New Fan Belt?

mwbailey

Member
So, the old 8N, front mount distributor, 1949
model, will crank up and run well for a while,
then will crank but not start unless the
battery is recharged. I'm assuming alternator
issues -- 12V conversion before I bought it. I
get 12+ volts at the battery even when running.
Ammeter shows negative when lights are turned
on, about zero when off. Removed alternator --
one wire type -- to take to parts place for
checking. Figured I should replace cracked
belt. Do you REALLY have to remove the fan to
get the belt off? I did that, but figured
there had to be a better way. . . .

Let me know if I've messed things up!!
 
Mine will fish out of there without taking the fan off.
Just have to get it off the crank and past the bolster first.
You didn't likely mess anything up unless you hit the radiator.
 
my 2n and 8n belts always came off with the fan in place. was tight and you had to maneuver the belt around the blades and radiator.. but it worked.

check that battery too... a charged 12v bat should run an N for days..
 
mwbailey.......remember yer N-FAN belt is 5/8" wide. This is NON-standard fer alternators. CAUTION: too NARROW (1/2") belt will end up riding the BOTTOM of the groove and will NOT successfully run the water pump and fan blade. (fan belts transfer power thru sides of belt) Generally, yer fanbelt is so OLD, that you CUT it off. There are "emergency" fanbelts that are kinda like bicycles chains that you can use that doesn't take fishing the fanbelt thru the fan blades, just snap'em together. Simple, eh?........Dell
 
I found a guy selling wide alt. pulleys on Ebay last nite Fan & pully for $20. Look up "tractor alternator pully" ....
 
(quoted from post at 20:36:53 11/05/14) YT has alternator pulleys for cheaper than $20.00.

http://www.yesterdaystractors.com/Ford-2N_Pulley-Alternator-Wide_AFD5035.html

Well, I took the alternator in to Advance Auto to have it tested (there seems to be a slight conflict of interest, but what the heck?!). Results were 11.7V charging; not quite enough for a 12V battery. So, I now have a new alternator. The guy at Advance swapped pulleys for me, so no problem with the wider pulley. He had to order a new belt (old one was cracking and had stretched, we presumed, to over 45") -- should be a little shorter but 5/8" as Tractor Forum recommends.

Interestingly, the existing alternator did not have a fan. . . .

Now, I guess I'll find out if this alternator works with a one-wire set-up. The Advance guy matched the alternators as best he could could, but the instructions suggest other connections through "idiot light" and so forth. Hope to install it tomorrow when the belt comes in.
 
(quoted from post at 15:03:00 11/05/14)
Now, I guess I'll find out if this alternator works with a one-wire set-up. The Advance guy matched the alternators as best he could could, but the instructions suggest other connections through "idiot light" and so forth. Hope to install it tomorrow when the belt comes in.

I would guess that it's not a one-wire alternator UNLESS the instructions say it is. I don't know if any damage would result from trying it. I'd just go ahead and do the extra wiring as in the instructions.
 
Got the fan belt -- although it was 9:02 when it got there instead of 8:00 AM; had to take a swing by Office Depot to kill time. Got the new alternator installed, put the fan belt and fan back on, and when I started her up, she squealed like a stuck pig. Took the alternator back to Advance Auto; swapped it out. Installed on tractor and still got about 12.4V when she was running. Maybe I'll wait until the battery gets really low to see if it'll charge. . . . Even found alternator parts number on the Internet and two guys said it would work as one-wire; maybe, maybe not.

Did add a wire from light switch to the rear light that was installed on fender when I bought her. Didn't follow original route but did have two wire clips already installed on left side of tractor that I used. Zip ties around axle should hold everything in place.
 
The squealing may have indicated that it was trying to charge
and the belt was not tight enough to handle that much load.
Also, when running as a one wire, you may have to rev the
engine quite high to get it to start charging. Won't do it at idle.
Another option, if it has all three terminals, wire it as a three
wire. It's only one wire to the key switch, a diode and a jumper.
 
(quoted from post at 03:41:22 11/07/14) The squealing may have indicated that it was trying to charge
and the belt was not tight enough to handle that much load.
Also, when running as a one wire, you may have to rev the
engine quite high to get it to start charging. Won't do it at idle.
Another option, if it has all three terminals, wire it as a three
wire. It's only one wire to the key switch, a diode and a jumper.

Yep, [b:ba92d03cc2]Royse[/b:ba92d03cc2], I wondered about the belt squealing, but when I removed the alternator and spun the pulley, you could hear the squeal (of course, not as loud as when it was on the tractor). Advance Auto said the guy yesterday put the pulley on backwards -- had to change out for wider belt on 8N -- and that's what caused the squeal. I don't know about that, but it's not squealing now. Of course, it wasn't charging, either!?!?

I revved it up pretty good to get the alternator going, but that didn't seem to help. I have no problem with "one wire to the key switch" and probably not with "a jumper" if that's from one connection on the alternator to another, but "a diode" gets me in over my head. I guess I'm in for some research.
 
(quoted from post at 22:50:54 11/06/14)
(quoted from post at 03:41:22 11/07/14) The squealing may have indicated that it was trying to charge
and the belt was not tight enough to handle that much load.
Also, when running as a one wire, you may have to rev the
engine quite high to get it to start charging. Won't do it at idle.
Another option, if it has all three terminals, wire it as a three
wire. It's only one wire to the key switch, a diode and a jumper.

Yep, [b:7fed35ea56]Royse[/b:7fed35ea56], I wondered about the belt squealing, but when I removed the alternator and spun the pulley, you could hear the squeal (of course, not as loud as when it was on the tractor). Advance Auto said the guy yesterday put the pulley on backwards -- had to change out for wider belt on 8N -- and that's what caused the squeal. I don't know about that, but it's not squealing now. Of course, it wasn't charging, either!?!?

I revved it up pretty good to get the alternator going, but that didn't seem to help. I have no problem with "one wire to the key switch" and probably not with "a jumper" if that's from one connection on the alternator to another, but "a diode" gets me in over my head. I guess I'm in for some research.
The jumper is from the large stud on the alternator to terminal #2.
The wire from the key switch goes to terminal #1 through the diode.
You don't "have" to have the diode. A marker lamp from a car will work.
I use the diode because it fits inline with the wire and is easily covered in
heat shrink tubing to relieve the strain of vibration and keep it from shorting.
 
[b:0fb182b10b]Royse[/b:0fb182b10b], I took your advice. Wired for "three wire" and included an inline diode. Only thing left to do is tighten the fan belt a little; looked like it was slipping on a pulley somewhere and getting hot.

How's this for voltage?
mvphoto12822.jpg


Used an EAA (Experimental Aviation something-or-other) video on Internet to do a "special" soldering job to keep diode from being a weak link in the wire, maybe. . . .

mvphoto12824.jpg


Now, since the diodes came two to a pack from Radio Shack, I gotta find a place to store the second one until needed!?!?
 
Voltage looks good to me.
It will also start charging at idle, where a one wire may not.
Whatever you do with that diode, do not put it "right over
here where I'll know where it is". You'll never find it! LOL
Glad you got it up and running! :)

P.S. thanks for the follow up post. It helps us all to see what worked.
 
(quoted from post at 02:44:54 11/09/14) Voltage looks good to me.
It will also start charging at idle, where a one wire may not.
Whatever you do with that diode, do not put it "right over
here where I'll know where it is". You'll never find it! LOL
Glad you got it up and running! :)

P.S. thanks for the follow up post. It helps us all to see what worked.

Well, [b:8571e02ee0]Royse[/b:8571e02ee0], it just can't be that easy. . . can it? This second alternator quit rotating and the belt REALLY squealed and got hot. Took alternator off to find that the alternator fan was tight against front of casing and would NOT turn. Took alternator back to Advance; they suggested that pulley alignment may be off but were kind enough to swap the alternator again (including swapping out the wider pulley).

Got time to install the THIRD alternator today and didn't really see any out-of-alignment, but put a straight edge on it anyway. OK, so maybe the alternator pulley is a very little bit to the rear. Swapped the top bracket around since it looked just a little bit bent. Still looks like it's lined up pretty well. Started up OK, no squealing, charging at 14.4V. Sure hope this works.

Here are photos of alternator with three wire -- can even see where pulley threw melted fan belt (or maybe a little crankcase oil) onto hood -- and rear work light working. I have my fingers crossed.

mvphoto13181.jpg


mvphoto13182.jpg
 
Bailey,

It sure sounds to me like you are assuming that the three pulleys will line up perfectly every time you get a new alternator or pulley or flip the pulley. Correct me if I'm wrong.
 
Hello [b:dfe498b11d]Tall[/b:dfe498b11d],

"Assuming" might not be quite the right word -- "hoping" might have been more like it. However, it sure looked pretty straight the first time, and this last time I put a straight edge across the fan pulley and "imagined" that there was about 1/8" difference to the alternator pulley. Swapping the top bracket (the one with the slot for tensioning) that had a very slight (horizontal) bend in it seemed to move the alternator ever so much forward. Repeating the straight edge analysis suggested things were lined up.

I guess with all the comments about the 8N being easy to work on and pretty forgiving, I had "hoped" that 1/8" wouldn't make that much difference!! I'm still going to keep my eye on it. . . .
 

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