8N Won't Start

Denna

Member
1949 Ford 8N will not start.

When attempting to start, there's a buzzing noise, but it never starts or turns over.

The following parts have been replaced:

12V starter with drive

Ignition switch

Distributor tune up parts

The battery reads 12.3V, but when attempting to start, the reading drops to 11.7V.

The battery has been connected to a jump starter, but that didn't change the situation.

Any ideas where to go from here ?
 
Does the starter spin? If not, jump the solenoid or jump directly
to the starter from the jumper pack. Make sure its in neutral.
 
" When attempting to start, there's a buzzing noise, "

That would be the solenoid. It is making a noise because of low voltage. That is likely caused by:

1. A weak battery (charge it per tip # 60 & check it per tip # 49))

2. Dirty grounds/connections (remove the cables & clean the connections)

3. Bad cables or incorrect sized cables (replace them - see tip # 41)

4. Bad ground between the starter & the block. (pull the starter away from the block & clean the mating area - see tip # 36)

" The battery reads 12.3V"

I can get 12.3 volts out of flashlight batteries. You need to make sure the battery is fully charged & then check it w/ a hydrometer (tip # 49) or take it to a shop & get it load tested.

" The battery has been connected to a jump starter,"

That's very dangerous.

See tip # 43 for the safe & correct way to do that.

Post back w/ more questions or results.
75 Tips
 
You can jumper across the solenoid by connecting one end of a
jumper cable, say the red end, to one side and the other red end
to the other side. Expect it to spark and possibly cause damage
to the threads on that last connected side of the solenoid.
Make sure its in neutral.

You can use the jumper pack by connecting one lead to the starter
terminal and the other to a good ground on the tractor frame, then
turn the jumper pack on. Again, make sure its in neutral.

Using a spare battery, connect one lead of the jumper cables to the
starter terminal, say red, and the other end to the jumping battery
positive. Then connect the black one to the jumping battery negative
then touching the other black end to the tractor frame.
I can't stress enough making sure its in neutral.
You will be bypassing the neutral safety switch and could get run over!
 
I just had this happen to me. After checking to make sure all
connections were bright and tight and had battery checked I
replaced the solenoid. Now she works great.
 
Replaced the solenoid.

Still have same problem.

When using a test light:

To battery positive terminal = Light

To solenoid post connected to battery positive terminal = Light

To other 3 solenoid posts, starter and distributor = No light

When using a test light, does the ignition have to be turned over at the same time ?

The solenoid, starter, ignition switch and battery cables are new.

After turning the ignition a few times, the negative and positive battery cables get warm.

How can I test the wires that are connected to the solenoid ?

Or should I be looking elsewhere ?
 
"To other 3 solenoid posts, starter and distributor = No light"

The original 8N solenoid only had three terminals.
It mounted on top of the starter with the small terminal pointed
in toward the engine block, not out where it is easy to get broken.

If you have the original wiring using the neutral safety thumb
button to start it then it sounds like you have the wrong solenoid.
One for a car/truck or a later model tractor, not for an 8N.
 
The tractor had been converted to 12 Volt.

I purchased a new 12 Volt solenoid from Yesterday's Tractor. It has 4 posts.

The previous solenoid was 12 Volt, so I transferred the wires to the new solenoid onto the same places.

There was a wire that was connected to the post nearest the solenoid's starter post. However, it wasn't connected to anything and I didn't see any place it could be connected to.

Perhaps it was leftover from a 6 Volt solenoid in the past that connected to a 6 to 12 Volt resistor.

I don't have an electrical wiring diagram for a 1949 8N, so it would be helpful if someone could point out what wires connected to the solenoid posts.
 
Is your tractor wired for a key start (like a car), or the original foot button start? These require different solenoids.

The original solenoid works when the control wire is grounded (which the foot button does). A key start solenoid works when the control wire is energized (it gets voltage when you turn the key to "start").

-Paul
 
Paul,

It's a key start ignition switch.

Is the control wire the one that connects to the solenoid post that's connected to the positive battery terminal ?
 
Ok, we need to take a look at what you have.
12V conversions can be done many different ways, including the
key switch that was done on yours apparently.
I don't like those because it eliminates the neutral safety switch.
However, the only way to know for sure what you have and why
its not working is to trace the wires so we know what you have
wired to where. Probably need the solenoid part number and the
key switch part number or terminal layout as well. Not all 4 post
solenoids are the same and there are many switches.

Personally, I would put the NS switch back in the circuit. I think
its safer and simpler, plus there are many wiring diagrams out
there for exactly how to do it.
Forum member JMOR has done some extensive work creating
pictograms for about every situation there is on an N with NS.
If you want to go that route, here's one of his diagrams that I
think fits your needs. He has one for the 3 wire alternator setup
as well. You can Google "wiring diagrams by JMOR" and find all
of them easily.
Post back and let us know what you decide.

mvphoto11638.jpg
 
(quoted from post at 17:08:21 10/02/14) Paul,

It's a key start ignition switch.

Is the control wire the one that connects to the solenoid post that's connected to the positive battery terminal ?

The control wire is the one that goes to the key (in your case) or to the foot button (as in the diagram that Royse posted). It's a small wire--not the large diameter wire going to the battery.

So the question now is *which* solenoid you bought. I'm no expert on solenoids, but a quick Googling seems to indicate that there are different kinds of four-post solenoids, and they may be wired differently. On all of them, the big terminals go to the battery on one side and the starter on the other. One of the small terminals is connected to the key start. It's the other that may vary.

-Paul
 
Here's the link to the solenoid purchased from Yesterday's Tractors.

http://www.yesterdaystractors.com/311006_Starter-Solenoid-12-Volt_2875.htm

Also, the battery was tested at Autozone and they said it was good.
 
And this is the key ignition switch.

http://www.amazon.com/Universal-Switch-Tractors-8N-3679C-9900-9048/dp/B0081SC7O0/ref=sr_1_2?ie=UTF8&qid=1413131390&sr=8-2&keywords=ford+8n+ignition+switch
 
Royse,

Would you post a picture of your 8N's electrical wiring where the battery is ?

I purchased the 311006 solenoid from Yesterday's Tractors because the electrical system was converted to 12v.

On JMOR's electrical diagram PDF, page 6 appears appropriate.

According to a store that sells the 311006 solenoid, the wiring is completely different from 3 post solenoid. The battery and starter connections are reversed.

For months, I've yet to get this tractor started.

The starter doesn't start, nor does the solenoid click.

The battery shows over 13v.

Any help you could provide would be appreciated.
 
Denna, I will gladly get you pictures, I just need to know of what.
The switch you linked looks like the right two terminal switch
for the original wiring. It is just on or off, no "Start" position.

The solenoid you linked is not the right one for an 8N.
To get that one to work, you would need one small post, the "S"
one I think connected to the push button NS switch and the other
small terminal, "I" I think, connected to a keyed power source.
That solenoid doesn't care which side is battery and which is starter.

[b:caea5a53ea]This[/b:caea5a53ea] is the right one for an 8N. Mounts on the starter.
[b:caea5a53ea]This one[/b:caea5a53ea] will also work with the original wiring and NS switch
but mounts somewhere other than the starter.
I know they say 6V, but they work fine on 12V also.
Both of these require the battery to be hooked on the correct side.

Here are a couple of pictures of one of my 8N's using the NAA
solenoid. This one has a 9N starter in it. It doesn't have the
holes in the barrel to mount the correct 8N solenoid, so this
was the solution. At least until the starter gets replaced.

The wiring is still the same as JMOR's diagram. Page 6.

mvphoto13276.jpg


mvphoto13278.jpg
 
Royse,

Thanks for the quick reply and pictures.

When the tractor was purchased, the 3 post solenoid was installed across from the battery and under the steering wheel (like your second picture).

Since the starter was replaced with a 12v compatible model, will it matter which solenoid is used, 8N11450 or NCA11450A ?

I think this is the starter model that was purchased.

http://www.dbelectrical.com/p-11675-new-ford-tractor-starter-drive-2n-8n-9n-1939-1952-3109.aspx

How can you tell if there is a Neutral Safety installed ?

What are the Neutral Safety wires connected to ?
 
Either solenoid will work, they just mount differently.
On the 8N, the NS switch is the push button starter by the shifter.
It is mechanically blocked from being depressed except when in neutral.
It has only one wire which attaches to the small terminal on the
solenoid and provides ground to activate it when pressed.
 

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