Just bought 67 250S - Will not start...

[gisenberg]

I just bought a 1967 250S from a widow. The husband had just bought it and it ran at the time. I know that he changed the fuel pump and it appears that he changed the plugs and wires. When I turn the key the engine just cranks. I checked that the fuel pump was working and gas is flowing. I also have sprayed starter fluid into the carbs and nothing happens. I found what I think may be the old plug wires in the trunk. I took some of the plugs off and put them back on just to make sure they are on ok. Every now and then the engine actually want to turn over, but thats about it. How can I check to make sure that their is spark for the engine to turn over?

Thanks for any help with this.

You can buy a spark checker from a mcparts store for about $10.00. If you don't have spark, I would make sure you have 12v going to the positive side of the coil, then I would check the point gap(about .016 inch/matchbook cover) and replace the condensor. I would first make absolutly SURE that the plug wires are correctly installed. If someone left the key on with engine off the coil/points/condenser(sic) could be fried. A 12v multi-meter can diagnose the problem. Also availible for cheap at mcparts store. Good luck. It's probably a simple problem.

[gisenberg]

Thanks for the reply. I will go get the meter. I am sort of a newbie at this. Is the Coil the item that has a plug wire from the distributor to the Coil?

The engine now spits once or twice during a 5 second crank when I spray starting fluid in. There was a puff of smoke that would come from the Carb. when it spits. In fact there was a flame once. Is that been I am getting a spark?

Thanks

[300SDog]

Or you can work the poorman's spark test holding an ignition wire (with rubber handled pliers) unscrewed from the plug resistor cap about 1/4" from the cyl head while somebody else cranks the engine. Spark between the wire and cyl head oughta be BLUE...... if it's orange then you've got ignition spark problems, could be internal corrosion of condernser or coil.

Lesser known fact: crummy condenser ($5 part) can prevent the venerable old 6cyl Haeckflosse/Benz from starting.

[Mark DiSilvestro]

Yes, that thing the center distributor wire connects to IS the coil. Most likely the 6 plug wires are mixed up. By now, it's possible repeated starting attempts have flooded it too, so you may need to remove and dry the plugs. While you're at it, you can connect a plug to each plug wire and check for spark - no need for a special tester. The firing order should be cast into the valve cover. You'll need to locate #1 plug position on the distributor. If no one's messed with the distributor position, there should be a little line or notch at the #1 plug position, visible on the distributor rim when you remove the cap. If the distributor position hasn't been changed, #1 cylinder is at top dead center on the compression stroke and the balancer timing mark is at top dead center, the distributor rotor should point to that notch.

Happy Motoring, Mark

The coil is a round top device that has one sparkplug
wire attached to it(going to the center of the distributer cap), along with a small wire going to the points in the distributer. The other small wire gets positive 12 volts when you turn the key on. If the car ran before and doesn't run now, try to trace backwards where peoples fingers were last.

It sounds like you may have spark. It may be too weak to fire the plugs due to a faulty points/condenser and/or a bad coil. Kepp in mind also, however, that the spark needs to happen at the right time in order for the engine to start. It sounds like the spark plug wires may not be connected in the right order if there was a set in the trunk. That would cause the spitting back through the carb., and a no start condition. The correct firing order is stamped on the valve cover. I was thinking, and you don't really need a meter to test the ignition system. Just a $3.00 12 volt test light.

Please be very careful using starting fluid. I blew a engine up once using starting fluid. Starting fluid car ruin your engine with little provocation. When I say "blew up" I mean it suffered internal damage. Instead of starting fluid try using a tablespoon or two of gasoline. If the air filter is off the car, you may have a flame shoot out of the carb if things aren't adjusted right. Keep the air cleaner on when trying to start unless you have a fire extinquisher handy. Let us know what questions you have and we will be glad to help.

[gisenberg]

Thanks alot guess for the great info and warnings. I have a feeling the plug wires are wrong for starters. I did take all of the plugs out and made sure the gap was correct. The plugs looked to be pretty new. There are 2 little clamps that hold the distributor cap on and I found that one of these clamps was not on and the cap was loose. If someone took the dist. cap off I am assuming from your information that the order may not be what is stamped. Is that correct? I will attempt some of your ideas tomorrow as it is pretty cold out and dark now. I have the car partly in the driveway as I had to pull it home and my driveway is sloped and the car to heavy for me and my friend to push by ourselves. We were trying to get is close to the garage but the chain that my friend was pulling me with slipped off when turning into the driveway, flew and punctured a pretty good hole in the corner of my radiator. So, now I have even another thing to fix.

When you say the order of the plugs are stamped is that under the long cap that the plugs are in? Please excuse my ignorance of terms, I am new to messing with cars, although I am finding it interesting and fun.

Thanks

[gisenberg]

Thanks alot guys....I can't spell!

[djd]

Hello,
I too have a '67 250S. Wonder how many are left??
The most common causes of no start on an old car are: 1.Ignition 2.Fuel and 3. Compression. Usually in that order.

1st gotta have a good battery - especially in cold weather...
Everybody's got their own technique, but if it were me, I'd pull a plug wire and one of the plugs and lay the plug on the engine. The wire should fit tight and the plug's threads MUST be making good contact with clean metal on the engine. Have someone crank the engine and look for a strong spark at the plug. (Should be blue and may make a little "snap" noise.) If you've got spark you can usually rule out points, condenser, coil, rotor, cap, plugs and wires.

You should also hear a "chuff" of air from the open spark plug hole. The noise and the spark should happen at about the same time. (No noise = no compression?? Possible but not likely.) If the spark and the noise are way out of sync, look for the distributor cap on wrong, plug wires out of sequence or timing way off.

If the spark is good and it happens at the right time, I'd look for a fuel issue. Put the plug back in and try pouring in a tablespoon or two of gas. (Careful!)
If it tries to start, could be old gas in the tank, chokes not closing, problems in the carbs, fuel pump...

Let me know if you need pictures of anything. Except for the alternator (Chevy) I think mine's pretty original.
Dennis

[gisenberg]

Thanks Dennis,

Do I only check one plug for the blue spark or all of them. Also if only one does it matter which one? Also is the number 1 plug the first one closest to the front of the car? When you say put a tablespoon of gas, where do I put the gas, in one of the Carbs.?

I think the year and model are 67 and 250S, from the documentation. There are manuals from a couple different models. The plate on the back says 280S, but I really don't think it is. How can I tell to make sure that I am correct on the year model?

Thanks again!

The plug wire closest to the front of the motor is number 1. If you have spark at number 1 then chances are you have spark at the the other plugs. The key here is that the plug wires HAVE to be connected in the correct firing order. If they are not, the motor will not start and will backfire.
this may help:

1. Remove distributer cap, leaving wires attached. Make sure both clamps are clear of moving parts.

2. Have someone rotate motor with the key inside the car while you watch the plastic rotor in the center of dist. rotate. You are looking to see if the direction is clockwise or counter-clockwise.

3. There should be a small line or mark on the distributer where the cap makes contact arount the body of the dist. This is your number one cylinder reference mark.

4. Rotate engine with starter in quick short turns of the key until the rotor is in line with the reference mark.

5. Now, replace cap on distributer and note which plug wire the rotor is pointing to.

6. Going in the direction of roation of the rotor. start with number one plug wire and insert plug wires into cap using the correct firing order.

The firing order is a series of six numbers stamped into the valve cover. under the word Zundfolge(German for firing order). Reading from left to right is the correct firing order you should follow on the dist cap going in the driection of rotation starting with number one cylinder.

Cylinder number one is at the front of engine. Number 6 is closest to the firewall. The rest go from number 2 to number five in sequetial order on motor.

You should pour a tablespoon of gas down each carb throat, and then at least replace the metal cover that goes over the top of both carbs before you attempt to start.

Please be carefull. I had a leaking carb catch on fire when the car backfired and there was no airfilter to contain the flame. Have a fire extinquisher handy.

Let us know if you have any questions and good luck.

[gisenberg]

I found the firing order. I do not see any marks for the #1 plug in the distributor cap or on the dist. itself. I unplug all of the plugs and just tested one. I got fire on 2 of the 6 dist. connections. So, I used the first one for #1 plug and proceeded hooking the rest up in the correct order. I put a tablespoon of gas in each carb. The engine just cranked nothing else. I moved all of the plugs over to the next one that had fire for #1 and when I cranked I got a shot gun backfire. Is that positive or no?

Thanks

Yes, that sounds like you are getting close. The good news is that the engine and ignition system are probably ok.
The backfire is a sure sign the plug wires are not in the correct order. Call me crazy, but it is possible that someone, before you came along, did this on purpose in order to be able to take advantage of the situation and buy the car for cheap.

If your distributer does not have a mark for number one cylinder then you will have to bring number one cylinder to what's called "top dead center on the compression stroke". What this means is that you want to use the marks on the big pulley that runs all of the belts in you car to bring the motor to the correct position. Then you can install the plug wires in the correct order.

The pulley will have a series of numbers and marks on it. You can see the marks if you look down under the water punp and slightly to the right. You will see a small pin pointing towards the radiator at the edfe of the pulley. Using this as a reference mark, rotate the engine until the pin points to the zero mark on the pulley.

Now, the distributer rotor should be pointing to number one on the dist cap. Try installing your plug wires and attempt to start. If you get a shotgun backfire you are 180 degrees out. What you will have to do is rotate the engine ONE complete revolution in a clockwise direction as viewed by standing in front of the radiator, and reinstall the plug wires. To turn the engine you can take out all the spark plugs to make it easier and then use a wrench on the power steering pump pulley.

You are only turning the engine 360 degrees clockwise and going back to the same mark on the pulley. There are two possibilities. If the first one causes backfire then the second one should work.

If you use the starter the engine will go more than one revolution and it will backfire again.

Good luck and let us know what you find.

Also, I would buy a set of Champion plugs for your car. The are a couple of dollars each and you won't believe how much a new set of clean plugs will help in this situation.

Oh, and try using one of your old plug wires in place of the wire that didn't show any spark. If you are getting spark at five places then the plug wire is surely to blame for the one that does not spark.