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Full Version: Mallory Install Part 3--No spark
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jaybird840
OK,
On to phase three of the Unilite install. I got the dizzy drive properly indexed and the dizzy set at TDC on #1. I verified by thumb-over-hole and by watching the valves. Now I am getting no spark out of the dizzy. Car ran on 009 dizzy two days ago. Replaced coil with new Bosch blue and installed the Unilite. I have checked and replaced all of the spade terminal ends, so I should have good contacts. From the Unilite, I have the brown wire to engine block ground, the green wire to coil neg (I assume that's the one with the minus sign), and red wire to coil positive (the one marked "15"). I say no spark, because I am getting no flash from a timing light (which worked two days ago, and shows to have power--it's digital). Attached is a pic of the coil. Let me know where to go from here....
Click to view attachment
jaybird840
Oh yeah, if your reply involves taking readings with a multimeter, please include detailed instructions. I recently purchased one, but have no idea how to use it... Thanks!
--jaybird
Jake Raby
I believe You have killed the unit-

Someone else has obviously hooked up your ignition to the wrong sides of the coil in the past, meaning that the coil really doesn't care what side of the coil says it is positive or negative (as they are labeled)

It appears to me that there is a hot, fused 12V INPUT going TO the coil negative side of your coil, where the green wire from the Mallory also leads. Where does that yellow wire go with the fused lead?

What is marked on the coil means nothing with points.

keyed 12V power must come into the coil at the same terminal as the red mallory wire is connected. This is coil (+) no matter what the coil says.

signal must go to the opposite pole with nothing else connecting to this pole except the tachometer lead.

It looks like you have 12V coming in on the pole of the coil that feeds the green wire of the Mallory.

If you do the unit is dead.
rhodyguy
same thing i thought when i saw the picture. it'll set you back the better part of a c-note to rectify the problem. btdt.

k
jaybird840
Jake,
Thanks for taking the time to reply... I purchased the unit NIB from a board member, not from the TIV store, and as such, your free advice is greatly appreciated. So, what's done is done at this point. Should the correct hookup be tach signal and green mallory wire on one side and red mallory and 12v to the other? I'm still trying to determine the origin of the yellow fused wire. Provided the unit is fried... a new one is available from Mallory for a Benjie, right? Thanks again for the free advice. (P.S.--when I hit the lottery, I'll be in line for one of your engines!!!)

--jaybird
jaybird840
OK, let me see if I can keep an expensive lesson from getting more expensive:

1)After a crash course in the multimeter, the unilite module is smoked. Used their testing procedure from their website, and there is no voltage drop when the module is blocked. It's reading a full 12 volts off the negative side with the optical window blocked. Should be 2v... So, I'll get a new module ordered post haste..

2) The yellow fused wire in the photo is the power supply for the fuel pump. No power coming through it. Unplug it with the key on, and the fuel pump goes silent. Is this a good place to have the fuel pump powered from?

3) The two black wires twisted together running to the same side of the coil as the yellow wire are the key-on hot wire for the coil. Good 12v with the key on...

4) How do I verify that the lone black wire on the back side of the coil is the tach wire? No voltage coming through it...

5) Last, and most importantly, am I correct in my assumption from Jake's post that it does not matter which side of the coil you use for positive or negative as long as all of the positive wires are grouped together on one side(key on 12v/fuel pump/mallory red), and the negative (tach wire and mallory green) are on the other? I really don't want to burn up another Benjamin on a Unilite module... I'd be better off taking up a cheap habit like Cocaine...

Thanks again for the input!!!!

--Jaybird
Jake Raby
QUOTE
1)After a crash course in the multimeter, the unilite module is smoked. Used their testing procedure from their website, and there is no voltage drop when the module is blocked. It's reading a full 12 volts off the negative side with the optical window blocked. Should be 2v... So, I'll get a new module ordered post haste..

Yes, exactly as i suspected. These units will not tolerate 12V being attached to the signal input at all, it would not suprise me if you have not fried the tachometer as well.

QUOTE
2) The yellow fused wire in the photo is the power supply for the fuel pump. No power coming through it. Unplug it with the key on, and the fuel pump goes silent. Is this a good place to have the fuel pump powered from?

I figured that. The fuel pump has a lot of load to be piggy backed off the ignition coil, I always run a relay to the fuel pump and feed it straight from the battery, you can use the 12V input from the coil that you have existing currently to "latch" the relay without issue. Relays remove load from the system and power the component with battery power directly. When I saw that fused yellow wire attached to the same lead as the green mallory wire I knew you made a huge boo boo.


QUOTE
3) The two black wires twisted together running to the same side of the coil as the yellow wire are the key-on hot wire for the coil. Good 12v with the key on...

Those are the ones that provided the power to kill the Uni-Lite module.

QUOTE
4) How do I verify that the lone black wire on the back side of the coil is the tach wire? No voltage coming through it...

Because it's black with a purple (violet) stripe on it-

QUOTE
5) Last, and most importantly, am I correct in my assumption from Jake's post that it does not matter which side of the coil you use for positive or negative as long as all of the positive wires are grouped together on one side(key on 12v/fuel pump/mallory red), and the negative (tach wire and mallory green) are on the other?

I have ran cars for years with the coil leads attached to the opposite poles of the coil without issue- some coils don't even have the terminals noted as + or -. If your coil hadn't been marked you would have been forced to think a bit harder and this issue would not have occured. As long as all the correct wires are connected to each terminal the engine will still function, but as soon as you connect a signal wire to 12V things will smoke.

This even happens with a point type system, I last made that mistake when I was about 10 years old.

QUOTE
I really don't want to burn up another Benjamin on a Unilite module... I'd be better off taking up a cheap habit like Cocaine...


If this unit was originally purchased through my store I will absorb the cost of the replacement module, just send it back to me with proof of purchase and we'll take care of it.

QUOTE
Thanks again for the input!!!!

No problem.
rhodyguy
just now saw the carb base. you need the jumper wire at the engine relay board for pump power. rob?

k
jaybird840
OK, thanks to the advice of Jake and Rhody, I'm up and running again. Called my FLAPS yesterday and they got me a new Unilite module overnight and they price matched amazon.com for $89. Got it installed, everything wired up PROPERLY (including wiring in the relay for the fuel pump--thanks Jake!!!). Hit the key, and she fired right off. Now I'm trying to make sure it's all good. Set the advance to 12 deg BTDC @ 700 rpm warmed up, and it idles really smooth--no more 009 flat spot.

However, on my afternoon test run, she now lacks a noticeable bit of top end. Max speed is now about 70mph. I can see the spark advancing using a timing light when I rev the engine (haven't done so over about 1750rpm yet). I installed the grey/grey springs (Here is a curious point... there were two sets in the kit that 'could' have been grey. One set looked "more" grey and was a smaller diameter spring with a lesser spring rate--these are the one's I used) and used the 16 degree plastic key in the kit to set the max advance to 16 degrees. Didn't mess any with bending the spring perches.

Any thoughts as to where my top end went?

Also, what plug gap is recommended for the Mallory using NGK plugs from aircooled.net? (running .040" now--old plugs were .030" with the 009)

From what everyone else with a Mallory says, it should run like a scalded pig. I'm sure we'll get to the bottom of it. As always, thanks tons!!!

--Jaybird
Jake Raby
Yopu CANNOT set the timing at idle speed!! The only time thats acceptable is IF the engine will operate only at idle!

Depending upon the internal settings of the distributor to properly dictate timing at "full advance" isn't wise.

Set the timing at 28* full advance, above 3,500 RPM and then see where it falls back to at idle speed and go from there. Full advance is all that matters to the life of the engine.

Glad you got it running, but you are not finished yet (but you would be if it would have came off my shelf :-)
jaybird840
QUOTE(Jake Raby @ Oct 10 2007, 04:57 PM) *

you are not finished yet (but you would be if it would have came off my shelf :-)


True that... That's why I plan on selling off my antique firearms collection next month to finance a Raby engine kit. 8^) (thanks again Jake!!)
Jake Raby
Will trade for firearms!!!!

Thats my other hobby!
jaybird840
QUOTE(Jake Raby @ Oct 10 2007, 05:50 PM) *

Will trade for firearms!!!!

Thats my other hobby!


Well.... we might have to do something about that. I'll shoot you a PM after I've assessed what I can live without in the gun safe. ar15.gif

Thanks tons for the free advice. pray.gif Both the timing and the mechanic were retarded (mechanic still is... av-943.gif ). Set it to 28 deg at 3500, and it runs like a champ now. My Dells even quit farting! Last, if you feel compelled to dish out even more free advice pray.gif pray.gif pray.gif , what kinda plug gap do you recommend? Stock 1.8 w/ 40 dells + bursch header/exhaust. I gapped them at 0.040".... Now that it's all lined out, I can go back and clean up the wiring install to make it tidy....

Jake Raby, you ROCK!! aktion035.gif

--Jaybird
Jake Raby
What plugs are you running?
jaybird840
QUOTE(Jake Raby @ Oct 10 2007, 06:50 PM) *

What plugs are you running?


NGK... (whichever one's aircooled.net sells)
Jake Raby
I use Bosch exclusively, but the same .030 setting should work fine.
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