Another 8N Not Starting Question

[Rockfootball47]

I have been browsing your forums for the past few months while I have been working on rebuilding/tuning up a 1947 Ford 8N and found a lot of useful information, and am finally at a point where I need your help.

That past few months my friend and I have replaced the radiator, radiator hoses, fan belt, spark plugs, carburator, muffler, oil pressure gauge, wiring harness, battery, starter solenoid, all engine gaskets, sediment bowl, fuel line, ignition, motor oil, oil filter, transmission fluid and tuned up the distributor. Note that this is still a standard 6V tractor with a generator. This weekend we were finally at a point when we were ready to start it, and of course nothing happened. Confirming there was voltage to the Starter Solenoid we decided to try a jumping method across the starter solenoid that I read about online, and was told to do by the shop owner where we had been buying some of the tractor parts. This allowed the starter/engine to turn for a good 30 seconds with no starting until we noticed water leaking from the gap between the head and the engine block, so of course we stopped. After some investigation we realized that I didn't tighten the header nuts to spec (60-70ft lbs I believe). This allowed the water in the cooling system to leak everywhere. About 1 gallon of the 3 leaked out. It got in the carburetor and cylinders. Trust me I am still kicking myself for this stupid mistake. Never again will I not check a torque spec when working on a engine. :thumbsup: After talking to my friends dad we removed the header and removed all of the water from the cylinders and cleaned them with carb cleaner to ensure dryness.

We reassembled everything and tried again, but it still wouldn't start. We referred to the ye ole' Fuel/Air/Spark formula and discovered that we had fuel and air, but there was no spark. We checked all spark plugs by grounding them against the block to which none of them sparked. We basically already assume something is wrong with our wiring or the starter button since we had to "jump" it across the starter solenoid. Come to think of it that also explains why we found another push button on the instrument panel that we couldn't account for during teardown. But it was rotted away on the connector side and it didn't show up in our diagrams so we didn't worry about it.

We have no idea where to go from here. My only assumption is the distributor since we aren't getting spark. Since we did a complete tuneup of it before this happened we can't be sure, but don't know how to check.

Any help is appreciated!

 

[Soundguy]

are you aware that the 8n uses a 3 terminal starter solenoid, and that the small terminal faces the block. and when you ground that small terminal using the tmhumb safety switch on the trans.. that is when the solenoid activates. to test this to can put trans in neutral and blck clutch and ground that small 3rd terminal. if nothing,a nd it is hooked to battery.. for kicks.. reverse the big connections and try again in case it was made backwards. if nothing.. instead hit that small terminal with bat power .. if it makes it crank. WRONG solenoid. it's a car/truck solenoid.. not a tractor solenoid.

now.

when you turn key on.. basically what you have is the key between the lower terminal on the ballast resistor and one of the top terminals. the other top terminal is what runs tot he coil.

us e atest lamp or vom and see , when key on, if you have power at the key, and at the coil top.

next.

points gap is .015

if you hav epower at the coil but no sparks. put test lamp inline with coil and crank over. lamp should blink. lamp stays on and poitns or condensor or breaker plate is shorted.

no lamp and points are not closing.. or contacts are dirty.

post back.

 

[Rockfootball47]

are you aware that the 8n uses a 3 terminal starter solenoid, and that the small terminal faces the block. and when you ground that small terminal using the tmhumb safety switch on the trans.. that is when the solenoid activates. to test this to can put trans in neutral and blck clutch and ground that small 3rd terminal. if nothing,a nd it is hooked to battery.. for kicks.. reverse the big connections and try again in case it was made backwards. if nothing.. instead hit that small terminal with bat power .. if it makes it crank. WRONG solenoid. it's a car/truck solenoid.. not a tractor solenoid.

now.

when you turn key on.. basically what you have is the key between the lower terminal on the ballast resistor and one of the top terminals. the other top terminal is what runs tot he coil.

us e atest lamp or vom and see , when key on, if you have power at the key, and at the coil top.

next.

points gap is .015

if you hav epower at the coil but no sparks. put test lamp inline with coil and crank over. lamp should blink. lamp stays on and poitns or condensor or breaker plate is shorted.

no lamp and points are not closing.. or contacts are dirty.

post back.

Thanks for your help Soundguy!

I am familiar with the 3 point solenoid. The original on the tractor had the small terminal coming out of the S instead of the I & was rusted so I bought a replacement. This one to be exact which had the small terminal coming out of the I. I caught this before installing but figured it was just an upgrade, and that if didn't work I could switch it back to the old one which might still work. I did actually try switching back to the old solenoid to no avail.

I am not familiar with the tmhumb safety switch on the trans. Is it located on the transmission?

Would any standard test lamp work? What is a vom?

Thanks again for your help. I really appreciate it!

 

[murphy1244]

vom- volt ohm meter.

 

[Rockfootball47]

vom- volt ohm meter.

Oh I have only ever heard them called Multimeters.

 

[Soundguy]

the 8n uses a neutral interlock safety push button start switch on the top of the tranny.

it is merely a grounding switch. a wire runs from there tot he small terminal on the oem solenoid on an 8n. thus you can test the solenoid by grounding the small terminal. solenoid must be mounted in correct orientation otherwise field will not be powered. field is between battery wire and small terminal.. thus mouning direction is not interchangeable.

 

[Rockfootball47]

the 8n uses a neutral interlock safety push button start switch on the top of the tranny.

it is merely a grounding switch. a wire runs from there tot he small terminal on the oem solenoid on an 8n. thus you can test the solenoid by grounding the small terminal. solenoid must be mounted in correct orientation otherwise field will not be powered. field is between battery wire and small terminal.. thus mouning direction is not interchangeable.

Thanks again for your help Soundguy. I am planning on taking another shot on the N next weekend with a friend and his dad who has experience with engines. I plan to try all of your tips. I will let you know the results!

 

[Soundguy]

remember.. you can always pull the solenoid and use a gator clip wire from small terminal to ground, and then hit one large terminal with hot. if nada. hit the other large terminal with hot. ONE of them should make it engage. if neither do.. it's not the correct solenoid. if it does work.. simply hook it up witht he hot post that made it clunk hooked to the battery, other post to the starter. then small post to the interlocked switch.. which just connects to ground when pressed and in neutral.. etc..

 

[94BULLITT]

Is the ammeter bouncing when you crank the tractor?

 

[Rockfootball47]

Is the ammeter bouncing when you crank the tractor?

I wish I could state this for a fact, but I don't recall it even moving. I could be wrong though. A lot was going on in the heat of the moment.:mur: And I replaced it before trying to start it.