LW 4000 Problems
- Thread starter 3xys
- Start date
whitescout
Banned
Usually, the overlength front means that something is blocking the front eyes when the machine starts. this could be due to overly large front bumpers that stick farther than usual.
If you believe that this is not the case, you could look at a couple of other issues.
The front eyes could be getting weak,and as a result, the eyes are not seeing each other. ( I would guess, that this would be what the tech said he was adjusting) ( turning the gain up on the amplifier)
Another thing that is possible, is that the machine is not stopping all of the way back at the tire stops. this could be due to several issues. Misadjustment of the front flag, front limit prox going bad, or incorrect tire pressure, or other mechanical binding.
If you believe that this is not the case, you could look at a couple of other issues.
The front eyes could be getting weak,and as a result, the eyes are not seeing each other. ( I would guess, that this would be what the tech said he was adjusting) ( turning the gain up on the amplifier)
Another thing that is possible, is that the machine is not stopping all of the way back at the tire stops. this could be due to several issues. Misadjustment of the front flag, front limit prox going bad, or incorrect tire pressure, or other mechanical binding.
lag
Member
Have you changes the sheer pin. Usually that is the first thing to check.
Next I would check the sensativity of the front eyes..An easy test is to turn on the output for the front eyes , open J3 then begin to slowly turn down the amp until the yellow ,and red lights go off. Good eyes should go below the "2 " setting. If the lights go off to soon ,you may have an eye going bad.
Do you have virtual treadle? if so make sure the back up eyes are working.
Next I would check the sensativity of the front eyes..An easy test is to turn on the output for the front eyes , open J3 then begin to slowly turn down the amp until the yellow ,and red lights go off. Good eyes should go below the "2 " setting. If the lights go off to soon ,you may have an eye going bad.
Do you have virtual treadle? if so make sure the back up eyes are working.
Thanks for the suggestions. We did change the sheer pin early on (I forgot to mention that) and continued to have problems. Hopefully adjusting the amp has taken care of the issues. It's a rainy day here so I'm sure we won't have many cars to test. Thanks again!
madscientist
Member
Absolutely.
Look in the J3 (stationary junction box on the bridge). The t-bar eyes pull to this box. In the right corner is either an amplifier relay (square module abt 4 x 4 x 1" with a dial on it) with 2 ice cube relays on each side or 2 amplifier relays. Reverse the amps if your bridge is newer and has 2 of them or the ice cube relays if not. Check the wiring / relay bases while there to see if problems are present. After switching the amps or relays and the problem changes from OL front to the bridge going to the end of the rails (not stopping at rear of car) you probably have a problem with the Y40 amp or relay. If the problem does not change then the front eyes probably need changed.
.......get between the short t-bar and wall, take your finger and slide it up over the photo eye. Now look across the finger lining up with the photo eye on the long t-bar. The arch should be at least an inch or so out of your sight line (also take your foot and push back on the arch while looking across).
Over time the high pressure kicking on can slightly bend the arch back and cause overlength front or front eye faults. If the arch is bent back enough to block the photo eyes, take the arch off and bend it back forward a little.
Over time the high pressure kicking on can slightly bend the arch back and cause overlength front or front eye faults. If the arch is bent back enough to block the photo eyes, take the arch off and bend it back forward a little.
whitescout
Banned
The last three posts have stated that they believe you are having an issue with the front eyes, and I agree, as I stated in my previous post.
The Issue with diagnosing your problem, is the same with all intermittent problems, is that the problem has to be duplicated to 100% correctly diagnose what is causing the problem. i am not the type of person that likes to throw parts at a problem, i would like to find the reason, and solve THAT problem.
With this said,
you have already replaced the shear bolt....make sure that it is tight, and that you do not have too much forward/aft movement of the spray bar, so it can block the front eye.
As J collins stated, take the j3 box off, and turn on output 40 , and then watch the amplifier while an assistant pushes the spray bar towards the exit, and see if the light goes out. If it does at any point, fix this situation by tightening the spray arm, bending it like j collins said, or whatever means you think you need to do.
If none of these tests help you out, I can suggest a crazy idea.... I see you are in Iowa, and that the problem seemed to go away for a while, and then came back......... Did you have some warm weather for a little while, and then it got cold, and then you had issues again????? If so, I would look at replacing 1 or both front tbar eyes, as you may have the tbar heaters adversely effecting the eyes. ( the heat is either shorting out, or causing excess resistance in the eye wiring)
The Issue with diagnosing your problem, is the same with all intermittent problems, is that the problem has to be duplicated to 100% correctly diagnose what is causing the problem. i am not the type of person that likes to throw parts at a problem, i would like to find the reason, and solve THAT problem.
With this said,
you have already replaced the shear bolt....make sure that it is tight, and that you do not have too much forward/aft movement of the spray bar, so it can block the front eye.
As J collins stated, take the j3 box off, and turn on output 40 , and then watch the amplifier while an assistant pushes the spray bar towards the exit, and see if the light goes out. If it does at any point, fix this situation by tightening the spray arm, bending it like j collins said, or whatever means you think you need to do.
If none of these tests help you out, I can suggest a crazy idea.... I see you are in Iowa, and that the problem seemed to go away for a while, and then came back......... Did you have some warm weather for a little while, and then it got cold, and then you had issues again????? If so, I would look at replacing 1 or both front tbar eyes, as you may have the tbar heaters adversely effecting the eyes. ( the heat is either shorting out, or causing excess resistance in the eye wiring)
whitescout
Banned
I believe that the easiest way to change eyes are to cut the "eye" part off of the old cable, and pull the new cable towards the box.
When pulling the eyes for the Tbars, I usually break the seal tight connections on the Tbar, and at the plate on the bridge. Then, you can pull the cable these shorter distances.
When pulling the eyes for the Tbars, I usually break the seal tight connections on the Tbar, and at the plate on the bridge. Then, you can pull the cable these shorter distances.
Waxman
Super Moderator
Are you sure it isn't a cable itself? I'd be sure of that first before you cut and splice.
Been there done that for prox switches and had it be the cable itself!
Just trying to help.
Been there done that for prox switches and had it be the cable itself!
Just trying to help.
whitescout
Banned
I am not saying to cut and splice, (I would never splice an eye cable)... I am saying to cut the old eye off of the cable, and use the old cable to pull the new cable in.
