1950 8n starts then dies

[Uncle Theo]

Hello, I am a new member here. Thanks for the opportunity to join in.
I have a 1950 Ford 8N,which I have had for 10 years. I converted it to 12 volt and it has served me faithfully since.
My problem is, after letting it sit for 2 weeks while I was gone, it will start, run for a minute or so then die. I have put in new points, condenser and coil.
I also replaced the fuel shut off valve/ sediment bowl and carburetor (both which were needed anyway).
After all that it still dies, no change.
Any thoughts?

 

[wore out]

Instead of blindly throwing parts at it, grab a spark tester and note if it loses spark when it quits running properly and is coasting to a stop.

That will tell you if it is the ignition system or the fuel system that needs attention.

 

[HFJ]

(quoted from post at 16:27:08 04/19/23) Hello, I am a new member here. Thanks for the opportunity to join in.
I have a 1950 Ford 8N,which I have had for 10 years. I converted it to 12 volt and it has served me faithfully since.
My problem is, after letting it sit for 2 weeks while I was gone, it will start, run for a minute or so then die. I have put in new points, condenser and coil.
I also replaced the fuel shut off valve/ sediment bowl and carburetor (both which were needed anyway).
After all that it still dies, no change.
Any thoughts?

my 2N has a rusty tank. when i got it, the reserve pickup on the sediment bowl was already plugged. i replaced it a while later. i was barely out of the pole barn and it quit running. turned out the new sediment bowl assembly had already plugged. i mention this because the symptoms match. the tractor ran just fine until i ran out of gas in the float bowl.

like wore out suggested, check for spark the moment it dies. i'd recommend an adjustable gap spark tester, set to a quarter inch. test lights will often give a false positive to a uselessly weak spark.

if it passes the spark test, pull the plug out of the bottom of the float bowl. with sediment bowl valve open and plug removed from carb, fuel flow should fill a pint jar in ~ 2 minutes. don't let a strong flow for a few seconds fool you, it could just be the bowl itself draining.

 

[Mike Groom]

Take the gas cap off and try it. If it stays running with the cap off a muddawber may have made a nest on the vent on the hump of the gas tank. Just a thought it happened to me once.

 

[Uncle Theo]

This post was edited by Uncle Theo on 04/19/2023 at 04:16 pm.

 

[Uncle Theo]

I'll check that out, thank you.

 

[Uncle Theo]

Thanks for the suggestion. I'll try that.
If its fuel it should be an easy fix. If its spark, that leaves more questions.

 

[HFJ]

i'd have bet a hundred bucks there was no way the reserve pickup on the new assembly could have plugged already. i had literally just started it back up after replacing it.

i'd have lost that hundred. on the plus side, tractor repairs don't get much easier than pouring more gas in the tank

 

[JMOR]

(quoted from post at 20:00:38 04/19/23)
i'd have bet a hundred bucks there was no way the reserve pickup on the new assembly could have plugged already. i had literally just started it back up after replacing it.

i'd have lost that hundred. on the plus side, tractor repairs don't get much easier than pouring more gas in the tank

ith only 2 gallons of liquid and 8 gallons of air in the tank and engine running for 2 minutes, the small volume ( ~1 TO 2shot glasses of gas) of change in tank, suggest to me that tank vent is not your problem. Sediment bowl clogged passages, maybe on an old dirty/rusty tank, but for now I would do as wore out suggested and look for spark immediately at point it dies..

 

[Leroy]

I will ask WHY DID THEY NEED RPLACING? What happened to them. Do you still
have the parts you took off? If you do take apart and clean and rebuild and
put back, Unless they were broken no need to replace, just clean and repair
kit. What I hear on this site is the new replacement carbs are junk out of
box. And things can plug in a minute. Did you know there is a third screen
in the carb? I think you just expanded your problem putting the new pars on.

 

[Uncle Theo]

(quoted from post at 11:11:57 04/20/23) I will ask WHY DID THEY NEED RPLACING? What happened to them. Do you still
have the parts you took off? If you do take apart and clean and rebuild and
put back, Unless they were broken no need to replace, just clean and repair
kit. What I hear on this site is the new replacement carbs are junk out of
box. And things can plug in a minute. Did you know there is a third screen
in the carb? I think you just expanded your problem putting the new pars on.

I replaced the shutoff value because the screen was all but gone. The carburetor because I've been wanting to do that for a while and the points condenser and rotor because they were due.
I am certain that fuel is not the problem. I put a spark tester on it today and it is loosing spark as it dies.
PS. I never throw anything away.

 

[JMOR]

(quoted from post at 14:31:14 04/20/23)

(quoted from post at 11:11:57 04/20/23) I will ask WHY DID THEY NEED RPLACING? What happened to them. Do you still
have the parts you took off? If you do take apart and clean and rebuild and
put back, Unless they were broken no need to replace, just clean and repair
kit. What I hear on this site is the new replacement carbs are junk out of
box. And things can plug in a minute. Did you know there is a third screen
in the carb? I think you just expanded your problem putting the new pars on.

I replaced the shutoff value because the screen was all but gone. The carburetor because I've been wanting to do that for a while and the points condenser and rotor because they were due.
I am certain that fuel is not the problem. I put a spark tester on it today and it is loosing spark as it dies.
PS. I never throw anything away.

y (right or wrong) interpretation of, "it is loosing spark as it dies.", is that spark is gradually going away. Is that what you mean to say, or is it more like it dies and immediately there is no spark? Gradual does not sound right to me.

 

[Uncle Theo]

(quoted from post at 11:47:04 04/20/23)

(quoted from post at 14:31:14 04/20/23)

(quoted from post at 11:11:57 04/20/23) I will ask WHY DID THEY NEED RPLACING? What happened to them. Do you still
have the parts you took off? If you do take apart and clean and rebuild and
put back, Unless they were broken no need to replace, just clean and repair
kit. What I hear on this site is the new replacement carbs are junk out of
box. And things can plug in a minute. Did you know there is a third screen
in the carb? I think you just expanded your problem putting the new pars on.

I replaced the shutoff value because the screen was all but gone. The carburetor because I've been wanting to do that for a while and the points condenser and rotor because they were due.
I am certain that fuel is not the problem. I put a spark tester on it today and it is loosing spark as it dies.
PS. I never throw anything away.

y (right or wrong) interpretation of, "it is loosing spark as it dies.", is that spark is gradually going away. Is that what you mean to say, or is it more like it dies and immediately there is no spark? Gradual does not sound right to me.

Seems as if the spark gets weaker just before it dies.

 

[Tim PloughNman Daley RIP]

Did you test old parts first? Just replacing old parts with new without performing true root cause problem solving methods is illogical. All major OEM components can and
should be rebuilt before buying any new aftermarket unit; most all are made in Cheena now and are junk. Troubleshooting the root cause problem is the proper procedure and
avoid guessing. There are tests you can do for this. Email me for more detailed information, too lengthy to list here. Incorrect wiring is 99.98% of all non-starting
issues, with 12V conversions being a majority of them.


Tim Daley (MI)

 

[JMOR]

(quoted from post at 19:26:13 04/20/23)

(quoted from post at 11:47:04 04/20/23)

(quoted from post at 14:31:14 04/20/23)

(quoted from post at 11:11:57 04/20/23) I will ask WHY DID THEY NEED RPLACING? What happened to them. Do you still
have the parts you took off? If you do take apart and clean and rebuild and
put back, Unless they were broken no need to replace, just clean and repair
kit. What I hear on this site is the new replacement carbs are junk out of
box. And things can plug in a minute. Did you know there is a third screen
in the carb? I think you just expanded your problem putting the new pars on.

I replaced the shutoff value because the screen was all but gone. The carburetor because I've been wanting to do that for a while and the points condenser and rotor because they were due.
I am certain that fuel is not the problem. I put a spark tester on it today and it is loosing spark as it dies.
PS. I never throw anything away.

y (right or wrong) interpretation of, "it is loosing spark as it dies.", is that spark is gradually going away. Is that what you mean to say, or is it more like it dies and immediately there is no spark? Gradual does not sound right to me.

Seems as if the spark gets weaker just before it dies.

ultiple reasons for instant total loss of spark, but gradual weakening is generally due to heat, BUT 1 -2 minutes is not enough for some item with the mass of a coil to get hot.....maybe a poor connection along the way?

 

[Jim L WA]

Hi Uncle Theo, welcome to the forum. As you can see, there are plenty of knowledgeable folks on here that want to help.
Here is my suggestion to do first if you really think it's an ignition issue. Run a jumper wire from battery to the ballast resister (bypass the ignition switch). If that doesn't help, then move that jumper to the coil side of the ballast resister and see if that helps. Don't run it very long like that, just see if it runs longer than a couple of minutes.
Let us know the results.

 

[JMOR]

(quoted from post at 12:40:37 04/21/23) Hi Uncle Theo, welcome to the forum. As you can see, there are plenty of knowledgeable folks on here that want to help.
Here is my suggestion to do first if you really think it's an ignition issue. Run a jumper wire from battery to the ballast resister (bypass the ignition switch). If that doesn't help, then move that jumper to the coil side of the ballast resister and see if that helps. Don't run it very long like that, just see if it runs longer than a couple of minutes.
Let us know the results.

should have added earlier, but here it is now. 1 -2 minutes is about how long it will run even if you filled the float bowl and never even connected a fuel line.

 

[Tim PloughNman Daley RIP]

Mike - sent you a msg...

Tim Daley (MI)

 

[Uncle Theo]

(quoted from post at 06:46:40 04/21/23)

(quoted from post at 19:26:13 04/20/23)

(quoted from post at 11:47:04 04/20/23)

(quoted from post at 14:31:14 04/20/23)

(quoted from post at 11:11:57 04/20/23) I will ask WHY DID THEY NEED RPLACING? What happened to them. Do you still
have the parts you took off? If you do take apart and clean and rebuild and
put back, Unless they were broken no need to replace, just clean and repair
kit. What I hear on this site is the new replacement carbs are junk out of
box. And things can plug in a minute. Did you know there is a third screen
in the carb? I think you just expanded your problem putting the new pars on.

I replaced the shutoff value because the screen was all but gone. The carburetor because I've been wanting to do that for a while and the points condenser and rotor because they were due.
I am certain that fuel is not the problem. I put a spark tester on it today and it is loosing spark as it dies.
PS. I never throw anything away.

y (right or wrong) interpretation of, "it is loosing spark as it dies.", is that spark is gradually going away. Is that what you mean to say, or is it more like it dies and immediately there is no spark? Gradual does not sound right to me.

Seems as if the spark gets weaker just before it dies.

ultiple reasons for instant total loss of spark, but gradual weakening is generally due to heat, BUT 1 -2 minutes is not enough for some item with the mass of a coil to get hot.....maybe a poor connection along the way?

I have tried all of the above suggestions and I do appreciate the input from all of you. Today I replaced the wire to the coil, the wire frm the the coil to dist. and the coil wire. All with no change to the problem.
The thing that has me baffled is, after it dies I can immediately restart it. Which leads me to believe it's not fuel but spark.
I'm at a loss as to what it can be. I can't beieve after 70 plus years of these tractors being in use that this is the first time this issue has surfaced. hopfully when it is remedied there will be someone else we can enlighten.

 

[soaked]

IIRC, a fellow posted his 8n
sidemount ran 30 sec to a min,
then died, then restarted. Same as
yours. Thread went on and on.
He swapped cap and rotor to fix.
Never said if one or the other was
the remedy.