Abs works most of the time now........goes for about 60-100 miles (many different trips) and then the abs inop decides to come on........but once I turn car off and back on it works for awhile again........any ideas? Going to get a scanner and try and figure this out

 

The clearance between the sinser tip and the reluctor wheel is off. This clearance is very sensitive and must be correct. I think the correct spec is ~.060" or so.

The metal particles you saw on the sensor magnetic tip did not come from rubbing the reluctor wheel. The particles cam from normal new ring and pinion break in wear. If the sensor actually rubbed the reluctor ring the sensor would be trashed.

 

I'd take a little more off of there, if that doesn't do it give us a call Monday. Bob

 

The sensor was hitting the reluctor ring because I could see the wear marks on it......I will mess with it some more today

 

There is a good chance that sensor is shot and those dudes are expensive. Maybe you will get lucky.

What material are you removing? If you remove sensor material (plastic area under the sensor) the sensor is moved closer to the RR. Sounds like you should be shimming the sensor away from the RR.

Is this 3 channel mod something you did or did you buy the Moser 9" w/ 3 channel mod? Is the ABS sensor depth position adjustable on your rear end or are you removing material from something?

Using a t-gage and caliper, start getting some measurements and determine what the clearance is between the sensor tip and RR. It has to be in spec or it will NOT work right.

 

The senor is approx $50.00. The center tip is what gets filed off to get the right spec's, it is the only thing that is adjustable. Bob

 

I bought it with the 3-channel option....I will post up how it goes later today

 

Sounds good, let me know. Bob

 

Grind the metal tip off of the sensor, are you serious?

The metal tip is an integral part of the sensors operation. The tip measures ~.030" -.035" or so and is designed for a specific purpose. Disturbing the tip MAY disturb the sensors magnetic functions and the ability to generate a stable AC voltage that the PCM requires for proper ABS operation.

Here is a much better way.
If you have to increase the clearance between the magnetic tip and the RR why not just shim the entire ABS sensor away from the housing using thin materials or an expendable feeler gage. This would require no tampering or alteration to the $50.00 sensor at all. The sensor can easily reposition plus there is an o-ring to ensure you don't get leaks when doing so.

I have a fabbed nine inch" rear w/ 3 channel and I can re-position my sensor the way I described above if the clearance between the sensor tip and RR has to be increased. I am sure the ABS sensor installs in the Moser in the same manner.

 

We've been doing it and it works, apparently there is enough material there to do so. Bob

 

Wow. I am going to seriously respectfully disagree here.
Sure seems like an overly complicated way to do it not to mention the possibility of ruining the sensor.

Not claiming anyone would do this, I am only trying to express my point with this next statement. But I liken your method of setting ABS sensor clearance to removing surface area from ring gear teeth to increase gear backlash rather than moving the carrier with a shim. Again no disrespect here Bob, but this makes no sense.

AFSTYZFR1
I strongly advise that you stop trimming the magnetic tip and shim the ABS sensor as a whole away from the housing.

I challenge anyone to prove that trimming the magnetic tip is more desirable than shimming the sensor as a whole away from the housing in order to achieve proper sensor magnetic tip to RR clearance.

 

The specific sensor that is supplied with the kit is actually for a 4ch rear. This picks it up on the side of the magnetic shaft. To use it with the single ring gear, it does need to have a point with the sensor. A 45deg angle on each side facing front and back of it, if you see the abs ring you will understand why, its a much finer notch pattern then a 4ch abs ring.

The sensors are being clearance'd from Moser somewhat, the only way to really distinguish the correct clearance would be to 100% assym the rear with the 3rd member that will be used. We set them up for .030 air gap.

The last vehicle i did with a 3ch worked correctly with .030 gap(moser spec). Abs worked correctly and quickly like it should.

 

how can i measure the gap? Stick something down the hole and mark it....then compare it to the sensor....? I didn't get a chance to mess with it today

 

Now this is starting to make some more sense.
So the sensor used in the Moser 9" w/ 3 channel ABS is actually the 4 channel sensor with the longer magnetic tip as opposed to the the normal 3 channel ABS with the the stubby ~.030" magnetic tip.

I was assuming that the Moser with the 3 channel conversion would actually use the 3 channel sensor like my 9" rearend does. I have read in another other post that Bob is reluctant to post pictures of the actual modification therefore I had to assume this.

That being said I still believe it should be possible the shim the sensor out as opposed to trimming the magnetic tip with a file or grinder. Maybe someone can post an actual photo and prove me wrong.

To mesuare the clearance I measure the distance from a RR tooth to the outside of the housing usinf a telescoping measuring guage and a caliper then measure the sensor tip from the sensor mounting base. Do the math then voila you have your clearance.

Can you post a picture of the mounted sensor and then the sensor itself?

 

Yes, Moser didn't exactly want the cat let out of the bag on how they are doing it just yet, which is why I as being a little evasive on it. Bob

 

Well you can clearly see the angle I was coming from now. I have the stock ABS sensor and stock reluctor ring on my 9" rear with no ABS issues.

Without posting some pics or more detailed information on the 3 channel mod there is little help to be gained from the board.

Hope you guys get it worked out.

 

Just got my exhaust re-done to clear the 9"....won't get to work on abs till the weekend.

I am going to leave the screw for the sensor off and slide sensor up and down with someone else looking at the abs light and see if I can get it to go out.

Don't know if it will help but I guess I can try it to see if I just need to remove more sensor material.

 

The way we were shown(first hand from moser), was to first install third member. Then put sensor in, rotate yoke to check if the ring is high or low. It has to be on high to set depth. You can clearly see the amount that will be touching, gap from mount surface on collar, to the black surface on sensor. This will be the zero gap, you have to measure what it takes from the high side the ring, to the surface of the collar. Use the butt end of a digital caliper. Take this measurement + .030 , then use that figure to find out how much needs removed from the sensor.

The sensor its self will generate a small amount of current when the ring is rotated, i check all of these out when installing them with a multimeter.

The sensor tip has to look like this to read properly, \_/ . It will take a more precise reading rather then a broad. The 4ch is read from part of the circle on the side so its a smaller surface vs the whole tip.

 

so why not just use a 3-channel sensor and make things that much easier?

 

Most things would lead you to believe this is the best, but the way the ring setup on here was done, is best done with the 4ch due to depth.

The stock 10bolt is a cast-in piece and can have a shorter sensor, but the 9" is spaced out so it needs a longer sensor.