three questions about Mopar Elec Ignition

[Nacho-RT74]

first:
-the Haynes book says a good pick up coil testing reads 150 to 900 Ohms... whats the better, close to 900 or to 150... I guess less is better but wanting to be sure.

second:
-We have the pick up air gap must be .008"... what about if bigger or smaller gap ? whats better ?

third:
-Whats the substance used to seal the ECU boxes on back ? it does exist somewhere ? I opened one to repair one what it looks is an internal ground strap issue being loosen from ECU housing, thats the problem what makes an ECU replacement. A friend of mine already fixed his orange unit on that way. He discovered a loosen ground strap from housing to printed circuit box was the problem. He solded it back and worked perfect since that but had to use silicone to seal it back :S

[Sublime/Sixpack]

In response to your third question;  that substance on the back of the ECU seems a lot like a type of "Tung Oil" we used to seal electromagnets at a place I worked years ago.

[Nacho-RT74]

mmm, some clue if you can get it at some shop? ( if is that )

[b5blue]

On that note tung oil is very toxic....like PCB's! 

[Sublime/Sixpack]

mmm, some clue if you can get it at some shop? ( if is that )

You might want to inquire at a shop that rebuilds electric motors, etc. or electrical supply company. They may have something that you could use.

[Sublime/Sixpack]

On that note tung oil is very toxic....like PCB's! 

I wasn't aware of that b5blue. I wonder if people that use tung oil to treat wood are aware of that?

[Foreman72]

On that note tung oil is very toxic....like PCB's! 

I wasn't aware of that b5blue. I wonder if people that use tung oil to treat wood are aware of that?

its also used to make guitar necks more smooth...good to know its toxic

[Nacho-RT74]

mmmm by the description you are talking about, I think is not that kind of stuff

[Sublime/Sixpack]

The stuff I'm talking about (in my first post) is semi transparent and is a soft solid when cured.

[Nacho-RT74]

mmmm... ok... would have to check. This original stuff does have some kind of sand too

[tan top]

the  orange box on mine  , is like a semi hard black jelly ,  

[Nacho-RT74]

yes, same on everyone.

thread still keeps "unresponded" 

[nascarxx29]

Unrelated does anyone remember a older post where it was discovered that mopar ignition system double fired due wires switched at pick up.Might be in here.

http://board.moparts.org/ubbthreads/showflat.php?Cat=0&Number=1200956&Main=1162235

http://www.moparts.org/Tech/Archive/elec.html

[b5blue]

So pickup needs 375-425 ohm reading!

[Nacho-RT74]

mine is RIGHT NOW just right at 380... BUT LONG TIME AGO SAME PICKUP COIL WAS 100 OHMS BELOW

[Nacho-RT74]

Unrelated does anyone remember a older post where it was discovered that mopar ignition system double fired due wires switched at pick up.Might be in here.

http://board.moparts.org/ubbthreads/showflat.php?Cat=0&Number=1200956&Main=1162235

I discovered that about 7 years ago, not because wires were switched, like really pickup coil was damaged. I switched wires and noticed nothing changed, so that was my conclusion about the damaged pickup coil

[elacruze]

first:
-the Haynes book says a good pick up coil testing reads 150 to 900 Ohms... whats the better, close to 900 or to 150... I guess less is better but wanting to be sure.

second:
-We have the pick up air gap must be .008"... what about if bigger or smaller gap ? whats better ?

third:
-Whats the substance used to seal the ECU boxes on back ?

1. The pickup coil is a signal device, not a driver device so the output is not critical except that the signal is within a usable range.

2. Closer air gap is always better. Induction is reduced by the square of the distance. .025" is about max for inductive devices. .008" allows for operating tolerance without contact.

3. Don't know, but I've never had a problem re-closing circuit boards with good quality silicone. You could blow some Nitrogen on the board while resealing if you wanted to have some extra insurance against corrosion.

[TylerCharger69]

dont know about number one....number two.....    .008 is optimum adjustment...make sure that they pass "squarely" with each other and not more on the lower or upper edges.....number three.....just replace the box....they are cheap enough

[Nacho-RT74]

number two.....    .008 is optimum adjustment...make sure that they pass "squarely" with each other and not more on the lower or upper edges.....

yeap, I allways give a light mill job at pick up edges and also reluctor edges to guarantee the perfect gap from bottom to top, and also same gap at every reluctor point. They are never perfect with same lenght ( the location pin "outcenters" the reluctor a little bit too ).

number three.....just replace the box....they are cheap enough

NO MP boxes down here. I'd have to buy and ship to Venezuela... now is not same cheap huh ? ... sure aftermarket replacement stock units are available but talking about MP.

[TylerCharger69]

i bought a cheap 17 dollar Sorenson box (blue in color) never had a problem since!!  Got it either o'reilleys or autozone....cant remember which