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Discussion Starter #1
Hi Guys,

I drove my car yesterday. It accelerated poorly and had a very noticeable vibration on acceleration, coming all the way through the steering. It was totally fine last week.

The fuel mixture was richened recently as the weather has cooled but the car drove fine until yesterday. It was cold yesterday and the car just about warmed up to operating temperature even after 30 mins of driving at 40mph.

I took one spark plug out as I thought they were (part of) the problem. This is how is looks. In my eyes, carbon fouled and oily, but not too bad and can be cleaned. Plugs were last changed 18 months ago but not driven much.

Please could you help me 'read my plug' and figure out what the problem is.

Thanks!

Umanng

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You likely have weak ignition somewhere, if you still have points/ condenser or weak coil. How does the spark look? Rich mixtures and acceleration require strongest spark.
 

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Discussion Starter #3
I have the pertronix ignition points and coil so it shouldn't be that.

How do I see the spark? Do I plug the lead into the plug while its out of the engine?
 

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Pull the wire on the spark plug end and stick a screwdriver in it, hold the metal part of the screwdriver about a quarter inch from metal on the engine and have someone crank. Make sure you keep your hands away from the metal so you don't get zapped. Should have a big fat spark.

I think if you left the key on for a while with some of the pertronix they can be ruined. You could toss a set of points in and see if that works. Probably should have a spare set in the glovebox anyway in case of pertronix failure.
 

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Discussion Starter #5
They do look fouled up right? Not just regular ageing? I suspect it is mainly from insufficient driving and then when I do drive, it's stop and go city speed driving with way too much idling.

Should I try cleaning them?
 

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I see some deposits, most likely from fuel additives, and some oil residue at the base of the insulator, most likely from a seeping valve cover gasket. Other than that, there does not appear to be any soot from a rich fuel mixture and the insulator is a nice light brown indicating proper heat range. The electrodes aren't pitted either.

My suggestion would be to finish checking the ignition system. That would be pulling and cleaning the plugs, checking the resistance of the spark plug wires and their routing, checking the distributor cap and rotor, checking and adjusting, if necessary, the ignition timing and checking the vacuum advance operation. Assuming everything there checks out I'd pull a fuel sample looking for contamination, replace the fuel filter and go from there.

If you still have "issues" then I'd go back to checking primary and secondary coil resistance (you could do this initially if you want to cross this off the list right off the bat).
 

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do as mentioned above. sounds like choke or coil issue to me
Plugs are dry which is always better than wet
once you get the problem fixed the plugs should clean up on their own after a few long drives
 
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Discussion Starter #9 (Edited)
1. So I pulled 3 more plugs to see if the issue is consistent and these plugs had the same problem (carbon fouling?) but even worse than the first. More black soot, but less oily. You can see the soot rubbed off on my finger (photo below).

2. My choke is set to permanently open so it wouldn't be that. In fact today might be the coldest morning in the year. There was just a little play in the choke but I have reset it to 'hard open'. I have the Autolite 2100. My choke was gutted when I got my car. It has always lived in hot places - LA, SF, Honolulu, Sydney and Perth.

3. I will clean and reuse these plugs today and see how I go. Will report back.

4. I don't know how to do a 'tune-up' myself but if things don't improve with the cleaned plugs, I will have to go down to the mechanic. I've seen some videos and think I need to invest in a vacuum gauge and timing light.

Plugs.jpg
 

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Those plugs display classic burning rich symptoms. Since you didn't have the problem before, I would suspect the needle and seat are leaking or your floats are saturated and, well, not floating. :) Either situation would cause the bowl to overflow.

If you haven't rebuilt your carb in a while, I would suggest doing so. Even a good quality 2100 kit is inexpensive and rebuilding that carb easy peasy lemon squezy. And maybe fix the choke while you're at it.

Have fun!
 

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Discussion Starter #11
I've never rebuilt the carb (in the 7 years I've had my car) so that's a project to do!

I've had this problem before - plugs fouled and misfiring. Had the points swapped out for pertronix and the timing readjusted. That fixed it for the last 4 years or so, so I guess I had a good run!
 

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I've never rebuilt the carb (in the 7 years I've had my car) so that's a project to do!

I've had this problem before - plugs fouled and misfiring. Had the points swapped out for pertronix and the timing readjusted. That fixed it for the last 4 years or so, so I guess I had a good run!
Rebuilding a carb is doable if you have some mechanical skills. Buy a rebuild kit and watch a few YouTube videos. Take pictures during disassemble so you remember how things are getting together.
It’s a fun project


Sent from my iPhone using Tapatalk
 

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what coil are you running. most over the counter stock coils are .75 ohms including pertronox.
they are universal as they are so called

you need 1.5 ohm coil for a ford

you have to specify that as the parts guys dont know. they may have to special order it

Rock auto has them for about $15. Blue Streak Brand
 
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Discussion Starter #14
Yesterday I took out and cleaned all my plugs except #4. I just couldn't get my wrench in there with the stove pipe in the way. What's the trick!?

Anyway after being fully satisfied that my other 7 plugs were good, I went to crank the car and nothing. Not a sound! I checked every bloody electrical component in the car with my multimeter, battery, coil, solenoid, wiring, fuses wondering what the hell I had screwed up..... before fiddling with the shifter. Turns out it was just out of parking. What a horrible coincidence that this would happen for the first time after I messed about in the engine!

Car idled much nicer with the 7 cleaned plugs. Will go for a drive today, reset idle mixture and report back. Next definite project will be a carb rebuild.

Anyway, thanks to this I know my coil readings - 2ohms between positive and negative and 9.5ohms between output and positive. I think this falls in the correct range. I got this coil about 5 years ago with my pertronix.
 
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