crank sensor question

[1dollardog]

I was trying to replace the crank sensor on my 84 ttype. I bought a used one from a respected member of this board but when I got it it wouldn't exactly fit. It was clearly the same bolt pattern but the part with the fins or grooves is about 1/4" or so larger than the one I took off. The new one will not go back on due to this. The grooved section is hitting the balancer piece just enough that it won't allow it to slide over the center peg and be bolted in. Did they make different crank sensors? The one I bought is clearly different than the old one in this area but seems to be the same part (if that makes any sense). The grooved piece on the new one is clearly aluminum and the old one seems to be sort of a coated plastic in this area. If anyone has any experence with this I would greatly appreciate some help.
Thanks,
Steve

 

[turbofish38]

Is the plug the same? If it is than you need to replace the bracket too. Replacement sensors are different than the originals. Now for the bad news. The correct bracket is discontinued from GM. Check with GBodyParts.com Online as they carry the correct bracket to work with that sensor.

 

[1dollardog]

Is the plug the same? If it is than you need to replace the bracket too. Replacement sensors are different than the originals. Now for the bad news. The correct bracket is discontinued from GM. Check with GBodyParts.com Online as they carry the correct bracket to work with that sensor.

The plug and the bracket from the one I just bought are both just like the one I took off of my car. The only difference is the business end that actually picks up the signal from the timing on the balancer. That is the area that is a little thicker. The one I just bought is used and it came from a running hotair car. It seems that if my balancer was pulled out just a little that this would allow enough room for it to fit but theoretically it should just bolt on and plug in and work, but it doesn't.

 

[FlaBoy]

any way for you to post a pic of both of the parts side by side, maybe a closeup of the area of concern? A picture is worth 1000 words and all that

 

[1dollardog]

any way for you to post a pic of both of the parts side by side, maybe a closeup of the area of concern? A picture is worth 1000 words and all that

Yeah, I'll do that after work today.

 

[1dollardog]

figured it out

OK I think I have figured out why I thought I had two different crank sensors. The new one is taller than the old one because the old one was missing part of itself. The new one has what I kept calling fins or grooves that the old one didn't. The "grooves" are the guides that the balancer piece is guided through. The old one which I took off had had this piece removed or broken off. This may very well have lead to the piece not working in the first place. The remaining question(s) are why doesn't the piece fit and how can I make it fit. Fact is that it still is too tall to fit between the block and balancer. I think I can grind an 1/8th or so off of the guides without getting into the "sensor" part of it. Any imput would be appreciated.

 

[cool 84]

So, you're talking about the distance between the block and balancer and not the side to side movement of the sensor. It is adjustable by loosening the set screw.

What I'm trying to understand is are you saying the reluctor rings are closer to the block than they should be or the sensor is farther from the block than it should be?

For what it's worth, I've used both styles of sensor with no problems and I even run an 87 sensor now due to the cheapness with no mods other than an adaptor plug from caspers.

 

[1dollardog]

So, you're talking about the distance between the block and balancer and not the side to side movement of the sensor. It is adjustable by loosening the set screw.

What I'm trying to understand is are you saying the reluctor rings are closer to the block than they should be or the sensor is farther from the block than it should be?

For what it's worth, I've used both styles of sensor with no problems and I even run an 87 sensor now due to the cheapness with no mods other than an adaptor plug from caspers.

The sensor is further from the block than it should be (or the balancer is closer than it should be). I did get it on today though. I ground on the pilot hole that fits over the dowl guide jutting out of the block. Once I did that it fit over the dowl and bolted into place. Still not sure why it wouldn't fit in the first place though. After I bolted it up it had perfect clearence. I'm yet to get it started though, I'm still chacing down another problem.