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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: lostagain on September 10, 2010, 11:11:32 AM

Title: MC5C Windshield wiper
Post by: lostagain on September 10, 2010, 11:11:32 AM
The driver's side (of course) wiper will not go at times. Or it will start and stop on the outside of the windshield. When it works, the valve at the dash makes a hissing noise. I took the valve apart and cleaned it with solvent per the instructions in the MCI manual, put it back together with white grease. I worked the valve back and forth, but it feels like it is too stiff. I think that this might be the problem. I could not see a way to take it out of the body to clean and lube some more. Suggestions? Or should I just call MCI for a new one.

JC
Title: Re: MC5C Windshield wiper
Post by: zubzub on September 10, 2010, 11:40:05 AM
I don't know about MCI but I fixed my WW valve ( we are talking control valve?) by replacing it with an off the shelf truck part.  there are a few different configurations for park etc...so you need to understand how you valve works.  Just throwing it out there, may be easier/less$ than
mci parts.
Title: Re: MC5C Windshield wiper
Post by: bevans6 on September 10, 2010, 12:12:08 PM
My passenger side does that.  I don't think it's the valve, i think it's the air motor.  They sure use a lot of air!  I have no fix, just share the problem...

Brian
Title: Re: MC5C Windshield wiper
Post by: lostagain on September 10, 2010, 12:27:29 PM
Brian, I didn't think it is the motor because the hissing noise comes from the valve on the dash. The pass. side, which works well, doesn't make that noise. I will check out the motor on Monday just to be sure. We are off to Calgary shortly to a motorcross race.

JC
Title: Re: MC5C Windshield wiper
Post by: bevans6 on September 10, 2010, 01:35:51 PM
Sorry, I meant on mine when it stalls I think it is the motor.  may be similar symptom, but different problem.  I just stop and my wife gets out in the rain and pushes it to get it going again, since it's on her side...

Brian
Title: Re: MC5C Windshield wiper
Post by: robertglines1 on September 10, 2010, 01:43:12 PM
try shooting a little air tool oil in the air supply side--just might lube up rubber seals etc and get it going..might be years of build up and the air tool oil will cut it and lube it...we have a expert here on electric conversion....he has worked hard and is enjoying the benefits...
Title: Re: MC5C Windshield wiper
Post by: gumpy on September 10, 2010, 06:18:46 PM
The hissing is probably the exhaust from the motor. There's supposed to be a tube on it that goes through the driver defroster motor compartment (center of dash) and through the floor to the tire compartment below. Without that, you will hear the motor exhausting air on every stroke. With the air line in place, you don't hear it because it's in the spare tire compartment.

It could also be the plastic piece on the motor that is notorious for cracking. I fixed mine with epoxy or JB Weld.

The stopping is probably the motor needing to be rebuilt or at least cleaned and lubricated. Try shooting some super light oil into the air inlet line into the air motor. Some swear by Marvel Mystery Oil in there. Sometimes that works. Sometimes it doesn't.

Probably not the switch. The switch is supposed to be a bit sticky so that it stays where you put it. That's how you regulate the speed of the wipers. Turn the switch a little bit and the wipers go slow. Turn it more and they speed up. etc.

Title: Re: MC5C Windshield wiper
Post by: lostagain on September 13, 2010, 04:53:01 PM
It's working good now. Took me a day and a half, but I think I got it.

I took the air motor out. Not that easy because some of the screws holding the front panels on were seized. One I had to drill out and would still not come out with an easy-out, so I thought some heat would be good... Propane torch... Soon I had a fire inside the front under the dash. I could smell burning rubber, and I could see it through a 1/8th hole. Scrambling to get in through an adjacent panel, and strong language... finally get there to put out the fire on the DOT air lines to the other side wiper motor! I guess they were really close to the metal panel I was heating up. So I had to fix that too...

Anyway took the motor apart to find the inside all gunked up with black, dried up old grease. So I cleaned everything up with solvent, re-lubed and reassembled. Went into town for the 2 big O-rings, (2" X 1/4", on either side of the rack), but could not find any, so put the old ones back in, they did not look too bad. The plastic valve body that mounts to the side of the motor is old looking with cracks. The exhaust port broke where you screw the fitting for the hose. I fixed it with epoxy putty. Put everything back together and it is working fine now, hopefully for a long time.

JC

P.S.: I looked up the price of a new air wiper motor from MCI: $600 and some...