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My 100-6 Won't Start

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hundredsixinsf

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Having some trouble starting my 100-6. It's all stock and was running before I changed engine oil and filter, installed new needle and seats in float chambers, installed new radiator and thermostat and changed gearbox oil. Now it won't start up. Fuel pump is working fine and I checked for spark at the points, after cleaning the points, rotor and cap. What's the next thing to check? It's definitely turning over, but won't start up.

Thanks,
Steve
 
Okay, I'll try again, submitted my suggestions once, Nada:

First to verify you've got good spark.

I recommend you remove the plugs, connect them to the wires, lay the threaded ends on a good ground, or connect a wire to the plug and ground. Have some one crank it over while you check for good spark.

An extension on the latter, is take one of the plugs out, insert a long screwdriver, tip end in the wire, hold the metal shaft of the driver on a good ground(valve cover hold down?) while some one cranks, keep cranking and lift the screwdriver away from the ground slowly. This should verify you've got a good strong bluewhite spark. make sure that you are holding the screwdriver by the plastic handle and not grounding yourself to the engine.

If you don't have spark, then pull the coil wire out of the distributor and use the screwdriver on it, same procedure as just above, this isolates to distributor/coil if no spark.

If you have good spark recheck the fuel feeds, make sure that your float bowls are getting filled. May have inadvertently covered a feed/vent fitting when working on the carbs.
 
Steve--

Did you check for spark at a plug?
 
hi steve, i think your problem is the fuel needle and seat in the carbs. they tend to stick espeially if its the tapered needle and not the gross jets. i would rap on the float bowl with a wrench or some other light tool to free them up and try seeing if you get fuel in there and it fires then. pull the float cover if that doesnt work and see what you have.
Randy
 
Thanks for the suggestions. I've tested for spark at the points, but not at the plugs. I've pulled all the plugs and cleaned them up. Then blew out the plug connectors. But nope, haven't tested for spark at the plugs. The engine was running fine a few months ago. Started everytime. So I highly doubt the plug wires are bad.

As for fuel, I started to remove the float bowl covers and could see fuel starting to seep out, so I'm almost positive the float bowls are full. The fuel needles and seats in both carbs are brand new. The seats are plastic and the needles are metal. I've got the pointed ends of the needle facing towards the cover and the flat part of the needle towards the float, which I'm assuming is the correct configuration. The only other thing I did was pull the small steel mesh filters and springs in the float chamber covers and cleaned them out. I put the spring in first and the mesh filters in next then screwed on the fuel line. I think that's correct as well.

I'll attempt to check for spark at the plugs as Ron describes above, but I'm all by myself. No helper. Is there an easy way to test for spark by myself? So connect the wire to the threaded metal part of the plug, right? Not to the spark plug contact. If so, where exactly do I look for a spark? Will the contact end of the plug just start sparking?

Thanks,
Steve
 
No helper. Is there an easy way to test for spark by myself? So connect the wire to the threaded metal part of the plug, right? Not to the spark plug contact. If so, where exactly do I look for a spark? Will the contact end of the plug just start sparking?

Steve--

You don't need one.

1. Disconnect one spark plug wire from its plug and roll back the boot so that the metal contact is visible.

2. Turn on the ignition key and hold the wire with insulated pliars in your right hand so that the contact is about 1/4" from the threaded tip of the plug.

3. With your left hand push the button on the back of the starter solenoid so that the engine turns over.

A spark should jump from the contact to the plug. If it doesn't suspect the rotor or coil.
 
One small additional tip is to make sure the car is in neutral. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
Try putting the old needles and seats back in and see if it will run.
Reproduction parts, depending on where they were manufactured, are not always good.
 
Doh, I may have tossed the old needles and seats Doug. I got the new stuff from Moss.

Michael, thanks for the clear instructions on the spark test. I'm a newbie at this, if you can tell. For your step 3 below, where is the starter solenoid located and what does the button look like?

3. With your left hand push the button on the back of the starter solenoid so that the engine turns over.

Thanks,
Steve
 
Steve -

Sounds to me like you have a bad rotor. Try checking for spark at the plug, not the points.

There are alot of badly manufactured rotors floating around. Try replacing your rotor.

If you want more info on the bad rotors that are flying around our favorite parts suppliers, have a look at this website, it will explain just about everything. Anything that looks like rotor #3 or #4 should be tossed to high heaven:

https://www.healey6.com/email%20postings/Rotor%20Comparison.pdf

Good Luck
 
Steve--

The starter solenoid is a cylindrical-shaped switch located on the right side of the engine bay against the firewall and alongside the bellhousing. You should see a large diameter wire coming to it from the battery and another large diameter wire going from it to the starter with another few smaller wires to it for the solenoid circuit. The back face of it is rubber and by pushing on it you will manually make the solenoid circuit and engage the starter. You should be able to push it by hooking a finger around it--you can also jump across the terminals with a screw driver but given the posture I have you in at this point it may seem kind of scary!

And yes, DO make sure the car is out of gear.
 
Thanks Michael. I'll give it a try today and let you know how it goes. I'll check for spark at the plugs today.

My rotor looks fine. Not cracked, fits nice and tight on the distributor shaft. I cleaned it up as well. It is the #2 labeled rotor.

--Steve
 
Steve -

If your rotor (or distributor cap) is cracked, you won't be able to tell by looking at it visually.

Can't hurt to swap the rotor as a double check anyway.

Good Luck
 
Ok, I just pulled the number three spark plug, left it connected to the plug wire and held the connector with a pair of insulated pliers. I had a friend push the starter button while I held the threaded metal part of the plug against the valve cover securement nut. I did see a spark, but not sure if it was a strong one or weak one, since I don't know what would be considered strong. But the spark was there. I turned over the motor a few more times and it almost kicked over a couple of times. But still won't stay started. I'm charging the battery to make sure it's strong and will replace the plugs as well, since they are a million years old. I did clean them all up very well though. Could the cause be a weak/bad coil?

Steve
 
Could very well be.

Strong spark will be blue/white and able to jump a gap, that's why I suggest you start with the plug/screwdriver grounded and lift it away from ground as someone is cranking. That way you will be able to "track" the gapping capability of the spark jump.

Weak spark will be dull yellow.
 
Does a coil just die? Or does it die out slowly over time? My car was starting fine just several months ago and has been stored in the garage since then.

The spark color was blue/white. Not dull yellow.
 
Based on my experience coils usually experience a sudden death at the most inappropriate time.---Keoke
 
Okay, by checking for spark at the plug, and getting a good spark there, you've verified the coil and rotor functionaliy.

Go afte the fuel.
 
I would review the procedure in changing the needles and seats. If it won't start and you have spark, it's got to be fuel.
 
hundredsixinsf said:
Ok, I just pulled the number three spark plug, left it connected to the plug wire and held the connector with a pair of insulated pliers. I had a friend push the starter button while I held the threaded metal part of the plug against the valve cover securement nut. I did see a spark, but not sure if it was a strong one or weak one, since I don't know what would be considered strong. But the spark was there. I turned over the motor a few more times and it almost kicked over a couple of times. But still won't stay started.
Steve
Click to expand...

Steve--

Since you have a spark and it sounds like the engine is trying to fire over but is not I turn my attention to the fuel system. Some of the questions that come to mind are:

1. Is there fuel in the bowls?
2. Are the floats shutting off fuel to the engine?
3. Can you smell fuel or does a spark plug appear wet after cranking for a while?
4. Is the fuel pump running and if so is it shutting off or slowing to an occasional click?
5. Is there an inline filter or filter in the pump that you have not checked?
6. And lastly and perhaps most importantly--is there fuel in the tank?
 
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