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She Just Won't Start

electrical

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#16 phillrulz

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Posted 19 April 2019 - 06:31 AM

 

Did you swap coil connections? Wrong polarity and spark is much weaker.

 

Thanks for the tip. I've swapped the ignition coil wires now.

 

And thank you guys for explaining the distributor points as well.  Makes sense.  

 

I've rolled it again, this time in top gear (not 1st gear!); the points open and close fully.  The coil is showing 12-13v on both connections with the points open, and it gives the same reading closed: about 12.9v on both sides.  Also, I'm only measuring 0.2-0.3 ohms resistance (not kOhm, just single-digit Ohms).  Bad ignition coil?

 

 

That coil is a bit low, did you take both leads off before measuring?

 

looks like you have an issue with the distributor. Can you measure resistance between that beat up flathead screw in the distributor and chassis and between battery negative with the keys removed from the ignition. 

 

You want there to be low resistance as the points closing shorts the coil to ground allowing current to flow. Also check resistance across the points when closed with the wire disconnected from the coil that comes from the distributor 



#17 ryanlogsdon

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Posted 19 April 2019 - 05:23 PM

 


 

That coil is a bit low, did you take both leads off before measuring?

 

looks like you have an issue with the distributor. Can you measure resistance between that beat up flathead screw in the distributor and chassis and between battery negative with the keys removed from the ignition. 

 

You want there to be low resistance as the points closing shorts the coil to ground allowing current to flow. Also check resistance across the points when closed with the wire disconnected from the coil that comes from the distributor 

 

 

Hi,

 

Yes, that 0.2 Ohm reading is with the leads off the coil.  Same reading when I put them back on.

 

Measuring from the beaten up flathead screw on the distributor to the chassis, I saw the resistance jumping around from 0.1 to 1.0, and showing 0.1 or 0.2 most of the time.

 

I wanted a better view of the distributor, and I removed the front grill.  When I touched a grounding wire, it disintegrated.  I'm heading out to see my Mom for Easter, but when I return Monday morning, I'll solder a new wire in.  Bad wire.

 

Happy Easter



#18 phillrulz

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Posted 21 April 2019 - 01:17 PM

 

 


 

That coil is a bit low, did you take both leads off before measuring?

 

looks like you have an issue with the distributor. Can you measure resistance between that beat up flathead screw in the distributor and chassis and between battery negative with the keys removed from the ignition. 

 

You want there to be low resistance as the points closing shorts the coil to ground allowing current to flow. Also check resistance across the points when closed with the wire disconnected from the coil that comes from the distributor 

 

 

Hi,

 

Yes, that 0.2 Ohm reading is with the leads off the coil.  Same reading when I put them back on.

 

Measuring from the beaten up flathead screw on the distributor to the chassis, I saw the resistance jumping around from 0.1 to 1.0, and showing 0.1 or 0.2 most of the time.

 

I wanted a better view of the distributor, and I removed the front grill.  When I touched a grounding wire, it disintegrated.  I'm heading out to see my Mom for Easter, but when I return Monday morning, I'll solder a new wire in.  Bad wire.

 

Happy Easter

 

 

That wire is most likely your issue. As to why its melted the acutallly copper, may be due to your very low resistence coil. Probably worth getting a new coil yours could have failed, or is the wrong one 


Edited by phillrulz, 21 April 2019 - 01:32 PM.


#19 ryanlogsdon

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Posted 24 April 2019 - 12:30 AM

Probably worth getting a new coil yours could have failed, or is the wrong one 

 

 

New coil's on the way from 7ent.com.

 

This morning, I soldered a new wire in place from "A" to "B" in this pic, and I tested that "A" and "B" were connected with my multimeter.  She still didn't start, so let's hope the new coil solves it this coming weekend.

 

Thanks again!



#20 ryanlogsdon

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Posted 27 April 2019 - 06:32 AM

The new coil and spark plugs went in tonight, but she's still not starting.

 

I can say this: the old coil needed to go.  When I took the multimeter to new one, I could see exactly what you guys meant a good coil behaves like.  The new coil holds right at 3.5 ohms resistance; and with the key in the ignition turned to the ON position, the new coil shows 12v on the positive side and about 0.1v on the negative side.  (The old coil showed 12v on both side.)

 

I pulled the spark plugs out after trying to start her up, and they sure didn't look wet.  How can I rule out (or test) if the fuel pump needs to go?

 

Thanks!


Edited by ryanlogsdon, 27 April 2019 - 06:32 AM.


#21 johnv

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Posted 27 April 2019 - 09:00 AM

Pull the fuel pipe off the top of the float chamber and get someone to turn the ignition on for a couple of seconds. Or turn the engine over if mechanical. You'll know if the pumps working!

Edited by johnv, 27 April 2019 - 09:01 AM.


#22 phillrulz

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Posted 27 April 2019 - 11:08 AM

The new coil and spark plugs went in tonight, but she's still not starting.

 

I can say this: the old coil needed to go.  When I took the multimeter to new one, I could see exactly what you guys meant a good coil behaves like.  The new coil holds right at 3.5 ohms resistance; and with the key in the ignition turned to the ON position, the new coil shows 12v on the positive side and about 0.1v on the negative side.  (The old coil showed 12v on both side.)

 

I pulled the spark plugs out after trying to start her up, and they sure didn't look wet.  How can I rule out (or test) if the fuel pump needs to go?

 

Thanks!

 

So you have a spark now?

 

Dont know how much you know about the mini fuel system, but the mechanical pump pumps fuel to the carb float chamber, in here a float operates a valve that closes the intake from the fuel pump, to prevent the engine getting flooded, this valve tend to fail open and piss fuel onto the exhaust via the overflow as i had, either due to a blocked needle valve, or a sunken float. 

 

To test the pump just take the fuel hose off the carb float bowl put it in a bottle and crank the car / ask someone to crank it.

 

If your getting fuel here, but not at the engine, id check the float will be three screws to take the top off, blow through the brass tube while actuating the float, with the float up the valve should close, with the float down the valve should open.

 

if this works, check the carb, take the carb bell off and check the piston is not stuck and can be lifted, careful not to damage the needle as you lower it back into the jet. 



#23 ryanlogsdon

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Posted 27 April 2019 - 08:21 PM

 


 

So you have a spark now?

 

 

Yep, I needed to get an inline spark tester, and each HT line is firing.

 

I'm letting the WD40 do its work right now.  I couldn't get the fuel line off for the life of me.  I'll report back on the fuel pump soon.

 

Thanks!

Ryan



#24 ryanlogsdon

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Posted 27 April 2019 - 10:01 PM

Pull the fuel pipe off the top of the float chamber and get someone to turn the ignition on for a couple of seconds. Or turn the engine over if mechanical. You'll know if the pumps working!

 

Bone dry!

 

Pic

 

Off to the store for a new pump....



#25 ryanlogsdon

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Posted 28 April 2019 - 04:01 AM

She's ALIVE!!!!!!!!  After changing the fuel pump, she's come back to life!!!  And if any of you are in the LA area in the future, let me know, because drinks are on me.  Thank you so much for helping me learn about and fix my car!

 

There's one issue with the new fuel pump...

 

When I turn the key to the on-position, the pump is loud, like you need to raise your voice a little to have a conversation.  I put in an Edelbrock Micro Fuel Pump 17303.

 

My dead fuel pump was electric, too, but silent.  Odd thing is that the old fuel pump was installed when the car was positive-ground (I switched it to negative-ground 2 or so weekends ago), and I thought electric pumps worked only with negative-ground.  Anyway, before I installed this one, I took my multimeter to the 2 wires to make sure I knew which side would be 12-volts and which side would be ground.  So I think I've got the wires connected right.

 

Thanks,

Ryan



#26 gazza82

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Posted 28 April 2019 - 08:24 AM

So the

The fuel pumps are easy to install and operate quietly, so you won't know they're there!

isn't entirely correct.

Have you mounted it direct to body or on rubber mounts?

#27 GraemeC

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Posted 28 April 2019 - 08:37 AM

My dead fuel pump was electric, too, but silent.  

 

Of course it was - it wasn't working  :ph34r:  :P  :D 

How noisy a pump is at first depends where its mounted, where the car is parked etc.  If its below the tank so it always has a head of fuel supplying it then it will be quieter, if it has to suck fuel through and prime itself it will be noisier.
It may be your last one had a non-return valve in it to stop it draining off the same.



#28 phillrulz

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Posted 28 April 2019 - 01:57 PM

ID also check that you have an inertia switch on the fuel pump, i spoke about mechanical as the age of your car doesn't come with electrical pumps. The switch turns off the pump if you roll it or get hit hard, prevents you getting cooked in your own car as the pump keeps pumping fuel into the engine / onto it. 



#29 ryanlogsdon

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Posted 28 April 2019 - 05:28 PM

 


Have you mounted it direct to body or on rubber mounts?

 

 

Direct to the body, but the old one had a metal strap tying it to the same place under the tank.

 

I looked into this model and found a reviewer say "Sounds like I have a hive of angry bees under my car!"

 

Does anyone have a fuel pump they like?  I think I'll replace this if it doesn't quiet down this week.


Edited by ryanlogsdon, 28 April 2019 - 05:29 PM.


#30 ryanlogsdon

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Posted 28 April 2019 - 10:57 PM

 


 

If your getting fuel here, but not at the engine, id check the float will be three screws to take the top off, blow through the brass tube while actuating the float, with the float up the valve should close, with the float down the valve should open.

 

 

Thanks for this tip.  When I started her up, the float bowl's overflow was pushing out a quick stream of gasoline.  I took the top off, cleaned all the years of brown sludge out, and it looks like that took care of that.







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