Ford 9N Keyed Switch and safety interlock cradle questio

I have a Ford 9N. Told at purchase it was a 1939 but probably a 1941 since keyed switch is on left side of steering column. Tractor has been sitting a couple of years but previously ran. Can't get it started now. Intermittantly my amp meter does not show a negative deflection when the key is turned on. Does this imply the key switch is bad? Also my push button starter switch has to be pushed down real hard and only sometimes turns over the engine, only if I see a negative deflection on the amp meter. I'm afraid my safety interlock cradle may be busted. If so, how do I fix it? Probably not going to be easy. I am getting a good spark at the plugs but engine does not fire. Fuel is getting to the carb. I don't know when the carb was last cleaned.

(quoted from post at 18:22:15 12/03/22) I have a Ford 9N. Told at purchase it was a 1939 but probably a 1941 since keyed switch is on left side of steering column. Tractor has been sitting a couple of years but previously ran. Can't get it started now. Intermittantly my amp meter does not show a negative deflection when the key is turned on. Does this imply the key switch is bad? Also my push button starter switch has to be pushed down real hard and only sometimes turns over the engine, only if I see a negative deflection on the amp meter. I'm afraid my safety interlock cradle may be busted. If so, how do I fix it? Probably not going to be easy. I am getting a good spark at the plugs but engine does not fire. Fuel is getting to the carb. I don't know when the carb was last cleaned.

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You see a negative deflection when the starter switch energizes the starter causing it to draw the battery voltage down.

The starter interlock is mechanical and the pushrod that operates the starter switch can and does wear on the end. Then the worn rod does not reliably push the starter switch fully closed and you have your situation. If that is your problem its a simple, inexpensive, and easy fix.

TOH

Turning the key on will only show negative if the points are closed. If the points are open there is no draw on the battery until you engage the starter.

Mark

(quoted from post at 17:59:31 12/03/22) Turning the key on will only show negative if the points are closed. If the points are open there is no draw on the battery until you engage the starter.

Mark

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Thank you Mark. That explains why I only see the absence of a negative deflection on the amp meter intermittently.

(quoted from post at 19:59:31 12/03/22) Turning the key on will only show negative if the points are closed. If the points are open there is no draw on the battery until you engage the starter.

Mark

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Where was my brain on that one?

Thank you TOH. I will check the rod connected to the starter switch to see if it has eroded and replace as required. When I remove the push button situated on the gear box lid and look into the hole I see the ends of what I take to be the interlock cradle. There actually are two pieces to the cradle both having convex ends that can be separated by moving them with a screw driver. The long rod on the bottom of the push button goes between those two pieces and there is a collar on the push button rod that I presume moves the cradle when the button is pushed down for starting. I presume that is the way the "cradle" is supposed to be/look? I'm just hoping the cradle is not broken. The spring loaded push button seems to be working just fine. Sorry to bother you with these details. I've driven a lot of both 8N and 9N Fords as a boy but never worked on them. My grandson and I are trying to get my 9N running again so I may end up bugging you fellows from time to time.

We all forget to put it in gear sometimes.

Mark

I'd start out cleaning all the thick wire connections from battery to starter real well: bat terminals, bat ground, bat to starter switch, starter switch to starter. Tractor that has been sitting a long time should be done anyway.

You can quickly check bat/starter ground, by running a jumper cable from the battery's un-grounded side to the starter post (not sure if you are set up + or - ground). BE SURE TRACTOR IS IN NEUTRAL FIRST. If starter turns over well bat/starter ground is good. That is assuming you don't have a wonky starter........

Concerning the starter button you have to be sure the shifter is positioned in neutral for it to engage the switch, try giving it a wiggle when you hit the starter button.

You can jumper across the starter switch to see if it turns over. If it does then it could be the switch or the mech from the starter button. AGAIN BE SURE IT'S IN NEUTRAL. Might save you taking all that stuff apart.

I've had my switch go bad.

Once it turns over reliably then start checking the ignition and fuel systems.

Lots of info on that here, and people here will walk you through that.

Do you have shop/service manuals? The IT one is a good start and/or get the Ford one.

AZ Rancher , To repair the starter switch behind the dash ,remove the switch ans solder or JB Weld a couple flat washers or penneys to the switch button top to extend it to make up for the ware in the linkage so it pushes the switch more.
The amp gauge will deflect only if the points are clean and adjusted correctly.Then you should have spark to all 4 plugs and if so drain and check fuel flow with gas on at bottom of the fuel bowl ,1 pint in 2-3 minutes. Then try some starting fluid in the carburetor intake while cranking it over to see if it will start.

Thank you Den and Mad Farmer. All you fellows have given me some really good pointers to work with and I will follow through on all of them. Due to a long "honey-do" list to deal with before Christmas it likely will be a couple of weeks before I can get back to the Ranch where I have my tractor. To answer your questions, my 9N does have a negative ground system and I do have the Ford Manual to read, although you guys have been more helpful. I just purchased a Commercial grade 6 Volt battery from NAPA with 785 cranking amps and it did turn over the engine briefly but I could not keep it cranking or get it turning over again. If I can get it crank reliably, it will likely start as I have a good spark on the plugs. If not, it likely will be something with the fuel system. The carb could be suspect due to sitting for so long.

Down the road the next issue I have to deal with are the brakes. The last time I drove it they barely worked. I may have to haul it to Phoenix and see if someone there can rebuild the brakes and replace assorted seals/gaskets for me. My tractor is generally in good and original shape so I'm determined to get it going again.

(quoted from post at 01:34:01 12/04/22)

Down the road the next issue I have to deal with are the brakes. The last time I drove it they barely worked. I may have to haul it to Phoenix and see if someone there can rebuild the brakes and replace assorted seals/gaskets for me. .

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I did not know 9Ns had brakes

TOH

It just seems that way because most of them don't work.
Perhaps Bugatti designed Ford brakes.
Bugatti was once asked why his cars had such an miserable brake system, he replied,
My cars are deigned to go. Not stop.

I had much the same problem with my '41 9n. I removed the starter switch and found the contacts corroded. I cleaned the contacts
and it works well. It is a bit tricky to split the switch,but not too hard to do.

(quoted from post at 15:49:21 12/04/22) It just seems that way because most of them don't work.
Perhaps Bugatti designed Ford brakes.
Bugatti was once asked why his cars had such an miserable brake system, he replied,
My cars are deigned to go. Not stop.

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When I got my N brakes didn't work well. They shoes had not been adjusted since?

I adjusted the shoes and things were good, until the axle seals started to leak........

(quoted from post at 11:34:01 12/04/22)
Thank you Den and Mad Farmer. All you fellows have given me some really good pointers to work with and I will follow through on all of them. Due to a long "honey-do" list to deal with before Christmas it likely will be a couple of weeks before I can get back to the Ranch where I have my tractor. To answer your questions, my 9N does have a negative ground system and I do have the Ford Manual to read, although you guys have been more helpful. I just purchased a Commercial grade 6 Volt battery from NAPA with 785 cranking amps and it did turn over the engine briefly but I could not keep it cranking or get it turning over again. If I can get it crank reliably, it will likely start as I have a good spark on the plugs. If not, it likely will be something with the fuel system. The carb could be suspect due to sitting for so long.

Down the road the next issue I have to deal with are the brakes. The last time I drove it they barely worked. I may have to haul it to Phoenix and see if someone there can rebuild the brakes and replace assorted seals/gaskets for me. My tractor is generally in good and original shape so I'm determined to get it going again.

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If you go the extra mile those brakes will lock the rear wheels, if you take poor advice and do a hack job you can join the "They don't have brakes club".

My brakes easily lock the rear wheels. If you do it right with sure seals you should never have to do again.

Whuts doing it right. Its always interesting to see how folks replace the original outer seals how did you get them out.