M151a1 Windshield Wiper Motor ?

[aceecaus]

So, I am trying to figure out why my "new" wiper motors aren't wiping. I assumed it was the vacuum pressure, or lack of it coming from the vacuum pump. I started there and I assumed the pump was bad, so I hooked up a vacuum gauge and it read 15" of pressure. I read in the TM that 10" at idle is "normal", so I should have plenty of vacuum seeing I am 5" above the "normal" reading.

Moving up the line to the wipers, I kept measuring. I read 15" at the "u" tube from the dash, 15" at the wiper switch, and 14" at the T junction where the line T's to the two wiper motors.

Where am I going with this?? It turns out that even with one line hooked up to a "new" wiper motor, it still doesn't turn (well, just barely and NO way will it turn 2 of them). I took off the plate with the diaphram gasket on the wiper motor, and it was clean but dry. Isn't there suppose to be oil in there? Is there a way to adjust it? Additionally, the gasket grew when I removed it and there is no way I can re-use it.

Suggestions? Is there a re-build kit or should I just get 2 "new" ones again. When I use the term new, that's how they were described to me when I bought them. They did come in the box sealed and with the build date tag in the box. I may have just gotten a couple of bunk ones.

Thanks in advance.
Ace.

[rickf]

It sounds like maybe you are putting the vacuum line on the wrong port. Or there ma\y be a restriction in one of the vacuum lines which will allow you to read 15" on a gauge but flows not enough volume to run the wipers. I would take one of the motors and hook it directly to the line from the vacuum pump in the engine compartment. If it does not work there I would guess you have bad motors. Again, make sure you are on the right port. Those "U" tubes that run under the dash will clog with rust a lot because they are the lowest point in the line and condensation ends up there. That might be your restriction.

Rick

[FREDERIC]

Hello, Aceecaus.

This is not the oil is the fat quantity you need.

[aceecaus]

It sounds like maybe you are putting the vacuum line on the wrong port. Or there ma\y be a restriction in one of the vacuum lines which will allow you to read 15" on a gauge but flows not enough volume to run the wipers. I would take one of the motors and hook it directly to the line from the vacuum pump in the engine compartment. If it does not work there I would guess you have bad motors. Again, make sure you are on the right port. Those "U" tubes that run under the dash will clog with rust a lot because they are the lowest point in the line and condensation ends up there. That might be your restriction.

Rick

Thanks Rick, but I'm reading 14" at the T right before it hooks up to the motor. I'm thinking its the motor, as I hook one line directly to it and it still chugs and goes in one direction but doesn't have enough umph to return the other direction.

I got two new motors coming so I'll see if that's the problem.

Thanks,
Ace.

[FREDERIC]

Hello,
Your leak is the wiper motor, it is not even nine tight because you have the meter in fat.
Driver's side motor is reversed.
Aceecaus, may be I do not understand you

[aceecaus]

Thanks Frederic. My motors are correct, I think they are bad. The passenger side is better than the driver's side. I'll change them out and go from there.

Ace.

[bazookajoe]

one thing I have found is that u can have dirt plug up metal tubing pieces on the mutt.....did u try just blowing thru the tubing to each of the motors to check for obstructions and free flow? Low tech first place to try.

[aceecaus]

Did that and it was clear, but thanks!

Ace.

[muttguru]

........ I took off the plate with the diaphram gasket on the wiper motor, and it was clean but dry. Isn't there suppose to be oil in there? Is there a way to adjust it? Additionally, the gasket grew when I removed it and there is no way I can re-use it.

Ace,
the problem is most likely the dry diaphragm. I think that is what Frederic means when he talks about using "fat"....he means grease.

This subject has come up before on the M38 Tech Board and here is a typical answer. I don't like WD-40 but for certain problems it does have its benefits. Try soaking/softening the seals using this, then use a thin (THIN) coat of rubber grease as a lube for the softened seals.

http://www.g503.com/forums/viewtopic.ph ... er#p915559

Ken

[tankerm60]

did you check the weld, where the T branches off ? Possible crack and loosing pressure ? Check with a soap solution
TankerM60

[FREDERIC]

Yes it grease, again thank you Ken.
I forgot to rubber there is a renovator molecular, silicone.
You have in your mutt is the brake fluid, it is pure.
The process that makes rubber deteriorates is complex (rupture of intermolecular bonds).
The officials are numerous:
In a somewhat random order, I would cite:
Sun (UV)
Oxygen and particularly, ozone
Hydrocarbons in general.
The polytrol could indeed have a curative action on the material surface, but only, silicones have a preventive action (and curative)
For cracked tire I have treated with silicone, which feeds the tire dry.

I do not buy new tires.
Guaranteed effect.

[baios]

frederic what made are the tires?????

[FREDERIC]

frederic what made are the tires?????

That Michelin manufactures tires for the French army, it is not in commerce, it is intended to 4x4 vehicle Peugeot 700 / 16.
With luck in a military surplus.
Here is the P4.