641D Starter Relay

[TX641D]

This is a starter relay on my 641D tractor. The positive battery cable goes directly from the battery to the post on the back side of this relay. When the battery is connected, should there be power to the post on the relay with the red wire? When i trace that red wire, it goes to a terminal block under the dash and looks like another wire on that same termal post goes to the Ignition Key lock.

When i put a test light on the terminal with the red wire and white cap, i get no power. Is the relay bad?

I included a copy of the 641D wiring diagram for 12V systems.

thanks!

 

[john in la]

We can not say the relay is bad at this time because you have not got that far yet.

I could tell you how to trace down the problem at the source (it sounds like your key switch may be bad) BUT you said the other day you are only trying to get the tractor running to see if it is worth fixing.

With that in mind lets do some test.
REMEMBER THIS IS FOR TESTING ONLY

Get two small jumper wires.
Unhook both small wires from the relay.
Use one jumper wire to jump power from the large post where the battry hooks to one of the small post (either one)
With the one jumper wire installed you should have power at both small post.
If not the relay is bad. do nothing and post back
Now install the second jumper wire on the second small post.
Touch the end of this wire to a good ground. This should cause power to come out the other large post and go to the starter cranking the motor over.

Post back with your results.

BY THE WAY
It looks like yo have two battery cables hooked to the starter side of the relay.
One goes to the starter
Where does the second wire go????????

 

[TX641D]

Thanks.....perfect! I will try that later this evening.

BTW, there is a red battery cable that goes from the positive terminal of the battery to the post on the back side of the starter relay. The red cable you see in the front of that pictures goes from the relay to the starter. It is red, because i could not find a ready-made 2-guage black cable at my local autoparts store. So i got the terminating ends and some red 2-guage wire and made a new cable between the relay and starter. If it ends up running, i'll get a black one

Can't wait to try the test...thanks!

 

[Errin OH]

Unless it has funky setup your wiring diagram doesn't show I think you biggest problem is your main tractor power is on the starter side of the relay instead of the batt side. At least I assume that what the second wire on the starter side is. The terminal block is BAtt and Ign. The key switch basicly shorts the two post. If in doubt wither the key switch works, just short the two post on the terminal block.

As for the relay;

Post from batt should have a wire runing to the terminal block along with the main batt cable.

Post to the starter shouldn't have nothing but the starter cable.

One of the small posts should be the power coming from the key switch via the terminal block. Power only there when key is on.

Other small post should be from the start switch and is grounded when depressed.

 

[awhtx]

Maybe it"s the wire going to the relay for the intake heaters (glow plugs). If so, he will only be able to heat those heaters while the starter is cranking the engine over so he probably won"t get much voltage to them.

 

[john in la]

That's what I was thinking.
His explanation above does not really tell me either

 

[TX641D]

Ok, I'm stumped:

1. I put a new starter relay on the tractor.
2. Per the wiring diagram above, here is how i have it wired
- Red Battery cable from + on battery to large batt post on starter relay.
- Also connected to batt post on starter relay is yellow wire which leads to "B" terminal on the voltage regulator AND Black wire which leads to batt side of the manifold heater relay.
- the "I" post next to the larger batt post on the starter relay has a red wire which goes to the hot side of the terminal block which also shares the red wire from the ignition key.
- the "S" post (second smaller post) on the starter relay has the wire leading to the push button starter switch
- the larger starter post only has the cable leading from the starter relay to the post on the starter.

3. I did put the jumper between large batt post and "I" post and pressed the starter button but still had silence.

4. earlier, i disconnected the two wires from the key switch and checked them with a volt-meter for continuity and confirmed that the key switch was working properly.

I thought that with that first jumper in place on the starter relay, i should have been able to push the start button and get a positive result on my test light when touching it to the starter post on the relay? I got nothing.

The only thing i havent tried is a new wire from the small "S" terminal to ground on the frame, which i suppose would tell me if my starter button was bad?

With the key "on", should there be power to the "i" post on the starter relay? I get nothing from my test light, even with a brand new relay and tested that the key switch is good.

Thoughts? Thanks!

 

[Lumpy]

Just remember that a automotive relay (solenoid) normally doesn"t work on a tractor.

 

[TX641D]

I replaced it with ford pn 311006 from the parts manual.

 

[TX641D]

OK....making progress:

Wiring config seems to be correct. Key is functioning properly and when "on" i am getting power to the "i" post on the relay. When the key is off, there is no power to the "i" post.

The third relay post which goes to the push starter and is supposed to "ground" and cause the relay to kick power to the starter post....right? That is not working which indicates bad push button?

I followed the earlier advice and made a jumper wire from the 3rd post and touched it to the frame with the key "on". I had disconnected the cable from between the starter relay and the starter so that it wouldn't engage the starter. But when i touched that ground wire from the third post to the frame....shouldn't I have heard that relay "CLICK" and give me power to a test light on the larger starter post on the relay?? That didn't happen. Odds that i have two bad relays are slim.

What did I do wrong??

 

[TX641D]

One more follow up question:

I accidentally crossed my test light across the second and third post and it seemed to make the relay "CLICK". Is that the same as grounding it with the jumper wire to the frame or the push button starter?

The groung jumper wire is just a 14 guage wire bolted on 3rd post and touching the other end to the frame. Is that not enough ground to kick the relay or should that work?

thanks

 

[NWMO 901 SOS]

(quoted from post at 16:35:43 07/24/10)
Ok, I'm stumped:

1. I put a new starter relay on the tractor.
2. Per the wiring diagram above, here is how i have it wired
- Red Battery cable from + on battery to large batt post on starter relay.
- Also connected to batt post on starter relay is yellow wire which leads to "B" terminal on the voltage regulator AND Black wire which leads to batt side of the manifold heater relay.
- the "I" post next to the larger batt post on the starter relay has a red wire which goes to the hot side of the terminal block which also shares the red wire from the ignition key.
- the "S" post (second smaller post) on the starter relay has the wire leading to the push button starter switch
[color=red:6868b99a49]- the larger starter post only has the cable leading from the starter relay to the post on the starter.[/color:6868b99a49]

[color=blue:6868b99a49]3. I did put the jumper between large batt post and "I" post[/color:6868b99a49] and pressed the starter button but still had silence.

4. earlier, i disconnected the two wires from the key switch and checked them with a volt-meter for continuity and confirmed that the key switch was working properly.

I thought that with that first jumper in place on the starter relay, i should have been able to push the start button and get a positive result on my test light when touching it to the starter post on the relay? I got nothing.

The only thing i havent tried is a new wire from the small "S" terminal to ground on the frame, which i suppose would tell me if my starter button was bad?

With the key "on", should there be power to the "i" post on the starter relay? I get nothing from my test light, even with a brand new relay and tested that the key switch is good.

Thoughts? Thanks!

TX,

Remove all original small wires from the starter relay.

With the two highlighted directions above complete (and 12V seen at the relay Batt post and small post jumpered to), test for voltage on remaining small post. It should register 12V. If not, relay is incorrect or needs replaced, your part number 311006 checks for your tractor.

When you test the second small post and find 12V, do the following.

Block the tractor and place the transmission in nuetral. Would even be good to keep the diesel killed at this point.

Take a length of wire and find a [color=red:6868b99a49]good[/color:6868b99a49] ground. Possibly back a bolt out and tighten the wire between the bolt and frame as you screw it back in. Now, with the tractor in nuetral and the diesel killed, when you touch the small post (without the jumper) with your newly grounded wire, the relay should close and energize the starter. If the relay closes (clicks) and it still does not try to start, check for 12V at the starter post when grounding the relay.

If you are getting 12V to the starter, confirm [color=red:6868b99a49]good[/color:6868b99a49] ground through the starter. If the starter is not grounded adequately, it cannot energize, even when 12V get to the starter post.

I have simply tried to share what John in LA did in his post in a different way.

Chris

PS - Just curious, where did the second wire from the starter side of the relay connect?

Now,

 

[TX641D]

Thanks. I secured a ground wire underneath the same bolt to the frame that the negative battery cable is connected to. I touched the end to the thrid post on the terminal with the key on and got nothing. Re-confirmed that I have power to the main Batt terminal and the second "i" post.

Only action i got all night was when I accidentally jumped the 2nd and 3rd posts with my test light and it sounded like the relay clicked.

Where does that leave me?

 

[NWMO 901 SOS]

TX,

Remove all original small wires from the starter relay.

[size=18:1718b6668f][color=red:1718b6668f]With the two highlighted directions above complete (and 12V seen at the relay Batt post and small post jumpered to), test for voltage on remaining small post. It should register 12V. If not, relay is incorrect or needs replaced,[/color:1718b6668f][/size:1718b6668f] your part number 311006 checks for your tractor.

When you test the second small post and find 12V, do the following.

Block the tractor and place the transmission in nuetral. Would even be good to keep the diesel killed at this point.

Take a length of wire and find a good ground. Possibly back a bolt out and tighten the wire between the bolt and frame as you screw it back in. Now, with the tractor in nuetral and the diesel killed, when you touch the small post (without the jumper) with your newly grounded wire, the relay should close and energize the starter. If the relay closes (clicks) and it still does not try to start, check for 12V at the starter post when grounding the relay.

If you are getting 12V to the starter, confirm good ground through the starter. If the starter is not grounded adequately, it cannot energize, even when 12V get to the starter post.

I have simply tried to share what John in LA did in his post in a different way.

Chris

PS - Just curious, where did the second wire from the starter side of the relay connect?

TX,

It sounds like you were given the wrong relay, but unless you test it as has been requested, you won't know for sure. Do you have the small post jumpered as requested? If you have it jumpered, you have bypassed the ignition and there is no need to mess with the key as you indicate you did. If you don't have it jumpered, you may be seeing 12V with no load that drops to squat when you ground the relay. Hence, the jumper to confirm [color=red:1718b6668f]good[/color:1718b6668f] voltage.

Chris

 

[john in la]

<font color=red>Only action i got all night was when I accidentally jumped the 2nd and 3rd posts with my test light and it sounded like the relay clicked.

Where does that leave me? </font>

That leaves you with the wrong relay
You have power at I and when you jump I to S the relay clicks. You got the wrong relay.

Try this to test my assumption.
Remove all the wires from the relay. As you are looking at the relay hook the large wire from the battery to the large post on the right.
With a jumper wire touch S to the large post the battery is hooked to.
Does the relay click.
If so you got the wrong relay.

I really do not understand why you changed the relay in the first place; and I find it counter productive to try and explain how and why the system works because I usually over load the person with info and they really get lost. This is why I give you test to do and from the results I can figure out the problem.

But here goes.............
The battery; jumper from starter relay to glow plug relay; and the yellow wire that goes to B on the regulator gets hooked to the large post on the right.
The red wire from the switched side of the key or terminal block gets hooked to the small post on the right.
The wire to the starter button on the trans gets hooked to the small post on the left.
The starter gets hooked to the large post on the left.
WITH THE CORRECT RELAY...........
You turn the key on and it supplies power to the small post. Since both small post are hooked together internally this means power will come out the other small post and will run to the starter button on the trans.
So in other words you should be able to read 12 volts with a meter or test light at the starter button when the key is on.
If you can not back track to you find power and you have found the problem.
Once you get power all the way to the starter button; pushing the starter button down grounds the power causing it to flow. This flowing power creates a magnet in the relay causing it to click and connecting the battery to the starter. This makes the starter spin and the engine cranks over.

 

[TX641D]

John,

First off, THANKS so much for the detail and helping me trouble shoot this. I think i am now down to a bad push button. Here is a bit of background on the relay swap that you asked about.

1.) When i took the original relay off of the tractor, the "Batt" terminal on the right fell off in my hand. So, i had to get a new relay.

2.) I went to Ford Parts catalog and got the FPN 311006. I got the new relay from tractor supply and the numbers on the packaging matched. But when you said there should be internal continuity between "I" post and "S" post, a simple test with a volt meter proved you to be right that the new relay was in fact, incorrect.

3) I found a 3rd replacement relay from my 641D "parts" tractor in the barn (it was in a hidden box of parts). I hooked it up exactly as you described and the relay is functioning properly in concert with the key (power to both "i" and "s" posts when key is on). However, the relay only activates with a ground jumper wire from "S" post to ground. It does not work with the push button starter switch.

Is replacement of that push button starter difficult? Looks to be bolted through the cover plate over the transmission. There is a seal under that plate. What am i getting into when i remove that plate to replace the starter button?

Thanks again for everybody's help!

 

[john in la]

OK you got power to the starter button; so now you have a choice.
You can start tractor by touching the wire to ground till such time you figure out if the tractor is worth fixing (per your words from a few days ago)
OR you could check to see if the switch on your parts tractor is good and use it (check with a ohm meter for continuity between where the wire hooks and ground "ONLY" with button pushed down)
OR you could buy all new parts. You will need switch 8N11500; switch gasket 8N11529; and trans top cover gasket E6NN7223BA. Cost is about $25 to $50 total depending on where you get the parts.

The 4 speed cover is easy to remove. Make sure the trans is in neutral; take the bolts out and lift straight up. Watch for the shift fork spring and ball that is held in place by the top cover that they do not fall out. Replace starter button and top cover gasket and install top cover back on trans.

 

[TX641D]

This should close out the "Starter Relay" thread. After 200 or so repetitions on the current push button, it seems to be working properly is now and getting good ground.

So, I connected the starter relay to the starter, turned the key on and pressed the button...... starter turned the motor over, sounded great....relay stuck in "on" position, so to stop it from cranking over I had to pull off the battery cable. Minor detail....can get another relay soon.

Now, i am in a position to figure out how to bleed the system and get fuel to it. If I can get fuel in this tractor, I think its gonna start right up!!!!

Thanks for all the ignition help!