VCCA Home Forums TECHNICAL - GENERAL Electrical - 6 volt '50 electrical... again!!

Shorting the end of the plug wire when attached to the plug should give a good indication of the effectiveness of the spark plug and the voltage being fed to the plug. If there is no discernible difference in engine speed then that cylinder is not firing correctly. It could be one of many reasons. Conversely if there is a drop in engine speed then the cylinder is at least operating.

When checking the spark intensity of the wire or spark plug the quality of the ground is a factor. Paint or corrosion at the point where the spark jumps or plug is grounded can be a factor. Also the conductor in the plug wire, condition of the wire ends, how far the wire is pushed into the socket, condition of socket on the cap, condition of the contact on the inside of the cap, crack in the cap can contribute to the observed weak spark.

So.....which cylinder has the weak spark, number one or number six?

Also, if you had a short your amp meter would most likely peg itself on the discharge side of the gauge.

A bad valve will not cause a weak spark. It will cause a miss on that cylinder.

Here's todays update... a step backwards! We took it for a twenty mile drive last night. It ran fine for the first half, and showed a charge on the amps. On the way back I decided to turn the lights on. It started to sound like it was cutting out, or not getting a good spark. It kept running, but was hesitating, and felt different. I drove it home, put it in the garage, and tried to restart it... and it just cranked and wouldn't fire again. Power is down to the coil. Still showing 6+ volts on the battery and the starter. Also, I could hear a valve sticking more... a puffing sound at the exhaust. Or maybe it's not a valve, and it's just that cylinder that's not firing right puking it's gas out?

The firing order in my book shows #1 at the firewall, and #6 at the front of the car. It's #6 that's the weak one.

Oh, and it's a 3 speed, Richard... any ideas where I go from here?

That could be your problem! If your book actually says that the number one cylinder is in the back of the engine then you need to throw your book away! Either that or you might have read the book wrong because if what you said is true then you have the firing order backwards!! The number one cylinder is in the front of the engine next to the radiator and the number six cylinder is at the back of the engine, next to the firewall. Not the other way around! Since you may have your firing order backwards (based on what you said in your post) then your present firing order is 6-2-4-1-5-3.

Starting from the front of the engine the firing order is 1-5-3-6-2-4, with the number one spark plug wire being at the six o'clock position on the distributor cap. Again, the number one cylinder is in the front of the engine and the number six cylinder is in the back of the engine.

Maybe I'm talking out of my butt again! I'll go have a look...

Okay... I had a look. The book says the order is starting from the furthest point (6oclock) on the distributor from the motor, and the order is 1-5-3-6-2-4. I assumed that #1 was against the firewall because that's how it looks when you are standing over the distributor, and if you look back to page one of this thread, you'll see that at 6oclock on my '51 is the plug lead for what I thought was cylinder #1! I'll have to look for mark on the flywheel and set it up again... but I'm pretty sure that if I had it wrong, the car wouldn't run... as all the cylinders would be firing at the bottom of the stroke, right?

Never assume anything or you will get yourself screwed up. As we mentioned to you before, the number one spark plug wire is at the 6 o'clock position on the distributor, which is the tower at the bottom of the distributor next to the inner fender (the same as on a clock). The number one spark plug wire goes from that tower to the number one cylinder which is at the front of the engine. Then, clockwise, the next spark plug wire would go to number 5, which is the fifth cylinder back from the front of the engine and so on. If you don't have your spark plug wires set up in the order described (1-5-3-6-2-4) from the front of the engine to the back then you have it wrong. It is possible to have the wires in the correct order and the distributor 180 degrees out.

If you are in doubt about what you are doing, then you might get a professional mechanic to help you set up the firing order and the timing. Since you apparently have your firing order 180 degrees out, that is no doubt why your plugs are sooty and you can't start the car.

Good luck!

The important thing is that you have everything lined up to run as it is. It looks like you have the distributor 180 off, but the plug wires are where they need to be to do the job.

If you want to get it right, line up the #1 cylinder on compression and the timing mark. Then pull the distributor and turn it 180 degrees and put it back. Watch the rotor as you pull it out, because you want it 180 from the point where it stops turning as you lift the distributor out. Once you've done that, put the cap back on and starting with #1 down at the 6 o'clock position, connect the cables by firing order going clockwise.

Time it, button everything down and take it for a drive. I think the rest of your troubles will go away after a good hard run.

WRONG, number One is at the front of the engine

I don't doubt you guys one bit... It just seems odd to me that they wouldn't mention which cylinder is #1 in the manual! I can't be the only one that's screwed that up before!

So I'm guessing that the '51 has the distributor turned 180 degrees but the plug wires are also turned as well. The car has run perfectly like this for 45+ years that the motor has been in it. I'm not going to mess with it!

I think the '50's distributor has been turned as well, and the wires as well, but they may not be lined up 100%. I'm going to have to get a timing light to set it up properly. My concern is... would that timing being out affect the car on starting the way it is, ie: causing different electrical loads going to the starter and coil? I had it out again today, and it seems to start just fine when it is cool, then back to not starting when it's hot! Putting a direct wire to the coil from the battery makes it fire right up...

As I mentioned before, the distributor doesn't really care what position it's in as long as the plug wires go in the right towers to make up for it and it gets timed right. Your plug wires are in the correct sequence. The timing may be off far enough to make it hard to start when hot, BUT

I really think that you have a problem with your starter. Have you gone to the web page I sent and done the checks on it? It sounds to me like it is drawing too many amps; that problem gets worse when the engine/starter is hot.

I haven't done that yet.... I'm going to do that when I get a whole day to work on it. I'm really kind of against taking it to a mechanic as well. I think it's only getting harder to find ones that know these old cars, so I really want to learn myself. I've learned so much in the last few weeks! That's where you guys come in... Thanks!

Yes.

Also, keep in mind that the valve timing has a relationship to the firing order as well.

You should probably start fresh and then go from there. That is to say, you should have the number one cylinder (which is in front not in the back) on compression stroke, the timing mark lined up with the pointer, the rotor on the distributor pointing to the number one tower on the distributor cap and the firing order 1-5-3-6-2-4 in a clockwise rotation from that point.



The timing chart that I have shows a layout of the cylinders and that the front cylinder is number one. Sounds like you might need more literature on your car.

You would think that the Shop Manual would have such info, but mine for 1940 doesn't. They probably felt that people using the manual would already know such things. I think that when Motors and others started writing aftermarket manuals they went into more detail on such things, because they were writing for other than manufacturer mechanics and laymen. I sure miss my old Motors manual, but that's another thing that disappeared over the years.

So, what manuals do we need for sufficient info on our cars, and where do we get them?

You can never have too many manuals and a variety is even better. I have found that in many cases my Motors manuals give more information than the factory shop manual....for one...the layout order of the cylinders.

Manuals can be purchased on eBay, from the Filling Station, from swap meets, and a really good source would be from literature dealers.

YO Brewster! Got an up date for us yet? I was thinking about your hot start problem. Does it crank okay or sound like the battery is low? Have you tried holding the gas pedal to the floor for a hot restart? It could be a starter problem, timing or carburation.

Let's get this thing fixed for some touring! Or I suppose you might be out there doing that now?

I'm on a bit of a break from it right now. I had the '51 out for a S. Ont. Region tour on Saturday, and the centre distributor-coil wire was shorting. We had to replace it, and Randy Petitt was able to come up with one for me. It was one I swapped over from the convertible last week, so I'm going to make sure that both of them are not bad! I think the next step is going to be get the timing right, and the distributor turned right, to eliminate that as a symptom. Also going so check the valves, as I think one is sticking. Kind of big job type stuff, so I'll need to leave it till I have a couple days off. The town's Fall Fair is next Saturday, and 2 blocks from my house, so I may take it to the car show there next week.