98 FLD120 Wipers
 

My wipers take forever to start. I'm talking like 45 mins.. How can I check to see if it's the motor or the switch??? I use to be able to push the switch in and start them but that won't work now. Elementary I know but I'm an elementary mechanic . Any help will be appreciated.

Turn the wiper switch on and check for power and ground at the motor. If you have both it's a bad motor. If you don't have power or ground you have a bad switch or an open or short in your wiring or a bad relay.

Thanks.

Air or electric?

I just had to disassemble and clean and lube my Sprague HP135. Wipers were getting lazy.

Air. 2 lines coming out thru red button (trailer supply) bundle back of firewall.

So much for my first suggestion. Take a line off at a motor and see if it's getting a good amount of air with the switch in the On position. If it is then you've eliminated the switch.

Not sure why trailer supply would be hooked up to wipers.

Try what I did. Mine works alot smoother and easier.

I had to heat up the nut on the wiper arm to get it off.
Took motor all apart and cleaned every little hole with mineral spirits. Used O-ring lube for re-assembly. Manual says to use Dow Corning 200 (200wt). Vaseline would work in a pinch but will dry up in a year.

I checked my dash control knob too but it was fine.

I hope your air dryer is properly maintained because a contaminated air system will mess up more than your wipers. I hear trucks everyday where their air dryer is spitting every 20 seconds, meaning they have a major air leak and the compressor is cycling 100% of the time. That's messed up.