CB noise

[Kenny Simmons]

I have a 2006 Pete with engine computer noise. I have applied for help from Cat. They sent a trouble shooting chart that brings me back to engine componets leaking. Anyone had this problem? Noise is controled by fuel being applied to engine and sounds like normal back round static that just increases in volume.

[wc5b]

Can you tell us whats up with the CB end of the issue? How is the CB Powered? Is it into the Cig Lighter or straight to the battery? If it is to the battery, have you tried to "choke it"? Are the antennas grounded? Most drivers don't bother to do these things and alternator whine is very common because of it. Normally sounds louder and more rapid with your acceleration.

[n4mgr]

What you are hearing is likely alternator noise. It sounds like a whine that increases with throttle and decreases as you let off. This can also have other causes.

My first question, Is the truck yours?

Second, Are you just wanting to get rid of the noise or do you want the radio to work better as a system?

Third, Are you willing to put some money into the problem?

Well start with my reasons for these questions. Number 1, The solution to this problem requires some modifications to the truck. The alternator will need some capacitors put on to eliminate this and no truck stop or cb shop will know what you are talking about if you asked about this. You may get a ham who has a technical background in mobile HF to do this, I don't know. Number 2, If you want the system to work better, you need to be sure you have a good ground, installing ground straps between the antenna mounts(Both sides if co phased) and frame. Also, Make sure you are using the best antenna you can afford. Stay away from Francis, they are worthless, even if you once talk to the guy down the road on them. K40's are good, The so-called Monkey Made antennas are good, just be sure the ground is good and the swr is as close to 1:1 to 1 on Channel 19. Also, you should find a way to attach a strap from the back of the radio(one of the screws should be ok) and run it to a point in your cab that has continuity with ground. You will need a multi-tester for all of this and that can be picked up from Wal Mart or Lowes/Home Depot. As for number 3, We have covered most of that, you will need a 50' roll of ground strap, a multi tester, about 20 to 40 6guage lugs(these are hard to find but worth it), Ferrite's(try googling DX Engineering)(these need to be placed on the wires to your ECM and on the wires to your injectors).

Now back to grounding. You need to ground you exhaust stacks, just take the strap with a lug crimped good on each end and place on a exhaust clamp on each side and run to the frame. You will need to drill a hole in the frame and bolt the lugs there. Find a few of the unused bolt holes in the engine and get some bolts to fit them(any CAT dealer or service facility should have these). Place at least one strap on each side and run to a bolt in the frame(the shortest length possible is recommended and you can drill with no problems or just use a bolt already there. Take the ferrites and place them on each of the wires that go to the injectors(may take 2 per) and on the wires to the ECM(may take from 6 to 8 ferrites). This will get rid of most if not all of your noise and will also help the AM/FM radio as well. If you have any questions let me know, I will try to help if I can.

[Kenny Simmons]

The truck belongs to me. The noise is not from the alernator. I have had every radio tech I have found on the road that I heard was good to check all my grounds to be good. I have had a connex 4300, 4600, 4300-300, and now a Ranger. Multible Galaxy's. Wilson 2000 truckers on the mirror mounts with new coax as of last weekend. Again all grounds including a new ground strap on the ecm to the frame. Noise is there. If you uncouple the antenna coax there is not noise at all. Remember, when the truck is sitting still the radio is perfect, quite and receives exstremely well even when you rev up the engine.The static comes up with the boost gauge and back with the boost gauge once you get to 20 mph. So far to date I have spent well over $1000 on just rewiring grounds and testing everything anyone can think of. My next move up until tonight was going to Jackson, MS and put it on the dyno there and check my fuel curve as well as check ecm componets while we can see the noise when the engine loads up.

[n4mgr]

Ok, try the ferrites I mentioned. Do to the high pressure fuel delivery used in todays heavy diesel engines, the voltage to the injectors is fairly high. The wiring and all emits what is known as rf and this is nothing more than interference, static and all. Buy the ferrites(about $100 worth if I'm not mistaken) from DX Engineering(website) or maybe Universal Radio(Columbus, OH). Just place the ferrites over/around the wires and place a cable tie over them. You should immediately notice a difference.

[wc5b]

mgr is right. This STILL sounds exactly like alternator whine. There is more to it then just the grounds. I would try to choke it with the ferrite's first. This can be a big headache in Most big trucks. There are MANY things that could cause it, but I am willing to bet that its something that can be hunted down on the radio side, not the Cat side.

[Kenny Simmons]

I will do the ferrites ASAP! This is what I felt was happening but I could not explain it or now how to fix it. Why my truck? Everyone else I talked said they had no problem. Maybe they are not as perticular as I am. Problem is I have had some good systems before and know what it should do or not do. Thank you for responding!! I will let you know how it turns out. I still am planning to get the dyno test since I turned Lucy up last November at Cat in Jackson, MS. Bobby and I want to see what the fuel curve is now.

[TruckerLlew]

Since you mentioned that the noise increases with your boost guage activation, you may want to put a few Ferrites on the wiring leading from the gauge, if you can get to it. You may have something emitting RF from that gauge. Check the sensor it is attached to as well.

[Kenny Simmons]

I have ordered a total of 20, 10 large and 10 smaller gauge from DX Engineering. I over nighted them and the total is $140, but $40 of that was freight. I can't wait to test them. Also, I will be doing some more grounding such as my stacks which are not yet.

[n4mgr]

Originally Posted by Kenny Simmons

I have ordered a total of 20, 10 large and 10 smaller gauge from DX Engineering. I over nighted them and the total is $140, but $40 of that was freight. I can't wait to test them. Also, I will be doing some more grounding such as my stacks which are not yet.

This is good Kenny. I sure hope it resolves the problem. Noise is a major problem for radios in semis, regardless of manufacturer. I suggest the steps I recommended to you to anyone who wants a better signal and less noise. Remember, you can talk to them unless you can hear them. Let us know how it goes.