Club 80-90 Forums

the crackle stops when you remove the antenna because the radio isnt picking it up. its radio frequency interferance you are getting, which is why i say its ignition related on FM.
AM broadcast recievers will pick up any electrical contacts opening of closing.

to check it the antenna is earthed, disconnect the neg wire from the radio earth point and if the antenna id connected, the radio should stay switched on.

Tried that - disconected the black wire and the radio went dead! It did come back when the side of the radio touched the metal dash - which I suppose is earthed itself.

So MIGHT it still be the aerial earth based on that experiment Moki?

What next? HOW do I earth the aerial.

Oh, and purchased and fitted a supressor - to no avail.

what exactly did you put the suppressor on, because you described ignition spark interferance, not alternator noise.

what antenna is it? a stock VW one on the a post?
if so it is connected to body earth via the phillips screw that holds the antenna to the body.
if its a drill through mount it will have a serrated earth washer that bites into the body from underneath.....

the only true way to stop interferance is at source, ie the engine bay.

I put the suppressor on the back of the radio - supposedly it would, said the man at Halfords, stop interference from all main electrical sources... It is an 'in-line' suppressor. I think I might go and ask for my money back... not sure on what grounds though...

Not sure what sort of antenna... it goes through the bodywork and is attatched by screwing a hollow onto the post on the outside, there is no washer or philips screw, but there is scuffed metal on the inside section which fits against the inside of the bodywork when nut is tightened.

However, I tied some metal wire to that and attatched that to earth... radio still wouldn't work without earth conection or panel conection through side of radio... neither did the noise go away...

So, as you I'm sure rightly point out, it is back to the engine bay... but why all of a sudden?

So first things first, the crackling is very fast now when accelerating - so guessing from what you say it is the 'king' lead - is that the lead from the 'round' thing to the top of the distributor, i.e. the one that feeds the four spark leeds? How do I test it.. and them? Simply get new ones?

Thanks - really, thanks for your help, this is driving me mad... I'm one more curse away from an auto electrician!!

Sorry, missed out a word.. a hollow 'nut'

sounds to me like you need a new antenna anyway....

leads break down with age, but it maybe the dissy cap..... dont think you want a auto electrician really tho, its a trial and error thing.....

you need to find out for sure if the antenna is connected to the body electrically first, either a bulb and apiece of wire, or multimeter job, then start looking at what is causing the noise....... looking in the engine bay when the engine is running in the dark may let you see with the naked eye where sparks are jumping!

when did it last have new plug leads and dissy /rotor?


one thing at a time tho......

Right, aerial first - removed aerial and tested with multimeter - no matter where I atttatch wires there is no earth 'travel' from the aerial to the radio end at all - corroded aerial inners I think. So, a new aerial first...

Next, HT leads and king lead (which I suppose is the single lead going to the distributor?). Where is best to buy them? Can you still get them new? I pulled them off and examined, they are very 'stubby' inside and very green! On their way out?

I'm ordering new aerial as we speak.

Just to check Mocki, this is the right one for the 'hole' in the bodywork type? It looks the same...

http://www.justkampers.com/shop/type_25 ... hella.html" onclick="window.open(this.href);return false;

Not sure when the HT leads and Distributor cap were last changed - think i'll order new HT leads, plugs and Distributor cap with the aerial. I have a 1982 s litre Aircooled: are these the right bits:

Distributor cap: http://www.justkampers.com/shop/type_25 ... cap-1.html" onclick="window.open(this.href);return false;

HT Leads: http://www.justkampers.com/shop/type_25 ... d-set.html" onclick="window.open(this.href);return false;

Are these all simple to fit? I suppose with the leads you just pull the old ones off / out and put the new ones in in the right order... doing one at a time so as not to forget! As for the distributor cap, you unclip one with the side clips and shove the other one on? Simple as that?

I await your response Mocki before ordering.

And let me just say a big thanks for your help... I hope it won't disappear until the problem is solved as I'm relying on you now ha ha.

sorry, been a tad busy.......

yes they look like the right bits.....
if i can help, i will..... but im relying on your descriptions and replys to be my eyes and ears!!

Thanks - yes it is a slightly busy time of year... but I have an understanding wife... the kitchen table is once more covered in bits... aerial bits this time, which is better than engine bits I suppose. I will repost information as soon as the new aerial and leads arrive and iv'e fitted them.

Until then have a good Christmas Mocki!! And everyone else!

Oh... earthing? Just realised something that may or may not be important. My radio works on a positive from the leisure battery - but don't know where the earth comes from for radio and aerial... does it matter which battery the earth comes from? Both batteries are earth-strapped to the battery boxes, so guess they are the 'same' earth, is that right? Plus this fault has JUST developed, so I suppose if it had been incorrectly wired it would ALWAYS have produced a crackle?

as long as both batterys are earthed to chassis, all is well.....

if you connect a bulb between the pos of the leisure battery and the outer of the radio antenna plug that goes to the back of your wireless does the bulb light when the antenna is fitted onto the van?

Didn't use a bulb, but a voltage meter - and the answer is no. So, took aerial out and attatched an earth wire from the van to the grip of the aerial where it would conect with the chassis - but still no voltage present, so... cut a thin line into the coaxial just below aerial... and attatched a definate earth there, this time it did register: so clearly the metal of the body of the aerial is not conected to the outer coaxial cable, thus I have ordered a new one.

As a point of interest, my mobile transistor radio makes the same noises when on in the car with the engine running.

Going to try same experiment using the hole where the aerial goes tomorrow to ensure that thas section of the body is earthed. Well, maybe not tomorrow!