I was messing around with the temp and fuel gauge the other night and found a small wound coil about the size of a sewing thimble attached to the cvr on the cluster. I seem to remember reading something about this on here but can't find it for the life of me. Can someone tell me what this is and do I need it. I took it off and tested the cvr and I am seeing the votage go up and down like it is supposed to. The gauges seem to be working better without it but I want to make sure I wont burn them out. Thanks.

 

I think it's a resistor of some kind. I also had one installed on my 65. I removed it about two months ago since the gauges all seemed to read about half what they should have read. Gauges work better and so far so good.

I'll be curious to see what others think.

Rich

 

Our gauges did the same thing. The temp gauge barely moved even after installing a new 180 thermostat. Removing the mystery coil seemed to make them work a lot better.

 

Got a pic? A resistor would only decrease voltage during these years and make them read lower afaik. So why would anyone install such a thing?

 

I will get a pic tonight and post it.

 

Here is what it looks like.

 

Huh, no idea. Two terminals, connected in series or, parallel?

 

There are actually 3 terminals. One on one end and two on the other.

 

Mine looked different than the one pictured above. Mine had a male spade on one end, female spade on the other end with windings in the middle. It pushed onto the IVR and the other end was connected to the wiring harness spade. I actually had two of the resistor gizmos, one that was intact and another that was damaged. They both looked the same originally.

I threw them away after I removed them so unfortunately don't have pictures.
Rich

 

Not sure if referring to similar/same CVR component mentioned in previous post?

Few years back posted a question, along with a picture of the 'doohickey' below and none of the member's who responded had a clue. Now curious if after all these year I have finally found out what the heck it is, and I do not know why I kept them all these years???

Purchased a couple spare instrument cluster years ago and the seller tossed these item in the box but I did not know where in the heck they went?? Recently reconditioned the instrument clusters on both 65's and tempted to install the 'doohickey' in series with the CVR unit but decided since I finally was able to get the gauges working best to leave well enough alone; besides, after going through a few spare CVR units, with mixed results, I found it less labor intensive to just purchasing a new CVR unit.

 

That is exactly what was on my IVR. I took them off and gauges worked fine. I had never seen them before. I assumed they were needed on the sweep style dash for some reason.
Rich

 

^ Radio Receiver Suppression Choke (Noise) Resistor - Located on backside of instrument cluster, attaches to ICVR

1961/64 F100/1100: B7LY-18A952-A

1965/66 F100/1100: C3MY-18A952-A

 

Aha! I thought it must be a choke but couldn't figure out what it was for. Now that I think about it, can hear a rhythmic popping every few seconds from the ICVR on AM frequencies as they make/break connection. Thanks ND.

 

Curious if my 'doohickey' serves the same purpose, considered testing but then again, if the gauges seem to function better w/out, and in my location I can not receive a.m. reception then what's the point??

 

AM band frequencies propagate better than about anything else, at least at night. Unless you live in a cave or bunker. They are subject to RFI though. Flourescent lights, LED, microwave ovens, dimmer switches, switched power supplies, baby monitors, defective power transformers, the list is endless.