another 8n that wont start.

   / another 8n that wont start. #1  

Adj100

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Aug 15, 2011
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8n Front distributor

supposedly rebuilt about a year ago (looks like mostly a paint job and some gaskets) battery was old, distributor looks original etc.

Have a new charged battery in it. Starter spins it, but nothing more. Have verified I am getting sparks from all 4 plugs (with battery positive to ground) Best I can tell is 6v system.
Fuel to the carb (which I currenly have apart to clean, as questionable gas sat in it for a year)
Now the choke does have a penny brazed into it blocking the bottom half:confused:

(key appears to do nothing, as the starter runs with it or not)

If a cleaned carb does not work what should I try next?
 
   / another 8n that wont start. #2  
Fuel, air, spark, timing, and compression.

At least one is missing.

The timing or firing order could be off after a rebuild. Was it running after the rebuild, or did someone give up on it?

Bruce
 
   / another 8n that wont start.
  • Thread Starter
#3  
It was delivered from the shop and ran at least once, not sure how well, I wasnt there, and my father in law who drove it was in poor health, and has since passed on so it sat all last summer before we tried to start it again.

Did have the battery in negative ground for awhile, so not sure if that fried something. I do get sparks on all plugs, though not sure of the timing, how fast should it be turning/ sparking?

If the magneto/coil was fried I would get no sparks at all right?
 
   / another 8n that wont start. #4  
Are you checking the spark by grounding each plug and watching it jump the gap on the plugs, as they are intended to?

You mentioned about the key not doing anything because it cranks with the key in either position. This is normal. The key turns the power on to the coil and has nothing to do with the starter circuit.
 
   / another 8n that wont start.
  • Thread Starter
#5  
correct I am grounding the plug to the block. Definately getting sparks on all plugs.

Definately spinning as well, but no firing, barely audible putt once per revolution or less often.
 
   / another 8n that wont start. #7  
Check to be sure:
 
   / another 8n that wont start. #8  
Have a new charged battery in it. Starter spins it, but nothing more.

The starter spins....I am assuming you mean it is spinning the motor over??

Have verified I am getting sparks from all 4 plugs

Verify they ARE in the correct order mentioned in the previous post:thumbsup:

(with battery positive to ground) Best I can tell is 6v system.

Was the old battery 6v and positive ground? Does it have an enclosed generator, or a newer style aluminum-housed alternator?

Fuel to the carb (which I currenly have apart to clean, as questionable gas sat in it for a year)

This may help on your carb overhaul Yesterday's Tractors - Step by Step Carburetor Overhaul - 1952 Ford 8N

Fuel to carb is good. But it has to get from there to the engine in the right amount. Make sure the pilot jet and main passage way is clear. At the end of the article is some good tips for tuning.

And as another poster mentioned...are the plugs wet with fuel?? indicating that you are at least getting gas to the engine?

Now the choke does have a penny brazed into it blocking the bottom half:confused:

That shouldnt hurt anything, just allow it to "choke" a little better and suck up more fuel. Possibly indicating this tractor is close to needing an overhaul and has been getting hard to start???? once running though, that penny doesnt hurt a thing. Its kinda like the old trick with small motors and holding your hand over the carb to give a little more "choke"

(key appears to do nothing, as the starter runs with it or not)

Thats normal. The starter works without the key, and will crank and deliver fuel without the key, but the key feeds the coil to give it the spark. If you try starting without the key on, all you will do is flood it.

If a cleaned carb does not work what should I try next?


Verify all of the above. IF you are getting fuel in the right amount to the engine, and sparking at the right time, the only other thing it could be is lack of compression.

So, one you verify the carb is good after the rebuild, make sure you are getting spark to the plugs, NOT just the wires. You could have flooded it causing no spark at the plugs, or fouled the plugs.

If all that is okay, I think a compression test is in order:thumbsup:
 
   / another 8n that wont start. #9  
Any update for us???
 
   / another 8n that wont start.
  • Thread Starter
#10  
Got a set of new plugs, ordered gaskets for the carb and its soaking in carb cleaner, with the weather, probably will no be working on it again until the weekend, its not at my place.

Do have the battery here, sitting at about 6.25 volts.
Did feel compression when I had the plugs out and turned it over. Did not really seem to be too wet or fuel odor in the cylinders though which is why I went to the carb, but other then the bottom gasket I ripped when pulling it appart it did not seem to have any issues. (other then the drain plug on the bottom is rounded off and stuck in good.

Sealed generator, appears to be original type


Thanks for all the advice so far
 
 
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