dang blasted radio noise/interference... and more IP timing?

[jam sandwich]

I've been slowly pecking away at all the little quirks with my 89 7.3.. She's never run better thus far..
I had the timing modestly bumped up by Diesel JD and runs much smoother despite the same mpg maybe another bump would help? i could really use a pulse timer to see where my exact timing is at

But one problem thats been a constant issue is radio noise/interference. I threw in a spare aftermarket cd/fm stereo I had laying around and works great If I plug in an ipod through the auxiliary jack, but if I use the FM radio the interference is terrible, causing the stereo to go quiet and go to 'mono' mode.

I've replaced the FM antenna cable including mast. I was told that older fords have a 'noise suppressor' that usually bolts to the alternator, however mine does not have one..
What can I do to eliminate the fuzzy/poor radio reception?
I've also redone alot of the grounds throughout the engine bay, ensuring a good contact is made with the chassis, but nothing has helped thus far.

I did notice theres a yellow wired bullet plug on the passenger side that comes from the 'electronic modulator' that is left unplugged.. I wonder if that has anything to do with my lack of radio clarity?

I know its not a major problem, but honestly everything in this truck works dam well except the cruise control (the clutch switch is jumped) I even have decent AC and Heat!

 

[flareside_thun]

Have you grounded the alternator case to the chassis? Is the interference RPM based? is it clearer when the truck is off as opposed to on?

 

[jam sandwich]

I have not grounded the alt case to the chassis, I was thinking about doing that exact thing yesterday.. I'll give that a shot tomorrow.
There really is no difference in quality with it on or off. BUT when the truck is dead cold and I start the radio, it works as if everything is fine.. it only seems to be an issue once everything is warmed up.. or maybe im just imagining that?

 

[seawalkersee]

You have the spark plugs without the resistors in them and solid core spark plug cables don't you?

Seriously though, is your chassis grounded to the frame/engine/battery? I know you said you had the engine grounded, but what about the rest of the stuff.

SWS

 

[jam sandwich]

yes, Ive replaced the negative battery cables, grounded the frame to the engine, engine to battery etc. Not sure what other grounds to for..

 

[429idi]

What about the capacitor on the voltage regulator?

 

[jam sandwich]

Where is the voltage regulator is that also whats called the electronic regulator? how could I test/replace the capacitor?
i feel like most of my questions could be answered if I had a factory service manual for this truck..

 

[429idi]

Where is the voltage regulator is that also whats called the electronic regulator? how could I test/replace the capacitor?
i feel like most of my questions could be answered if I had a factory service manual for this truck..

It's the regulator on the passenger fender, it's a square box with a connector coming out of it. Some people ditch them when they install a new regulator, and I am told that will create radio static.

This may help some, it is not my video though.

http://www.youtube.com/watch?v=KjdaTypqj6o

 

[jam sandwich]

that video was extremely helpful and answered my question regarding the extra wire coming out of that voltage regulator.
Except, that alternator appears to have only 2 wires outputting while mine has 3 (2 small wires on that harness and the large one which goes to the starter solenoid)
Do auto stores sell replacement volt regulators for cheap?
If not where the heck can I find one of those suppressors to plug into my voltage regulator?

 

[flareside_thun]

http://shop.advanceautoparts.com/we...tor-BWD_5430534-P_204_R|GRP60003_567898662___

 

[jam sandwich]

Thanks for the link, picked up a replacement voltage regulator for 20$ at the parts store and made a ground cable from the body of the alt to the chassis, lets hope this solves my static issues

 

[flareside_thun]

Let us know man....

 

[jam sandwich]

Still the same dam crap. Maybe I just need to run an inline noise filter behind the head unit..

 

[riotwarrior]

I have static on my CD/radio that was not there on the stock radio...POS, now I want a new head unit.

Try another head unit, see if it does same thing...if so it's truck not the unit least you can rule out the unit that way.

Sounds like a bad solder joint in unit since you said works fine till warmed up.

 

[riotwarrior]

I have static on my CD/radio that was not there on the stock radio...POS, now I want a new head unit.

Try another head unit, see if it does same thing...if so it's truck not the unit least you can rule out the unit that way.

Sounds like a bad solder joint in unit since you said works fine till warmed up.