1700 Ford Ignition switch replacement for starter problems: Replaced the ignition

[rayikeo2]

Well, it looks like I finally found the problem to my intermittent starter problems on my 1700 tractor. The problem was in weather cold enough to need to activate the glow plugs. If I turned on the glow plugs before turning the starter, the starter would not do anything, no clicks no attempt to turn, nothing. Then as suggested on this forum I put a jumper on the solenoid. When I did that the starter would now turn over the engine. Note this was a new, 1 year old starter. Then the tractor would start. Now when it's 20 degrees outside and a foot of snow on the ground a non starting tracor can cause ulcers.

The fix: I bought a new ignition switch on ebay for $65 shipped and installed it yesterday. It works like a charm. However it isn't 20 degrees outside now so time will tell. Now the good part of interest. I took the old ignition switch and sawed it open to see the inside workings. There were some bad contacts and the 1 to the starter solenoid was the worst looking. I am going to take pictures of the insides of the switch. If any of you have a similar problem or are just interested as to what it look like inside the ign switch, I will post the pictures here for all to see. Let me know as I have not yet taken the pictures but can have them on here in 1 hour, if you are wanting to see them.

 

[rayikeo2]

Pictures of Ford 1700 ign switch inside contacts.

There are some contacts that were not giving full transfer of voltage.
#19 is to start aid and from start aid on down to #17 and then to glow plugs. Contact only worked part time because of bad contact.
#17 is from start aid to engine glow plugs.
#50 goes to starter solenoid through #50, but first through clutch safety switch and on to solenoid.
#AC goes to fuse box and dash lights (oil, charge and Temp ga).
There are 3 spacers which I marked as (guide). they have no function except to keep alignment of 3 metal power tabs when they are at rest (key off) they are sitting on these guides.

Other part has 3 copper connectors with a spring under each to push it out against the contacts. That part turns with the key. These 3 contacts are always powered through the center circle #30. Upper left copper contact in 1st picture with key hole (not shown) has a grove worn in it. This is the 1 that makes contact for the solenoid. This is where I lost good contact with the starter.

Functions: When key is off all contacts are at rest on guides.
Key turned to on: Power only to fuse box and dash lights (AC).
Key turned to start: Power to #50 solenoid and AC and #17 glow plugs. Release key returns to AC only
Key turned to Start aid: Power to AC and #19 and #17
Key releases from start aid: everything back to OFF at power rest.

 

[JC-jetro]

View attachment 327459View attachment 327460View attachment 327461View attachment 327462

Pictures of Ford 1700 ign switch inside contacts.

There are some contacts that were not giving full transfer of voltage.
#19 is to start aid and from start aid on down to #17 and then to glow plugs. Contact only worked part time because of bad contact.
#17 is from start aid to engine glow plugs.
#50 goes to starter solenoid through #50, but first through clutch safety switch and on to solenoid.
#AC goes to fuse box and dash lights (oil, charge and Temp ga).
There are 3 spacers which I marked as (guide). they have no function except to keep alignment of 3 metal power tabs when they are at rest (key off) they are sitting on these guides.

Other part has 3 copper connectors with a spring under each to push it out against the contacts. That part turns with the key. These 3 contacts are always powered through the center circle #30. Upper left copper contact in 1st picture with key hole (not shown) has a grove worn in it. This is the 1 that makes contact for the solenoid. This is where I lost good contact with the starter.

Functions: When key is off all contacts are at rest on guides.
Key turned to on: Power only to fuse box and dash lights (AC).
Key turned to start: Power to #50 solenoid and AC and #17 glow plugs. Release key returns to AC only
Key turned to Start aid: Power to AC and #19 and #17
Key releases from start aid: everything back to OFF at power rest.

Great work Ray. I sure will keep this thread for future reference. Good detective work:thumbsup:


JC,


ps. You know that I love to do postmortem autopsy just as you did here.

 

[rayikeo2]

Thanks JC. I thought the pictures might be interesting to some of the readers that are having starter problems. Ray

 

[woody]

I had to replace my neighbors switch on his 1700, use to he could wiggle to switch and it would start then finally it gave up and so did I. replaced it been working for a couple of years now.