12 volt question

Hello all.
I was a heli mechanic in the navy so I have a 'decent' understanding of tools and mechanical repairs.
BUT.. I have came into the ownership of a 9N.. probably 1950+.
I was told by the P/O that this one had a 12 volt conversion but it started dieing after about 45 minutes. I did some research on the web and found that it might be the coil.
I went and got a 12V generic coil and installed it.
I have been very careful not to leave the ignition on at all when it is not running and it has started doing the die-after-it-is-warm thing again.

I read the article here about 12V conversions (ty for that). However, the article mentions using/retaining a 6 Volt coil.
I presumed mine was a 12v (when I did the replacement last fall) so that is what I purchased and installed... I also I noticed no ballast resistor on the wire to the ignition as I replaced the coil. This and a lot of ignorance about the 9N lead me to think I was doing fine installing a 12 volt coil.


I guess my questions are:
A) Did I do the right thing installing a 12Volt coil?
B) Does a 12 volt setup with a 12 volt coil need a ballast resistor, if so which one or which value/rating do I use?
C) Is the point gap also .15 for the 9N?

Thank you in advance for this free forum to ask for help and your time.


AF

With a 12 volt conversion and a 12 volt coil - you still need the OEM ballast resistor to keep from overheating the coil. Witha 12 volt conversion and a 6 volt coil you need the OEM ballast resistor plus a step down resistor. The point gap on the front mount dist is .015.

(quoted from post at 15:13:13 06/28/10) Hello all.
I was a heli mechanic in the navy so I have a 'decent' understanding of tools and mechanical repairs.
BUT.. I have came into the ownership of a 9N.. probably 1950+.
I was told by the P/O that this one had a 12 volt conversion but it started dieing after about 45 minutes. I did some research on the web and found that it might be the coil.
I went and got a 12V generic coil and installed it.
I have been very careful not to leave the ignition on at all when it is not running and it has started doing the die-after-it-is-warm thing again.

I read the article here about 12V conversions (ty for that). However, the article mentions using/retaining a 6 Volt coil.
I presumed mine was a 12v (when I did the replacement last fall) so that is what I purchased and installed... I also I noticed no ballast resistor on the wire to the ignition as I replaced the coil. This and a lot of ignorance about the 9N lead me to think I was doing fine installing a 12 volt coil.


I guess my questions are:
A) Did I do the right thing installing a 12Volt coil?
B) Does a 12 volt setup with a 12 volt coil need a ballast resistor, if so which one or which value/rating do I use?
C) Is the point gap also .15 for the 9N?

Thank you in advance for this free forum to ask for help and your time.


AF

Click to expand...

ou say, "generic coil" which conjures up in my mind, a round can coil such as would have been on the side mount 8Ns, and you also say 9N, 1950+, which can't be, because 9Ns ended production in 1947.
If you have a later side mount 8N with a round can coil, then there is a good chance that what you were sold as a "12v coil" is supposed to be used with a ballast resistor. There are a few coils that can be used on 12volts without a ballast resistor, the IC-14SB being one for sure and I believe also the CarQuest #26321 & BWD E40. There are likely a few more, but most of the coils sold as "12v coils" actually are intended to be used with a ballast resistor & need one.

9N production stopped in 1942 and then the y made the 2N. But me thinks you just forgot that part LOL

Thank you for the fast reply!

Aha! My bad it says 8N-B right on it.
Memory here is not so great, apparently.
Obviously, I really do not know a lot about this one.

This is where I messed up.. the new one says "resistor required", but I saw no resistor on the tractor and put it on anyhow.

I think I can find one of the resistors you listed but do you think I will need a new coil again?

image of the coil/distributor is enclosed. Maybe we can identify this one's year as well.

9N 1939 to 1942. 2N 1942 to 1947. 8N 1948 to 1952. The 9N and 2N both have 3 speed trannys and the 8N a 4 speed.
So what ship where you on and when. I was on the JFK from around 1877 or 78 till 1980 when got out.
Now to your problem. If your is a front mount distributor which 9N and 2N and early 8Ns are then they do not really make a true 12 volt coil and you will need to do as H Cooke said

(quoted from post at 15:08:57 06/28/10) 9N 1939 to 1942. 2N 1942 to 1947. 8N 1948 to 1952. The 9N and 2N both have 3 speed trannys and the 8N a 4 speed.
So what ship where you on and when. I was on the JFK from around 1877 or 78 till 1980 when got out.
Now to your problem. If your is a front mount distributor which 9N and 2N and early 8Ns are then they do not really make a true 12 volt coil and you will need to do as H Cooke said

Click to expand...

103 years is simply TOO long to be on the JFK!! ^^

I was land based in Texas, billet # 8215 Search and Rescue.. I did land on the Lex once in the gulf for a medivac but I went EAOS in '85 rather than go to sea for three years.

I am hoping the picture helps you guys determine what the heck I am working on

*coils rather. Not resistors.

(quoted from post at 16:06:07 06/28/10) Thank you for the fast reply!

Aha! My bad it says 8N-B right on it.
Memory here is not so great, apparently.
Obviously, I really do not know a lot about this one.

This is where I messed up.. the new one says "resistor required", but I saw no resistor on the tractor and put it on anyhow.

I think I can find one of the resistors you listed but do you think I will need a new coil again?

image of the coil/distributor is enclosed. Maybe we can identify this one's year as well.

Click to expand...

I didn't list resistors. I listed coils that do not require a resistor. Fair chance the coil has permanent damage from heat, but you might get lucky and just add a resistor to your existing coil....just a ~$5 gamble.

Thanks again, JMOR.
Yea I meant to type 'resistor-less coils'.
I found a supposed O'Reilly counterpart to that Carquest E40 coil you mentioned.
They stated their number as 2-5025.
26.99 for house brand.
33.99 for a Borg-Warner.
*This was a direct cross reference by telephone and the chap at O'Reillys did not know what it really was ballast-wise.
I guess I can look at the O'Reilly coil and see if it says 'external resistor required'?
I hate to kill another one.

AF

Since you have a side dist engine, forget everything I said -- gap for the side dist is .025.

.025 it is.

Ok then:
Installed the new resistor-less coil this morning and by golly after about 45 minutes... it started surging and wanting to die so I decided to stop.
I am thinking the carburetor needs adjusting since it only runs with the choke pulled all the way?
To wit:
A previous issue was that it was not getting enough gas (as in drip-drip off the fuel line at the carb.. so last Fall I drained the tank and got some FOD out of the petcock assembly. I believe I have the fuel starvation issue resolved since it streams out very well now at the carb.
Went to a website and got data on adjusting the carb (noticed that the choke was closed) and nothing even close to the suggestions would work! I returned carb screws to where they were and I have been running it this way since and till recently it would do 'ok' (I have 2 acres and could do half of it.. wait a bit then finish the other half).

I presume this was a 'fix' for some unknown-to-me issue (running the tractor with the choke closed [pulled] all the way)? :?:

Ready to work on it, I just need some pointers since it was all but a basket case which barely ran when i got it.

I have noticed the rear exhaust gasket is leaking as well and I should be ordering that promptly.
I will add that once it starts surging... If I then turn off the PTO it seems to idle fine.

just found this:
'If you have a new round can coil for your 8N and it does not say BAT and DIST on the top of it, just remember, for a POSITIVE GROUND tractor, it's Positive Plus to Points, (PPP) the .+. wire goes to the distributor. Hooking it up backwards reverses the polarity & costs you about 25% of spark efficiency.'

Would my 12v conversion be negative or positive ground?

But I have had about 1 hour 20 minutes of total run time, today.
Running for less time that it ran before I put in the new coil, now (15 minutes).
Perhaps I am not to connect '+' to the ignition switch?

Would my 12v conversion be negative or positive ground?

Click to expand...

If you're using an alternator - It is most likely a negative ground. Just to be sure look at your battery posts. Non insulated flat braid cable going to the frame of the tractor means it's a negative ground.

thanks, DollarBill

I does have an alternator but there is a normal automotive type insulat4ed ground going from the battery negative post to the frame.

If that is a 'Negative Ground' I can presume that the '+' post of the coil does go to the ignition switch, then?

If that is a 'Negative Ground' I can presume that the '+' post of the coil does go to the ignition switch, then?

Click to expand...

Yes sir, you are correct.

My new coil is installed correctly, then.
whew..

:/ now onto why it might still be dieing after 20 minutes of use.

(quoted from post at 05:10:58 06/30/10)
My new coil is installed correctly, then.
whew..

:/ now onto why it might still be dieing after 20 minutes of use.

Click to expand...

>>bump (sigh)

(quoted from post at 22:20:02 06/30/10)

(quoted from post at 05:10:58 06/30/10)
My new coil is installed correctly, then.
whew..

:/ now onto why it might still be dieing after 20 minutes of use.

Click to expand...

>>bump (sigh)

Click to expand...

wow.. ok then.
I guess I can drive it for 20 minutes and whine about it to anyone that asks why I get off of it after 20 minutes.
At some point, one has to ask themselves: "DO I just get rid of this since I cannot get much help online".
I feel like it is a glorified Briggs engine.. It came with the farm we bought. I just do not know anything about its' maintenance history and why it ended up tuned the way it is tuned.

I have a new 60" Deere mower deck for it (2300.00), two blades and a grass sweeper. It also has two brand new rear tires.
I need something which will mow the entire yard in one afternoon.
anyone interested in this relic?
Located in Central MO.

AudioFreq

A search of the archives turned up these troubleshooting steps which may fit your problem.

[color=darkblue:c9be766b80][b:c9be766b80]Runs for about 15-minutes and quits:[/b:c9be766b80][/color:c9be766b80] Restarts after about 30-minutes cool down = BAD IGNITION SWITCH, jumper across switch to test, and if problem goes away, replace ignition switch.

[b:c9be766b80][color=darkblue:c9be766b80]Runs for about 30-minutes and quits:[/color:c9be766b80][/b:c9be766b80] Restarts after 1-hour cool down = BAD IGNITION COIL, replace it. Next time it does this, check quickly for spark. Get an old plug, open the gap to 3/16, ground it to a rust & paint free spot on the head, turn the key on & crank the engine. You have three possibilities: no spark, weak and/or intermittent yellow spark, or a bright blue spark.

Sorry for not responding but I'm not the best when it comes to electrical problems and I have no experience with 12 volt conversions.

Run it until it quits and then check the color of your spark as indicated above.

Don't give up - You can figure it out. Just post back with your results for more help. You may have a faulty coil even though it is brand new. Tell us what the spark looks like when it quits.