Backfires and no power

[soder33]

I just bought a 1952 8N, side mount distribtor that backfires at idle and at all RPM's and has no power. It has been converted to 12v with a one wire alternator.

I did a search here, so I wouldn't waste your time answering a question that was already answered.

So, here's what I have done, with no change in how it runs. I replaced the spark plugs, cleaned the fuel line and bowl. Replaced the screen in the sediment bowl. Blew air back through the line into the tank. Removed the carb and cleaned out using carb cleaner, wires and compressed air. I replaced the rotor and distributor cap, filed the points, and made sure the firing order was correct. I even replaced the exhaust pipe and muffler.

Where do I go next. Is it a distributor problem, a wiring problem with the 12 volt conversion, a fuel problem or could a valve be hanging up? The guy I bought it from was not very knowledgable about it or he played dumb. He said it was rebuilt 2 years ago and that it ran fine until this spring. I can tell it was apart as the gaskets are newer, so I don't doubt it was apart at some point.

I am in need of expert help. I grew up using an 8N and it was the most reliable tractor we had, so I know there is an answer, I just can't figure it out on my own.

Thanks. Larry

 

[profire31]

I'm still learning more about these old N"s everyday but what I found when I had a problem that sounds like yours was the points. I didn"t file but replaced and the problem went by the time I hit the starter button. BTW the points I had to replace only had about 20 hours on them. If you decide to replace stay away from the tractor supply stuff as this is what I had a few problems with. Since I switched to part # FD6769X from NAPA the points issues have gone away. This part # may or may not work for you as I was dealing with a 6V front mount. Just a reminder this is what worked for me but you asked the question in a good place and there are many experts that can offer more info. Another good thing is to find a post from BRUCE VA and fine his 50 tips he put together. That info can get you through all the minor stuff with no problem. Good luck and hope you get the old girl going soon.

 

[souNdguy]

double check your fire order 1-2-4-3 then check spark quality.

post back.

soundguy

 

[Bruce (VA)]

First, re-check the firing order as Soundguy suggested. It is very easy to cross 3 & 4.

" filed the points"

Why?

When I was 16 years old making $1.25 an hour & a set of points cost $1, I filed points. I must have been good at it because I recall it was almost a weekly exercise. If you ever file a set of points, you will remove the metallic coating on them & reduce the life span considerably. Unless you plan to keep on filing them, plan on replacing them pretty soon!

Quality parts are critical to longevity. Having learned the hard way, I most always use Blue Streak brand points. They are made by Standard parts & available at many auto parts stores. (frontmount points also fit a 48 Ford as I recall) Beware of sticker shock: $16-18 a set. My next choices are CNH, Wells or Echlin. Look for a brown rubbing block. Unfortunately, many folks have experienced problems w/ points made by Tisco, Sparex, A&I Products and any TSC ignition parts.

Correct points installation & gap is also important. Make sure the blade is at a perfect right angle to the points & you want to feel just the slightest bit of drag when you pull the blade through the points. Make sure the blade is clean & that you dress the new points by running some card stock or a piece of brown paper bag through them. Gap is 025 on the sidemount on all four lobes of the cam. Make sure the points align correctly. Did you check the gap?

Even as tight as I am, I always change the condenser when I change the points…….and then I toss the condenser in the “used” parts box. A bad condenser is rare; you can tell if the points are pitted/burned w/ metal transfer.

Good hold-down screws are important. (tip # 37) If the heads are wallowed out, what do you think the threads look like? You can use machine screws as temporary replacements, but you should use the OEM Fillister head screws. The larger head is there for a reason. If you do use standard machine screws, make sure they aren’t too long & interfere w/ the advance weights. Always use star washers under the screws.

Timing is important to engine performance. Make sure you set the point gap before you set the timing. Timing a sidemount is pretty straight forward; it has marks on the flywheel. Did you set the timing?

Do you have voltage across the points when they are open? Verify the gap on the points at .025. Then, run a new clean dollar bill through them. New points sometimes have a residue & old points can corrode, or get grease from the distributor cam on them. Or, you could have used a dirty feeler gauge. (I always spray mine off w/ contact cleaner.) Make sure you have voltage across the points, as in past the insulator on the side of the distributor. That is a very common failure point on sidemounts & often hard to find because it is usually an intermittent short. If you find the short there, the Master Parts catalog lists everything you need on page 154. You can make the strip and you could also make the insulators as well. But, somethings are just easier & in the long run cheaper to buy. Get the strip, 12209, screw 350032-S, 12233 bushing & 12234 insulator & just replace it all.

Finally, what does the inside of the distributor cap look like? See any carbon tracks or brass shavings?

Post back w/ results; I'll be interested in what the problem was.
50 Tips

 

[Jerry/MT]

Check the firing order, the initial timing, and the centrifugal advance for function.

 

[JMOR]

(quoted from post at 09:29:20 08/18/10) I just bought a 1952 8N, side mount distribtor that backfires at idle and at all RPM's and has no power. It has been converted to 12v with a one wire alternator.

I did a search here, so I wouldn't waste your time answering a question that was already answered.

So, here's what I have done, with no change in how it runs. I replaced the spark plugs, cleaned the fuel line and bowl. Replaced the screen in the sediment bowl. Blew air back through the line into the tank. Removed the carb and cleaned out using carb cleaner, wires and compressed air. I replaced the rotor and distributor cap, filed the points, and made sure the firing order was correct. I even replaced the exhaust pipe and muffler.

Where do I go next. Is it a distributor problem, a wiring problem with the 12 volt conversion, a fuel problem or could a valve be hanging up? The guy I bought it from was not very knowledgable about it or he played dumb. He said it was rebuilt 2 years ago and that it ran fine until this spring. I can tell it was apart as the gaskets are newer, so I don't doubt it was apart at some point.

I am in need of expert help. I grew up using an 8N and it was the most reliable tractor we had, so I know there is an answer, I just can't figure it out on my own.

Thanks. Larry

ompression check.

 

[Anonymous-0]

change the coil, its probably very old and the oil is breaking down causing the coil to overheat