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Weak Spark no start (coil -->dizzy)


SpiderRat

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I recently bought my dime and drove it home (80+ miles) and the next day and until now it doesnt drive. 

 

Sparkplug test from sparkplug test (wire directly from coil & from plug wire #1 on to a grounded surface) results in a single spark during crank and one spark when key ignition is turned off. (2 weak sparks).  

 

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Ran super rich

The 32/36 webber that came with it was leaking on exhaust manifold (offy dual port).

Car drove and shut off during hard turns. had to push home. Cranks with no start

Tried to rebuild carb but flooded intake and plugs. Bought used 40DOCE upgrade thinking its just the carb.

After install the car still wouldnt start.

 

Known

1.Ez wiring kit

2.coils (used two types) generic and after marker Accel super coil. 12v during ON and 8v while cranking? no ballast on both (car didnt come with one but ran ok on the way home)

3.Used a Single point distributor and Electric dizzy for test. Same result

 

I feel that power (electrical) coil -->Dizzy is an issue. 

 
20150325_225146.jpg20150325_225115.jpg20150325_224856.jpg
 
 
 
 
***note I used two independent dizzy and coil combos and both had same results. PIc above is mix and match combo to replicate known issues...(no snapping arch when cranking)
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With no ballast resistor and a points distributor, it has likely burned the points or the coil if run for 80 miles.

 

The EI distributor needs no resistor if used with an EI coil. But if using a regular 12V coil then it still require the ballast resistor to keep the coil from overheating..

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I've never trusted EZ or painless on an import. Maybe wire the distributor as a stand alone circuit for troubleshooting. Is the tach wired correctly? Is the cap in good shape? I had the center conductor somehow disappear from my dizzy cap and it gave me fits for an hour or so figuring it out.

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Road warrior: I tried to upload photos but the site doesnt allow "extensions" for it to show. So i I just added Flikr links after the intial post. 

The car work previously without the balast on a single point dizzy. I check the coil and it said No resistor nessary printed on the coil.

I then used a El dizzy with a Accel coil

*Both setups resulted with the same issuie. No continous spark from Coil...however the ohm reading were 12v on and 8v cranking from the coil. I stuck a plug at the end of the coil wire to bypass the dizzy and the spark is the same "weak""not pulsing"Sparks on initial and and when done cranking"

 

Dolomite: Yeah I got to work with what i got and Ez looks painless. I wired the plug straight into the wire coming from the coil. I even put the end of the coil wire against a ground for a spark test. Same result. I feel somehow power is lost through the coil to dizzy from a connection issue since i believe 12v is present during the on position and cranks a 8v with no strong spark (faint and not present) 

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your a new owner and dont really know the system.

 

never just swap coil unless they are compatible.

 

if you have power on the blk /wht wire with key On

and power with blk blu wire on start you can get this running.But this is the stock wire colors.

 

since you swapped to many things at once we will be just guessing.

 

 

when car is trying to start the voltage will alwasy be lower as its dragging the battery down. This is why point distributors have a bypass wire(bypass the ballast). and give staraight battery voltage untill it starts then the power will go thru the ballast so not to burn up the points and cook a stock point coil.

 

 

If you have power to the coil it yill be able to figure this out. Maybe a combo of things wrong.

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Banzai510:Yes I am a new owner and not to familiar with electrical. I swapped out a working coil with a single point dizzy that came with the car when the spark situation was discovered with a known working dizzy and coil combo from another motor (l18). Both situations (weak spark) were replicated. (detail description above with picture links)

I know the power line from the EZ kit is red and using a volt meter from the coil with key ON shows (12v) and while cranking it drops to (8v)

 

Is the blk/wht wire - the power/battery line or Acc?

and Blk/Blu ignition/resistor line?

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blk wht is the key ON position!!!!!!!!! which will go to the fuse box of coarse via the key switch.

blk blu wire it the key in START this is the bypass wire. its shorted to the blk grn which connects to the other side ballast (its Y spliced under the tape)on standard 510s

 

But since this was running I will assume it was running right or wired correctly as it was running. maybe they had the prople before and put a differnt coil in there and then the proplems started and you bought the car. Using a EI coil will draw to much power and kill the points over time.

 

Point dizzys have condensor, bushing, and arching issues and you better knbow if that is a point coil in there as stock they are 1. 6 ohm and a 1.6 ohm ballast to prevent the coil and or points burn up.

 

 

whnr cking for spark most people just take the centor wire and place near chassis and then crank the motor. iif nice snapping arch about 1/8inch from chassis I would just call it good.

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thanks for the fast reply.

 The problem started before I removed or touched anything with the coil. I assumed my orignal 32/36 downdraft carb was flooding because the float might be to high. I noticed wet plugs and fuel in the intake ports when removing the intake manifold for further inspection.

Curently the car has 40 dcoe which is tuned and the owner brought his own coil and el dizzy from his working motor trying to get the car to run.

 

so it cranks cranks cranks and maybe one back fire. more cranks nothing. pull the plug wire to see if there is any spark?No only during ignial crank and when turning it off. Using the center plug from coil and placing near chassis to test arch...no snapping.

 

1.we used the setup that came with the car ( single point dizzy w/12v coil not needing resistor printed on it) Car worked before on this setup (l20b)-No snapping

2.we used the el dizzy and accel coil that came off a working motor (l18) with the 40 dcoe. Same result! -No snapping

 

we had thought that the dizzy has gone bad but it seems that it might be more of an electrical issue maybe because we used to setups independently and both had same results.

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so it cranks cranks cranks and maybe one back fire. more cranks nothing. pull the plug wire to see if there is any spark?No only during ignial crank and when turning it off. Using the center plug from coil and placing near chassis to test arch...no snapping.

 

if this is a point set up then the coil is grounded out most likely by the points or condensor inside(soemwhere)

If electric dizzy, I assume its bad or not wired up correctly

 

I also have to assume if the dizzy is at TDC when you reinstall but you should still get spark at the center coil wire when cranking. If clocked wrong cmoro will bot spark just the timming of the spark will be off.

 

on the carb the needle may be dirty and gets stuck thus not closing even if the float seems to level off at the correct spot.

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EI coils in my experience do not consistently spark off the center wire during testing. Testing the #1 wire always works with or without a spark.plug.

 

Anyways what I would do is:

1. Remove S wire from starter so it will not crank

2. Remove both wires from positive terminal of coil (including black/blue wire)

3. Have assistant turn key to Start

4. Measure volts at black/blue wire.

 

If it is zero, that is the problem.

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Zilla is correct I had weaker spark on the EI ignitions as I dont currently run them and never have.

On points and Pertronic I get good spark all the time cheacking from the center coil

 

B is +coil

C is -coil when using a matchbox if :there is another wire on there where does it go?(as in your above photo,the purple wire) tach?

as most onely have 1 wire on the - coil side

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ok ggzilla: I have moved to this setup (setup #2) -this is the coil and el dizzy that was on a working L18 that is currently NOW on my L20B --Accel Brand Coil

 

20150326_155447.jpg

 

1.Removed S wire (ez purple wire -label starter)

2.Removed both wires positive (ez pink wire - label coil & white line (non ez) leading to B side + coil)

3.Crank start

4.measure volts from Pink coil wire (i assume blk/blu is the the pink coil wire because its the only wire hooked up to "+" terminal coil.

 

***results: 12v reading when cranked and 0 when off.***

 

notes: Is right to assume that the wiring is correct? And I should move on to focus on coil/wires/dizzy?

 

We initally started the spark test coming off #1 plug wire. Once we noticed that the spark was faint (2 weak sparks during on and of key crank) we moved to center coil to try to isolate the problem. No luck so far.

 

 

Banzai510: Yes I should be more clear next time. The purple wire is a running tach line that hooked up to a floating line i found in the cabin in which I removed and regrounded to a good ground (pictured). However since the last post. I have reverted back to a "known" working combo (el dizzy--Accel coil pictured) for future tests. * I was mixing and matching coils and dizzys hoping to get some sort of spark and to further islolate the weak spark issue before. ie single point black dizzy and el dizzy combo.

 

stumped but still motivated to learn....

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Datzenmike: Yeah the local pick and pull has 81 datsun pickup. Is it safe to say the electric dizzy and coil  would be safe to swap (being a good condition). The el dizzy and accel coil are spoken for and are lent for test purposes only so I need to pick one up.

 

The ground screw connected to the bay is a good ground. (using a volt meter I place the positive tab on (+) battery and neg tab on the screw (ground)  which read 12v)- thanks for the heads up!

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Datzenmike: Sorry to make this so confusing. The last picture was only a reference pic of when I first got the car home. NOW currently I have the el dizzy and aftermarket coil on.

And yes I read that the point dizzy will need a ballast resistor but the coil has a printed text stating no ballest required.20150326_134812.jpg

 

AGAIN this is now not currently on the car but INSTEAD a aftermarket coil that is "known to work" with the EL dizzy currently on the block. 

 

Hope its less confusing now....

 

GGzilla: I ran a jumper across to (+) battery to pos terminal of aftermarket coil.

 

IMG_20150326_180119.jpg

 

results--The engine still doesnt start just cranks. Coil is HOT

**pic shows battery unplugged**

 

???

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