PDQ LW 4000 rail question.

[Indiana Wash]

I own two PDQ LW4000's. Recently, the drivers side tire that engages the rail and moves the bridge toward the rear of the car has begun to spin. I replaced the rollers and the tires and it still spins unless the pressure is 45 lbs. The only difference I could find between this rail and the rest is that all of the other rails have a black coating still on them. Is this a traction enhancer? They are SS. If it does enhance traction, what is it? Thank you for your help.

 

[getnbusy]

I have not seen SS rails with black stuff on em. Possibly just dirty ?? Idk.

Try taking both bridge tires off the machine. With the tires off the rim, measure the circumference. I would think they need to be pretty close to the same. I would also be sure to use matching tires. I have had the best luck with the OEM tires

 

[Scrub Free]

I'm guessing that the dirt has been worn off that rail due to tire spinning. Be sure the bolts are not broken off the clamp that holds the long axle together.
If it is actually slipping then a collapsed or worn rail is likely check for soft spots and measure compared to the others. If it's worn you can weld a thin piece of as along the rail. One of my rails were fixed that way a long time ago I dont know if it was for a traction issue.

 

[soonermajic]

Interesting about the tires. I actually have 2 different tires on mine. Maybe that's why it doesn't always load properly (home position)...?

 

[Bud]

Could be a few things. Tire pressure is the first choice. I run about 30lb. Too little can give trouble along with too much. They are supposed to be at 25. Both tires should be the same size as per PDQ. 4.50/etc etc??? Is the tire badly worn? They should be the "knobby" type tire and not the straight tread. Next would be is there a lubricant on the rail? This can happen sometimes when not watching when spraying the festoon rollers or something blowing out of a truck bed. Clean the rails and tires. I use a good solvent, mineral spirits, etc. If the tire is slippery it would be best to replace it. I suppose there could be a gear box problem but it shouldn't just be one side or the other. The only other thing I can think of to do would be to rough up the surface of the rail with a grinder. It doesn't take a whole lot.

 

[DiamondWash]

If it's worth a shot you could buy 2" traction anti-skid tape from home depot and stick it to the rail make sure you just clean the rails really good for the adhesive backing to stick to them, I also have had that issue with tires slipping years ago on a laser and we also roughed up the track with a grinder.

 

[koliver]

Early on, the rails had an epoxy paint applied to the bottom of the rails with "grit" sprinkled in it to give traction. Later on, diamond plate was added to the bottom of the rails. You can purchase the diamond plate and add it, but it would require someone coming to the site with a welder. Additionally, you need to look at the tires that you are using. The outside diameter of the tires, based off brands, will vary. This will cause the tire to spin as well.