smoking spark plugs and not running smoothly

Hello,
So I have been slowly restoring parts of my 66 mustang. It was running before I started my last job where I replaced the spark plugs and rebuilt the carb.

I put it back together and it starts and runs and drives...but I noticed that it does not run smoothly...it really backs off on a regular basis. I have not really tried driving it more than 10 MPH for short period of time as I don't want to ruin anything but any ideas on what the problem might be?
I also noticed that one of the spark plugs emits smoke now and again...but I just attributed it to oil leaked around the area as there is a fair bit of it around.

I am wondering if the car would still run if a spark plug was installed incorrectly? Would this cause smoke? Maybe it is not tightened enough (it was a pain to get those in and I may not have tightened it completely...but as far as I could as far as I know).

How would I know if I installed the sparks improperly or rebuild the carb poorly? I had thought that if the sparks were not in correctly, then they would not fire and a cylinder would not fire and I thought that the engine would not run in this case.

I plan on taking it in to a shop a couple of miles away anyway, to have a professional check up on all my work anyways, but I'd like to drive it there rather than tow.
I just don't want to ruin anything by driving it when maybe I shouldn't be.
Any thoughts?
thanks,
Micah  

spark plugs will still spark.. if they are not fully installed...

and when not fully installed.. the tapered sealing area is not in contact with the head.. so gasses can flow around and past the threads...

when installing spark plugs.. use one of the spark plug flexible rubber installers.. an old spark plug boot thats straight...  a short section of vacuum hose on the end.. a 3 or 4 inch section of 3/8 vacuum hose or fuel hose...  if you can get a section that is straight.

get the plug against the threads.. turn it backwards till you feel it drop slightly then turn it in..

there are a bunch of other things that can go wrong and make it not run well...

but you have not described which motor.. which ignition system.. which carb you have..

there are a bunch of articles on carb rebuilding here..

just type the model number in to the search window above right......    1100.. 2100,  4100,   4150,  4160,  

go over everything you did.. no body will hold it against you if you got anything wrong..

there are a lot of smart people who know these cars inside and out...  

Hi wayne,
thanks for the help again...you were helping me out with the same car but under another name...the name on my other account will not let me access any forms for some reason.

I have the 66 mustang 289...2 barrel original carb.
Can't remember the model number though...think it was an autolight.

I was pretty sure I got the plugs in there tight enough but thought I'd check to see what the car would run like if one were not installed properly to make sure it was not doing any of those things.

The carb was rebuilt both to the packages rebuild instructions and to the mustang monthly how to section. So it should be back together just fine.
I also replaced the fuel filter and hose as you suggested I do.

The good news was that all of that worked and it runs...the bad is that it does not run smoothly. My friends who know the classic stangs very well could prob pick out the problem quickly; but they have been so busy all summer rebuilding other show cars for their job...so I've just kind of been sitting tight.

I'm hoping it just needs a tune up and am going to take it to a mechanic anyways for him to go over my amateur work...but thought I'd check on here one more time to see if there might be something I'm missing.

Again, it runs but it idles somewhat erratic on a consistent basis...then drives the same way...kind of a slow down in acceleration seemingly every few rotations of the tires.

The carb may just need adjustment....maybe I damaged a plug...thought I'd check the plugs first to see what would happen  to a running car if a plug was installed improperly.

Thanks again wayne!
M  

most spark plugs are CHEEP... 2 bucks... 3 bucks... a 66 mustang with stock ignition does NOT need more than that..

replace the spark plugs again...  check the gap first.. please.. do not use the center electrode as a lever to change the gap.. it snaps the ceramic insulator off up where you cannot see it..  causes misfiring..    you can also snap them or even crack them slightly.. when the socket slips.. some times you hear a snap noise..  just a crack.. thats enough to let the high voltage out ..

the spark plugs should thread in several turns... before you put the ratchet on to snug them down.

be sure to either look up inside the boot.. that the inner core can still be seen folded over inside the crimped area of the connector inside the boot... too many times.. the terminals inside the boot pull off.  if you have an digital volt meter that has a 200K Ohm scale.. you can OHM the spark plug wires...    the wires if good will display on the meter around half or less than the numbers on the display..

a 18 inch wire should read less than 18...  should display 7 to 13..

1,000 ohms per inch maximum.

you will want to measure the wires from the inside of the spark plug boot.. to the inside of the cap terminal.. or verify that you have each of the wires fully inserted..

do you have a dwell meter to check the running adjustment of the ignition points???  

unfortunately, that is all way over my head. I don't have any meters or tools to measure that. I have no problem bringing it into a proper mechanic who can deal with all of that.
I bought a set of supposedly very nice and correct plugs from Pep Boys...maybe about $40...so they should be adequate for my stock system (unless they gave me the wrong set).
It was meant to be the correct plugs for my system and thus I did not feel that I needed to measure and adjust any plugs...as I was not directed to.

Since the beginning, I have been planning on taking this car into a mechanic after I have done as much as I could...to look over my work and make sure it is safe for driving.

So, since I am not qualified to check all of the specifications of these plugs, I was just asking if there are major symptoms that I would immediately notice from  plugs that were not seated correctly or from plugs that were damaged or the wrong ones.

As the plugs seem to be such a major part of the system, I was guessing that there would be a very noticeable result from fouling plugs.
That is what I was looking for.

If not for this, then I would think that the problem would lie elsewhere.  

Did you install the washer's on the plugs? there should be a sealing washer on the plug, you install the plugs till they seat then tighted another 1/4 to half turn more. also check the gaps before installing as well  

54.. we are talking about a 66 mustang.. it will have RF9y spark plugs with 18mm thread and a tapered seat... but a good call..




so... can you find your receipt...    can you find a part number so i can make sure they did not sell you spark plugs that have TOO wide a gap that your point type ignition won't fire...

for some reason... parts guys have been pushing the most expensive spark plugs they can force you to buy..    40 bucks for a set sounds like 4.99 each for spark plugs..

Motorcraft Copper/Spark Plug
Part Number: SP-420
Alternate Part Number: 420

Autolite Copper/Spark Plug
Part Number: 45

Champion Copper/Spark Plug
Part Number: 409

these are acceptable spark plugs with points type ignition   i don't know what your local pep boys stocks...

what has been written...
spark plugs...


If the spark plug wires are not numbered as to their cylinder, place a piece of masking tape on each wire and number it.
Grasp each wire by its rubber boot on the end and remove it from the spark plug. If the wire sticks to the plug, a slight clockwise turn should help to loosen it. Do not attempt to remove the wires from the spark plugs by pulling on the wires themselves, as this will damage the wires.
Using a 13 /16 inch spark plug socket, loosen each plug by making several counterclockwise turns. If your car is equipped with a 351 Cleveland engine, Boss 302, Boss 429, or 429 SCJ, a 5 /8 inch spark plug socket should be substituted for the 13 /16 inch size.
Using compressed air (if available), blow the area around each spark plug clean. If no compressed air is available, wipe these areas clean with a rag. Make sure that no foreign matter enters the cylinders through the spark plug holes.
Remove the spark plugs from the engine.

To install:
Insert the plugs into their holes, and hand-tighten them, taking care not to cross-thread the plugs.
Using the spark plug socket on a torque wrench, torque the plugs to the proper specifications. (See the table in the general tune-up information.)
Install the spark plug wires, each on its respective plug. Make sure that the wires are firmly installed on the plugs. Check the firing order illustrations for the proper positioning of the wires.

INSPECTION & GAPPING


Check the plugs for deposits and wear. If they are not going to be replaced, clean the plugs thoroughly. Remember that any kind of deposit will decrease the efficiency of the plug. Plugs can be cleaned on a spark plug cleaning machine, which can sometimes be found in service stations, or you can do an acceptable job of cleaning with a stiff brush. If the plugs are cleaned, the electrodes must be filed flat. Use an ignition points file, not an emery board or the like, which will leave deposits. The electrodes must be filed perfectly flat with sharp edges; rounded edges reduce the spark plug voltage by as much as 50%.

Check spark plug gap before installation. The ground electrode (the L-shaped one connected to the body of the plug) must be parallel to the center electrode and the specified size wire gauge (please refer to the Tune-Up Specifications chart for details) must pass between the electrodes with a slight drag.

NEVER adjust the gap on a used platinum type spark plug.

Always check the gap on new plugs as they are not always set correctly at the factory. Do not use a flat feeler gauge when measuring the gap on a used plug, because the reading may be inaccurate. A round-wire type gapping tool is the best way to check the gap. The correct gauge should pass through the electrode gap with a slight drag. If you're in doubt, try one size smaller and one larger. The smaller gauge should go through easily, while the larger one shouldn't go through at all. Wire gapping tools usually have a bending tool attached. Use that to adjust the side electrode until the proper distance is obtained. Absolutely never attempt to bend the center electrode. Also, be careful not to bend the side electrode too far or too often as it may weaken and break off within the engine, requiring removal of the cylinder head to retrieve it.  

you may want to consider... unless you have some electronic ignition installed already... one of the pertronix ignition II or ignitor III drop in electronic ignition conversion systems..



there are several articles on them here in mustang monthly...


http://www.mustangmonthly.com/howto/173_0310_pertronix_ignitor_ignition/viewall.html

there is nothing wrong with running points and condenser... i still have points and condenser in my 70 ranchero... and its has 376,000 miles on it..   it had just turned 100K about a minute before the news came over the radio that the beattles had broken up... yep.. its been in the family a long time..  

now.. if you intend on working on cars...  you are going to need a few basic tools...

do you have a harbor freight tools near you ..  this is their automotive volt and dwell meter. has enough automotive range settings that this is probably all you will need...  item 95680 normally the same as you paid for the spark plugs. i see this week knock 10 bucks off that..




you will also need a timing light...  the one most people buy is the 30 buck version with the adjustment knob.. so you can adjust the flashing to  ZERO the light at TDC to make it easier to tell when you have the timing properly adjusted..



what is the adjustment.. so if your timing needs to be at 8 before TDC...  you can turn the knob on the back of the light to 8.. and the light will flash when the timing mark is at TDC.. so its easier to see the lines..

you can also look in and turn the knob to move the timing mark to TDC.. then look at the knob to know how far advanced the timing is..  

thanks for the awesome info!!!  

I got the #7 and #8 wires reversed once and it idled close to normal but when trying to drive, it would seem almost normal but then backfire loudly intermittently. A friend suggested checking the firing order and I just thought he was nuts, I just "knew" it was fine, haha, but they were crossed. Just saying.

Always support and keep the rachet straight with the plug, two hands, for just pulling or pushing may let the socket get to one side and crack the insulator on the plug.