuum motor that may help you to make a decision.

The Trico model number will be printed on the small cover. Trico SSM-412-2 was used 1947 (second half year) to 1953 (See attached photo 01).

A good comment from Denny concerning vacuum requirements (page 1):
https://www.stovebolt.com/ubbthreads/ubbthreads.php/topics/647167/1.html
Consider that as the 216 or 235 I6 engine wears from use (basically piston rings), it produces less available vacuum for the wiper motor operation.
The long term optimum solution may be to use a vacumm motor rebuild service as discussed.

Here is a link to a discussion and pictures of the parts under the small cover (it may be similar to yours):
https://forums.aaca.org/topic/302219-trico-vacuum-wiper-motor-parts/

Even with original new cars and trucks, the vacuum wiper system was "lacking" when the engine is under load.
There were two original options for providing more or consistant vacuum.
The costly Trico ElectroVac (attached photo 02) and the AC (GM) dual action (fuel and vacuum) pump (attached photo 03).

A caution about lubrication of the vacuum wiper motor. Consider that the lubrication used can also be sucked back into the intake manifold and into the engine.

Additional information:
Although not original, you can purchase updated (1947-53) wiper arms that uses the 1954 style clip-on 10" wiper blade.
This style of wiper blade is a GM improvement.

Again thank you for the help!

I still haven't solved the problem. The engine is completely rebuild so the vacuum is very good and strong (also tested) so that isn't the problem. Removed the front cover and checked the switch mechanism. Can't find anything that's off so it is a mystery for me.

I had my Trico rebuilt a few years ago. Since I very rarely drive it in the rain, I don't put it through much work. Have noticed that if I turn it on with very little if any pressure on the pedal, it works pretty good. If I gun it, the blades come to a quick halt. As soon as I back off on the pedal "wipe, wipe, wipe" the blades go. And when I turn the switch off, it jumps to its park position. I have an extra motor and should get it rebuilt, someday.

Today i also mada some time to check mine. Just bought it and they didnt work. At least i thought. In my 1940 buick it was just one turn button to open the vacuum and they worked. In the chevy i have a button that screws and a pull button. Checked the inside and all look good. When i now run the engibe and pull on switch it goes quickly to the left and stays there. When i push the switch back it goes back to its starting position. I also live in the Netherlands so will encounter the potential rain. I will take out the motor again.

Ok. Found the reason. The passenger side it took apart looked good. Didnt check good enough and found out the damage part as seen on the picture. So took the part out the passenger side motor and placed it in the driver side motor. That one is working now. The passenger side i will disconnect first. Only problem now is that it will hit the center post and goes over the window frame on the outside

Very nice to hear from a fellow dutchman who loves these beautiful trucks Robby!!
I have the same problem with the wipers only going down when i turn the switch off.
The damaged part from your motor makes the vacuum switch. I know for a fact that parts for these motors aren't available on any dutch website. I would suggest to take the good one apart (or glue this one back together), trace the part on a piece of wood with the same thickness and cut/drill it out. I think it is easy to remake that part when you are a bit handy.
How far does your wiper go over your center post? Mine also goes a little bit over the rubber (that holds the center piece in) when its almost completely down. I don't find it a very big problem as long it wipes the glass.

About a cm over the centre post and 2cm over the top of the window frame going the other way. For now i will just make 1 wiper workable for the RDW check.

If it goes over the window frame, try to take the wiper arm off and reposition it to the correct place when the wiper is fully down (or up in your case). On our truck the left wiper arm was mispositioned so when it went down the wiper went under the window frame.

The broken part (yoke) is either phenolic, bakelite or fiberboard (pressed wood fibers in a resin).
I would also consider fiberglass-epoxy laminate.
The attached pictures may be helpful for creating a replacement part.

The arm(s) on the motor, wiper linkage and the tower arm determine the distance of the cleaning (wiping).
Wear of these parts can make the distance longer and shorter.
The position of the wiper arm on the grooved drive determines beginning and ending points.