1940 9N cylinder not firing

Ron Vale

Member
I was plowing my fields last spring and kept having overheating and rough running problems.
I was checking plugs,wires etc. I had spark to all four cylinders. So I began running motor and pulling one wire at a time to see if the motor sounded any different. When I pulled 4,3 and 2 the motor changed drastically. When I pulled number one I had no change at all. So I figured I might have a valve problem. I don't know what the next move should be. I would appreciate any help I can get....(as for the overheating.. The radiator is original and I can see it has been repaired. I'm thinking I should change it out) Thanks Ron
 
Ron........umm, unlike when you pulled sparkies 4,3,2.......pullin' sparkie #1 had NO effect on engine runnin', why would you think you have a valve problem??? More'n likely you have a sparkie WIRE problem. Don't use modern "string" sparkie wire 'cuz itt'll BREAK inside the insulation and never sparkle yer sparkie. Use old fashioned COPPER core sparkie wire, cut to length. ($20, cheap) Yeah, I know that weird 4-nipple front mount dizzy is tuff to figger out. Yer original complaint of "ruff runnin" is typical BAD ignition points causing ruff runnin.

You do know the weird 4-nipple front mount dizzy is designed to be removed and points changed/adjusted on the kitchen table, don't you? Just un-snapple the capple and run to the kitchen. Change/adjust the points (0.015") Remember to "polish" the invisible CORROSION from between the points after installation. Me? I use a $1-bill clamped between the points and PULL. Iff'n yer really cheep, tear a strip from HEAVY brown paper grocery sack and use that. Installation is a reversal of the removal ...except... finger start the 2-bolts and install the rotor; now rotate the rotor until the OFF-SET tang falls into the OFF-SET camshaft slot. Now tighten the 2-bolts and re-snapple yer capple. Simple, eh?

This shuld fix yer ruff runnin' complaint .......Dell, yer self-appointed sparkie-meister
 
Could be what Dell says or you may have a simple bad spark plug. Take the #1 plug out and put it in #4 and see if the problem goes with the spark plug. If it is a valve problem a simple compression check should tell you if it is or not
 
Check your firing order 1-2-4-3 easy to cross up on F/M dist .# 1 hole is front of motor to rear of motor 1-2-3-4 moving aft. Do you have a thermostat? is it working . plenty of fluid in radiator. Hard water can plug one up 50/50 mixture anti freeze to distilled water.
 
Deffinately swap plugs and a spare wire if needed to see if the problem migrates. If not, then comp test that hole. Thumb and starter will give you a basic test to see if she is completely hung open or not.

Post back
 
thanks for replying....I figured I had a valve problem because I am getting spark to all four plugs. number 1 is just not firing.
 
Only use distilled water and antifreeze.
Don't have thermostat in right now. I put it in and take it out doesn't seem to make a difference....still over heats.
 
Is thermostat facing right way. Flat end to flathead. Do you know how to test a thermostat on the stove in a sauce pan of water.
 
Some times a plug will fire out in the air but not under compression so that is why you move the plug around and see if the problem goes with the plug
 
As others are telling you.....check the wire & plug. Just swap them around.

Regarding the t-stat, see tip # 25.

Regarding the overheating, see tip # 24.
75 Tips
 
overheating and dead cylinder,
This could be a long shot, but when the tractor is running look for air bubbles coming into the radiator.
A cracked head or bad gasket can pre heat your coolant. Also create a cylinder to not fire properly.
Have you had to any coolant to the radiator when running the tractor?
 

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