No spark

[Roy Warren]

First post in over a year, but have been reading all the post and archives for about 3 weeks, but still no luck.

1950 8N, 6 volt, side mount. After restoration tractor ran for a month or so, but never good. Ran rough, bogged down when load applied. Finally died.

Tried all the remedies I've read here:

Dell's sparkie test. No spark.
6V+ at points with points open.
6V+ at both coil post.
about 5V at top of coil with points open, 3V closed.
Jumped key switch. Still nothing.
New Battery and cables, New Carb, Drained old gas and replaced. New plug wires, coil, condensor, points
Tried 3 sets of points, rotors and condensors. 2 dist. caps.
Took #1 plug out, found TDC with finger, Rotor lines up with #1 wire. No mark on my flywheel.
Tried rotor pointing just before TDC and just after. Neither worked.
Points set at .015 and Autolite 437s at .025.
No play in dist. shaft.

Cranks okay but will not start.

I don't know what else to try, other than replacing the dist, but I hate to just throw more parts and money at it without knowing.

I would appreciate any help.

Roy

 

[r geiger(oR)]

side mount distributor points should be set to 0.025" not 0.015"

 

[Roy Warren]

Thanks. That's the kind of info I'm looking for. Most of the post I've read here say .015, but also, most of the post seemed to be front mount.

Under Research & Info/Tune-Up Specs on this page it says ".015" for an 8N. confusing

Thanks again.

 

[old]

0.015 if for the front mount and 0.025 is for the side mount. After you set them right get them at a point that they are closed and open them by hand. You should see a spark and hear a snap sound if they are working as they should be. Be careful doing that or it will bite you by the way but that is an easy way to check if the points are working

 

[r geiger(oR)]

The early 8n's were front mount dist. and the later years had the side mount distributors.
Good Luck

 

[Anonymous-0]

Do your spark plug wires have copper wire inside of them or radio suppreession? Do you get fire out of the coil?

 

[Roy Warren]

Thanks old,

I tried the test you said, and it does spark when I open them manually.

I reset them to .025. In doing so, I have may have stumbled on the problem.

At .025" the points never close all the way.

Does that mean the cam is worn out, or should I try another set of points?

Roy

 

[Roy Warren]

I just checked for continuity between the points with them on the flat part of the cam (supposedly closed).

They definitely are not closed. I can push on the movable point arm and the continuity light comes on. Release pressure and it goes off.

I don't mind buying a new distributor if it will fix the problem. I started wearing out after 50 years or so also.

 

[Roy Warren]

They're copper core.

I checked the voltage on the center (coil) post inside the dist. cap, with the switch on, and got about 6.3volts.

It's been several days since I did this and from memory, I think the points were open when I checked it. Closed, they were about half that.

Thanks for the input.

Roy

 

[JohnC IND]

New Points I just installed in the barn find 8n sidemount had a slot in the opposite end with a mounting screw through it. (The previous ones did not)Loosen both screws and try resetting them, allowing the base to swivel on both screws, and it just might work. I had set mine at 0.015, however, based on info I found in my old FO-4 manual. 0.025? Okay guys, which is it really? The tractor seems to run and start fine now.

 

[Dell (WA)]

Roy.......the points on the 5-nipple sidemount gap = 0.025". Set with the rubbing block on the cam highpoint. The points MUST CLOSE between hi-points. Time for 'nutter' set of points. The distributor cam seldom wears. Remember to polish the invisible contaminates from yer new points after installation by pulling a dollarbill between the closed points. .......Dell, yer self-appointed sparkie-meister

 

[JMOR]

(quoted from post at 19:45:39 06/02/09) New Points I just installed in the barn find 8n sidemount had a slot in the opposite end with a mounting screw through it. (The previous ones did not)Loosen both screws and try resetting them, allowing the base to swivel on both screws, and it just might work. I had set mine at 0.015, however, based on info I found in my old FO-4 manual. 0.025? Okay guys, which is it really? The tractor seems to run and start fine now.

0.015" front, 4 nipple.
0.025" side, 5 nipple.
HOWSOMEVER, if making & breaking the circuit, it will run anywhere from 0.010 or less up to 0.050 or more, even though the dwell & timing will not necessarily be correct.

 

[Bruce (VA)]

A new distributor goes for about $225. A new set of high quality NAPA Bluestreak points goes for $18. I think I'd try a new set of points that I know to be of excellent quality before I'd drop $225 for a new distributor. You wouldn't be the first N owner to get a set of cheaply made points.

And, make sure you adjust the points at .025 w/ a clean feeler gauge. And run some cardstock or a new dollar bill through them.
50 Tips

 

[JMOR]

(quoted from post at 18:58:09 06/02/09) Thanks old,

I tried the test you said, and it does spark when I open them manually.

I reset them to .025. In doing so, I have may have stumbled on the problem.

At .025" the points never close all the way.

Does that mean the cam is worn out, or should I try another set of points?

Roy

easure the cam. Rarely found worn out, but has been reported on occasion. As Dunk, I believe, asked once upon a time, "how long do you think you would have to rub steel with a little piece of plastic to wear the steel away"?

Across flats = 0.0720
Across peaks =0.0778

 

[Dell (WA)]

ah? John.......the 5-nipple sidemount points gap = 0.025". The 4-nipple frontmount points gap = 0.015". can you count yer nipples??? ......respectfully, Dell

 

[Roy Warren]

Bruce,

Thanks for the info. I'll visit NAPA tomorrow.

I have a continuity checker that has an allegator clip on one end and a pointed probe on the other. When you have continuity the light comes on. I'm sure you're familiar with these.

I clipped it to the movable side of the points and pressed the pointed end into the stationary side and pressed the starter button.

The light didn't come on all the way around the cam. So I know the points arn't closing.

Thanks again. I keep thinking it's going to be something simple.

Roy

 

[JMOR]

(quoted from post at 20:49:00 06/02/09) Bruce,

Thanks for the info. I'll visit NAPA tomorrow.

I have a continuity checker that has an allegator clip on one end and a pointed probe on the other. When you have continuity the light comes on. I'm sure you're familiar with these.

I clipped it to the movable side of the points and pressed the pointed end into the stationary side and pressed the starter button.

The light didn't come on all the way around the cam. So I know the points arn't closing.

Thanks again. I keep thinking it's going to be something simple.

Roy

guess I ought to let someone else break the news, but you got that bass-ackwards. If the light never comes ON, that would be more indicative of points never open......or more likely the feed-thru in the distributor wall is shorted.

 

[Roy Warren]

You got your decimals in the wrong places but I understand what you mean.

Mine is .720 across the flats. (0 wear)
and .772 across the lobes. (.006" wear) Not much for 50 years.

These were taken with the dist in the tractor. Should be able to get a better reading with it on the bench, but this tells me not to spend $225 for a distributor yet.

Thanks,
Roy

 

[JMOR]

(quoted from post at 21:04:36 06/02/09) You got your decimals in the wrong places but I understand what you mean.

Mine is .720 across the flats. (0 wear)
and .772 across the lobes. (.006" wear) Not much for 50 years.

These were taken with the dist in the tractor. Should be able to get a better reading with it on the bench, but this tells me not to spend $225 for a distributor yet.

Thanks,
Roy

What's a factor of 10 among friends? :roll:

Did you get my point about the feed-thru? This is a relatively common problem, along with the little copper connecting strip being broken.

 

[Roy Warren]

JMOR.

Maybe I didn't explain it properly.

If you put both ends of the continuity checker together the light comes on. When you seperate them the light goes off.

I put one end on one side of the points (movable) and the other end on the other point (stationary)

When the points open there is no continuity, so no light.

If they close you have a connection between the two points, so the light comes on. This isn't happening.

Roy

 

[JMOR]

Roy, "maybe I didn't explain it properly", or maybe I (JMOR) didn't receive/understand/interpret your message properly. I was thinking "test light", where the circuit being probed supplies the power. Now, I'm thinking that your continuity tester is self-powered. So, maybe we are communicating. Might want to make sure points don't have the invisible oxide insulation over the contacts. (They touch, but still no continuity)

 

[trucker40]

You seem to think you arent getting any fire after trying several sets of points?Tractor never ran good and rotor lines up to number one wire on compression stroke.
OK,get number 1 up on compression again,check rotor,check mark on fly wheel.If you dont find a mark on the flywheel turn crank in the direction of rotation 1 full turn.Do you see the mark on the flywheel?If you do,look where the rotor is pointing.It should be half way around from where it was.After drawing a diagram of which wire goes where,change your number one to where the rotor is pointing now,then follow which way the rotor turns and wire according to the firing order.See what happens then.If no luck you may need to switch your wires back,but before you do,squirt a little gas in each cylinder and see if it fires then.
You see your crankshaft turns two full turns for your cam to rotate one time.You might accidentally be on the wrong stroke which is the exhaust stroke and if you are or somebody is messing with you and switched wires around you might think you are in time but may not be.That would mean you were timed 180 degrees out of time.Thats a common mistake when working on a motor with a distributor.
Lots of other things it could be too.This may be something to try.I have worked on something and would swear the points arent firing.Change them and still no start.Walk away and not do anything else,but come back and see some problem like a wire off somewhere and fire it right up.A lot of times the answer is right in front of you but you just dont know it.About every time I work on something I get it timed 180 out the first time.Its kind of second nature now to try it both ways without even checking much of anything else if it fails to fire right up.Maybe some alligator clips on a piece of wire to bypass everything and go direct to the coil and see if you have fire then.I used to go to auto auctions many years ago when everything had points.Lots of times that wire with alligator clips on each end could get something running that would quit on the side of the road,and might even have been the reason the car was being sold to start with..If you yanked on a wire working on it you could have pulled it apart inside and not know it.

 

[r geiger(oR)]

On a 50 side mount 8N you should have the timing marks on the flywheel. the early 8n did not but if you have the hole you should have the marks. You may not have been on the compression stroke when you found TDC like previous posted stated.

 

[jonallgrow]

I had a similar problem last month and it turned out to be a shorted ground wire from the distributor to the block, i cut this wire out and replace it as suggested by Dunk and I eventually got it going... although i had a whole world of issues at that time and these guys here ALL helped me through it.
it was a small wire from the screw that holds the points down in the distributor grounding it to the block.
i am nowhere nearly as knowledgable as most on this forum but i thought i'd throw it out there...
Good Luck..

 

[JohnC IND]

Dell, Thanks for the reply... Mine's a sidemount 5-nipple. My older IT FO4 book says 0.015 for the sidemount. Hence the confusion. I suspect it's been corrected in later issues.

 

[Anonymous-0]

if points are set properly and are in closed position you should be able to pull coil wire out at distb. cap. hold coil wire being careful not to touch bare end, hold about 1/4 in. away from coil bracket, take screw driver and open and close points, should have nice blue spark jumping from coil wire. if not check wire or coil.this normaly elimates distb. problems. also putting distb. in at 180 degrees off is pretty common also.

 

[Roy Warren]

r geiger & Trucker,

I have turned the flywheel all the way around using a screwdriver through the hole in the side, tooth by tooth. I can't find a TDC mark.

My S/N is 8N-350765. Don't know if this S/N had the mark or not.

I also tried cranking the engine and watching the rotor turn. Everytime it passed where the number one plug wire is, I felt an upshoot of air from the spark plug hole. I feel like I have the distributor in the correct position.

Going to try new NAPA points this afternoon.

Thanks,

Roy

 

[Anonymous-0]

forgot to add to reply tests need to be made with ign switch turned on. not trying to be smart. but some times when nothing works and we are frustraded like i get some times i miss the things that are the simplist. thanks

 

[r geiger(oR)]

It does sound like the points. Someone must have changed the flywheel at some point in time, Sounds like you were on the comprssion stroke alright. Back in the days when I smoked I would use a piece of celophane from the cig. pack to check to see if the points were closing. Didn't have a test light.
Good luck

 

[trucker40]

Well it sounds like distributor is in the right place.Now you can actually feel a rush of air out the spark plug hole on the exhaust stroke,its just not as strong as the compression stroke.A few weeks back there was a discussion about if a new timing gear was used it could be a tooth off.If you changed that gear might be something to think about there.I havent worked on these old Fords a lot so everybody else knows more about them than me.I just have worked on a lot of motors over the years,mostly diesels,and they dont have all the electrical problems gas motors do.I wouldnt know why you dont have a timing mark?Maybe flywheel was changed?I have had bad points right out of the box before.They can get some kind of coating on them where they wont work but usually the second set works,I would go to a different parts store or different brand of points from the same store though just in case they had more than one set of bad points.Just thought I would throw that out there as I have been frustrated by this stuff lots of times and know what its like.