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beamsbox

Distributor Troubleshooting?

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Hello all,

I have an EA81 with a Hitachi disty I bought about two years ago that slowly died over about 6 months or so. It seems I replaced the Nippon-Denso one with the Hitachi, but failed to understand the necessity of replacing the coil to match the Hitachi. So, I assumed I had burnt the electronic control module inside the distributor. Eventually, I ended up with no spark, not even coming off the coil lead to the disty.

...so I replaced the little module... and assumed I'd be good to go.

But no love, I now have spark on the coil lead, but no spark at the plugs... The gaps on the star piece (which I removed) inside the disty seem even.

I am running on my old disty at the moment, starts right up, so I know the disty is the culprit... just not sure what/where.

Is there a way to determining what it might be in the disty? What are the processes of checking out a distributor? It seems like it should be working, everything is static, with the exception of the rotation, but still... seems pretty basic... any tips or tricks?

Thanks again!

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Correct dizzy cap? Is the little carbon tip present and making contact with the rotor button?

I’m not 100% sure that the dizzy caps are different between the two dizzy models, but it’s highly likely that they are. 

Cheers

Bennie 

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I have a 1984 Brat, it was running fine then my tac started to race up and down but not the engine itself. The distributor started to vibrate, then the engine began to cut out. I replaced the distributor and the engine started right up. I drove it around for the day without any problems. At the end of the day I started it up but it was difficult, and the engine started to cut out again. Where do I look to figure out what might be going wrong?

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Hmmmm... I thought the tach mechanically followed the engine speed...

I would start with the distributor you removed. Does it look good? Feel good? Have chipped teeth? Anything seem abnormal? Pics of it maybe?

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Well after further inspection I found the button inside the distributor cap had stuck. I flicked it a few times and the engine started right up. Needless to say I got a new cap and rotor. It seems to be running fine now. Thanks for the info. The distributor I pulled out was loose or wobbled. 

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On 1/8/2019 at 9:06 PM, el_freddo said:

Correct dizzy cap? Is the little carbon tip present and making contact with the rotor button?

I’m not 100% sure that the dizzy caps are different between the two dizzy models, but it’s highly likely that they are. 

Cheers

Bennie 

Ya, I have the right cap. They are different between EA81 and EA82, they are both keyed (notched) to fit.

Spent the day dickin with this guy. Still no go. I'm guessing perhaps the wrong module? The one I found on Rock Auto we're these: https://www.rockauto.com/en/partsearch/?partnum=LX515

I've tried multiple methods to check it out to no avail... Saw a video where you could check continuity of the module leads while rotating the disty, again no love.

I do have this handy electronic component tester. You plug stuff in it and it tells ya what you got. It reads the original module as multiple diodes. But it reads the new one as a transistor. Not sure if that helps someone smarter than I.

The only thing I have is spark from coil, no spark at plugs, still... 

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The spark from the coil, is this with the engine turning over or by triggering the coil manually?

I’m only ask because if you’ve got spark at the coil with the engine turning over, this indicates that the module is doing it’s thing. The issue lies between the coil, dizzy and four spark plugs. My guess would be a dud coil lead. 

If you’re triggering the coil manually you’ve got a working coil and the issue is most likely the module.  Do you have the little four star trigger wheel installed correctly?

Cheers 

Bennie

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Thx Bennie.

The spark from the coil is when I turn it over. After I replaced the module, I started getting spark, telling me it was working too. Not so sure about that now though, perhaps the module isn't working 'correctly?'

The reluctor (star) is in such that the pulse it generates while spinning (CCW) would ramp then drop out. Same as this:

s-l400.jpg

I know the problem lies in the distributor, as when I swap in the old one, it starts right up. Plus everything else is new...due to this problem... ;(

Edited by beamsbox

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If you have spark at the coil when cranking the problem has to be the coil wire, the cap or the rotor. As long as you installed the star piece correctly it has nothing to do with it except to trigger the coil. Start buy pulling the coil wire at the cap and see if you have spark there. If you don't replace and try again. If you do then it is the cap and/or rotor.

Edited by silverhelme

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You state have spark from the coil. I am assuming  that you  tested from the coil wire that goes from the coil to the distributer cap when cranking the engine, by looking for a spark at the end of the coil wire as it is place close to a ground.. I  am assuming you attached a spark plug to a wire,  grounded it and saw no spark, using the new distributer. I am also assuming you are using the same spark plug wires from the distributer that made the car run, proving the plug and wires are OK.

The only things left are the rotor, cap or that the wires are not pushed into the cap all the way making a good connection., 

I think you could use an digital OHM meter and check for continuity between the plug connector and the terminal inside the cap. If it shows open line the problem is at the cap/wire connection. Check all connections if you don't have most of the plugs firing the car wont run. I have never done this but I have checked continuity on plug wires this way. I if is an Open Line look at the connection point. Do you see a metal connectors where the plug/coil wires are pushed in?? Does it look like the wire connectors scraped the metal a little ??

See if there is continuity between the coil metal connector on top, and the button in the center of the cap.

Does it look like the rotor center connector has a wear spot from the cap? If so this would indicate there is a connection at that point. Is there a metal connector at the end of the rotor, maybe it broke or fell off? Again I have never done this, bit I think you could check for continuity between the center of the  rotor to the end of the rotor. 

If all this proves out I got to believe that the rotor or cap is not correct. Maybe you could try to measure the distance from the center of the rotor to the end. and the center button in the cap to the terminal on the inside. They should be close to the same measurement with the rotor being a little shorter. I don't know what the difference should be, but if it seams like a lot I don't think it will transfer the spark energy.

That deals with spark. Do you believe you got the firing order/ timing in the correct positions?

 

 

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Part numbers stamped in the outside of the dist body

How about quote these?

Are they the same numbers to begin with?

Edited by jono

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Thanks for the input everyone. I really appreciate it. Is there anyone in the Seattle area who might wanna take a peak at this? I could bring by all the necessary tools, etc. I'm kind of at a loss with this thing, other than buy a third set of cap/rotor.

5 hours ago, silverhelme said:

Start buy pulling the coil wire at the cap and see if you have spark there. If you don't replace and try again. If you do then it is the cap and/or rotor.

Did that, spark is good from coil wire. (Though it isn't super strong looking, not sure normal on these, but its not blue, that's for sure.)

I have two different caps and two different rotors, all are new. No combination of them will fire.

4 hours ago, pksjeep said:

You state have spark from the coil. I am assuming  that you  tested from the coil wire that goes from the coil to the distributer cap when cranking the engine, by looking for a spark at the end of the coil wire as it is place close to a ground.. I  am assuming you attached a spark plug to a wire,  grounded it and saw no spark, using the new distributer. I am also assuming you are using the same spark plug wires from the distributer that made the car run, proving the plug and wires are OK.

The only things left are the rotor, cap or that the wires are not pushed into the cap all the way making a good connection., 

I think you could use an digital OHM meter and check for continuity between the plug connector and the terminal inside the cap. If it shows open line the problem is at the cap/wire connection. Check all connections if you don't have most of the plugs firing the car wont run. I have never done this but I have checked continuity on plug wires this way. I if is an Open Line look at the connection point. Do you see a metal connectors where the plug/coil wires are pushed in?? Does it look like the wire connectors scraped the metal a little ??

See if there is continuity between the coil metal connector on top, and the button in the center of the cap.

Does it look like the rotor center connector has a wear spot from the cap? If so this would indicate there is a connection at that point. Is there a metal connector at the end of the rotor, maybe it broke or fell off? Again I have never done this, bit I think you could check for continuity between the center of the  rotor to the end of the rotor. 

If all this proves out I got to believe that the rotor or cap is not correct. Maybe you could try to measure the distance from the center of the rotor to the end. and the center button in the cap to the terminal on the inside. They should be close to the same measurement with the rotor being a little shorter. I don't know what the difference should be, but if it seams like a lot I don't think it will transfer the spark energy.

That deals with spark. Do you believe you got the firing order/ timing in the correct positions?

@pksjeep: those are all good assumptions, did all that. Check: plugs and wires are all good. Checked connectivity from top to carbon button inside cap.

Perhaps this is related (it)? When the cap is installed, I dont have direct connectivity from the top (coil input) of the cap to each of the four points. Should it literally touch each one along its path? Cause if so, I'd say this rotor is short for the cap (times two, apparently?) If I move the cap off center a bit, just slightly, and rotate the rotor until it touches one of the pins, I have connectivity from coil input across rotor to spark output. Thing is, it does that for both caps, both rotors. I haven't checked connectivity through the cap on the working distributor, so I'm not sure if they need to be actually touching (or just super duper close)...

3 hours ago, jono said:

Part numbers stamped in the outside of the dist body

How about quote these?

Are they the same numbers to begin with?

@jono: not sure what you mean here... but here's the side of the disty, tough to read...

image.png.8718e393e2466f2b82b2ad9f120ce1ad.png

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Picture not always worth a thousand words! Can't decipher photo. I guess I was getting at if you come up with legible part numbers first to compare yourself, others might identify something odd by numbers of both dist and your new cap n rotor

Idon't believe the rotor tip touches to contact, spark jumps small air gap.

What if you swap module from sparking dist to non sparking dist? Lever star off with two flat blades pivoting on dist body. Mind the tiny roll pin in hole of star that faces the flat of the shaft.

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Err.. that's right loyalty swap...forgot that detail

So to recap..the gist is you swapped in a Hitachi electronic.distributor in place of a ND electronic and can't get spark to plugs unless you change back to ND?

ND was not points was it?

Points coils usually get 8 or 9 V via ceramic resistor, with need ful 12 and exclude resistor. JIYDK

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7 hours ago, Steptoe said:

Points coils usually get 8 or 9 V via ceramic resistor, with need ful 12 and exclude resistor. JIYDK

Didn't know. I see the capacitor, I see no ceramic resistor. I believe the original ND is no points.

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