Ford 8N having trouble starting -- many troubleshooting steps take -- suggestions?

[PorkChopsMmm]

I didn't work on the tractor last night because we are getting Noah's flood here but I saw on John's carb website and in other full carb rebuild kist online -- that there are gaskets that I don't think were in my carb. For example, they weren't there when I cracked the carb open so I never replaced them. The tractor was running without them for years it seems but it doesn't mean that it doesn't need them now.

For example, the little gasket around the float (from John's website M/S TSX Carb part 3]Page Not Found)


This gasket definitely isn't or wasn't in my carb. I think I should buy a kit similar to below and go through the carb. Even thought the carb isn't OEM -- do you think all the parts should line up?

Ford 2N 8N 9N Carb Carburetor Repair Kit TSX241A TSX241B TSX241C TSX33 1103 0050 | eBay


Although, this may not make a difference since the tractor still ran near identical with a different carb -- e.g. was still missing and stumbling even though the carb worked well on another tractor.

 

[Soundguy]

seats and parts like that with phenolic gaskets SHOULD have them.

most ms repop carbs rebuild with MS rebuild kits.

 

[sd455dan]

One more thing that I think needs clarified Is there +12volts at the coil during cranking(Not resistor reduced voltage) and Ford may have built it so that it gets only reduced voltage all the time (not sure ) but have seen some engine electrical setups that WERE that way ,it can cause hard starting, I would make sure the batteries full voltage is available at the + terminal when cranking, the fact that it has a push start and a key switch, makes me wonder if there is a push start (hot wire to the coil) or not- Also as Soundguy said if the push start is a factory one, the push button provides the GROuND to the factory ground triggered starter solenoid (but from your pictures it appears it is an aftermarket push button) the + voltage would have to come from the main hot +12 to the starter? if it does not have the full 12 volts at cranking to the coil + it will be harder to start... To test this theory right when ready to start connect a jumper from the battery + to the coil + and try it... if it does start, unhook the jumper and proceed from there..

 

[PorkChopsMmm]

It does/did have full voltage at the top of the coil and dropped while starting to a slightly lower voltage (which I believe it is supposed to).

 

[Soundguy]

again.. we have general comments that do not apply to this type of ignition system.

here we go again.

for all those that have obviously never worked on a ford front mount ignition.

here's the skinny.

ignition coil is a square job.. primary post on top... a primary spring on the bottom. this spring touches a concave screw INSIDE distribuitor as coil sets ATOP the distrib. this contact is common to the points moving section and the pigtail on the condensor. as dizzy shaft spins, the cam pushes the rubbing block opening and closing the points.. i'll eave out the basic kettering info as breaker contact points operation has been a 'science' since the turn of LAST century.

now.. the square coil also has a flat tap that touches a metalic post at the top of the distrib cap. this cap fits to the distrib and coil sets atop them both.

now.. back up. original setup.. there is a ballast resistor behind the dash. it's mounted to a insulator plate with 3 terminals. 2 top terminals have the resistor across them. bottom terminal is a hot wire. key switch is wired between that bottom terminal and one of the top terminals.. OTHER top terminal runs to the top primary post on the ignition coil.

oe 6v ford ignition coil is really only about a 3.5 volt coil due to the way it was built and the technology back then, including heat disipation and insulation. the ballast resistor has a positive temperate coeficient of resistance. thus as current flows thru the resistor.. it heats up, and it's resistance goes up. when cold it can be as low as .5 ohms or so.. and when warm.. can be 1.8 or so. this was fords method to give hotter sparks at startup. turn on the key, and the coil is getting more voltage that it normally needs.. coil resistance is fixed.. amps are increased.. max spark potential is available... running like this would thermaly damage the coil and points... the resistor rapidly heats up and reduces current down to a normal designed limit. later fords 65+ etc, used a bypass solenoid setup. power from key to coil is thru a resistor wire.. at startup, the solenoid sends full bat volts to the coil.. incedentally.. them 12v 65+ machines use a 6v coil... thus the resistor wire..

 

[8n Bruce]

Hi Guy's Been here from the beginning. Just like to say in my limited 8N experience(5Yrs), the only lack of power,running rough & hard starts that I have had were Ign. points closed,plug wires crossed & cylinder head gasket burnt between #2&3 cylinders ( less than 1/4 " of gskt. missing). The two affected cylinders appeared to be working when each cyl. was unplugged(turned off). I used compressed air in #2 cyl. on compression stroke& the air came out #3 plug hole. I noticed your #2&3 were down slightly(came up with wet test). The possibility is there . Any thoughts Soundguy? Pork Chop Admire your Patience & deturmination !!!!:thumbsup:

 

[Soundguy]

100+ psi seems awfully high for a blown head gasket.

if it was inthe 60-80 range.. maybee...

 

[sd455dan]

again.. we have general comments that do not apply to this type of ignition system.

here we go again.

for all those that have obviously never worked on a ford front mount ignition.

here's the skinny.

ignition coil is a square job.. primary post on top... a primary spring on the bottom. this spring touches a concave screw INSIDE distribuitor as coil sets ATOP the distrib. this contact is common to the points moving section and the pigtail on the condensor. as dizzy shaft spins, the cam pushes the rubbing block opening and closing the points.. i'll eave out the basic kettering info as breaker contact points operation has been a 'science' since the turn of LAST century.

now.. the square coil also has a flat tap that touches a metalic post at the top of the distrib cap. this cap fits to the distrib and coil sets atop them both.

now.. back up. original setup.. there is a ballast resistor behind the dash. it's mounted to a insulator plate with 3 terminals. 2 top terminals have the resistor across them. bottom terminal is a hot wire. key switch is wired between that bottom terminal and one of the top terminals.. OTHER top terminal runs to the top primary post on the ignition coil.

oe 6v ford ignition coil is really only about a 3.5 volt coil due to the way it was built and the technology back then, including heat disipation and insulation. the ballast resistor has a positive temperate coeficient of resistance. thus as current flows thru the resistor.. it heats up, and it's resistance goes up. when cold it can be as low as .5 ohms or so.. and when warm.. can be 1.8 or so. this was fords method to give hotter sparks at startup. turn on the key, and the coil is getting more voltage that it normally needs.. coil resistance is fixed.. amps are increased.. max spark potential is available... running like this would thermaly damage the coil and points... the resistor rapidly heats up and reduces current down to a normal designed limit. later fords 65+ etc, used a bypass solenoid setup. power from key to coil is thru a resistor wire.. at startup, the solenoid sends full bat volts to the coil.. incedentally.. them 12v 65+ machines use a 6v coil... thus the resistor wire..

Fine- Sorry Soundguy I should have worded that part about the jumper to the( distributor primary connection) (that was my mistake) (since my background is in electronics i tend to think of things in the context of nodal electrical connections ) -not the physical way they constructed the distributor) That is my fault and can see how that would be very confusing to someone looking at the 8n front mounted distributor- in some ways Ford was ahead of the times, it was 1973 when GM incorporated the coil into the HEI distributor- Ford had them in there in the 1940sHave been reading this post since the beginning it has a wire wound resistor that does allow almost full voltage for what 20 seconds?( wire gets hot/ resistance increases voltage drops to the run voltage...) I personally have had several wire wound (ballast) resistors fail over the years or become unreliable Un like condensors (2)( you would think something as simple as a coiled wire crimped at both ends could be problematic until current and heat are added..also look at the picture of the one behind his dash is that rust or corrosion on the wire wound connection- that was my point- some vehicles I have owned were hard starters with this same type of set up, I changed them to allow full voltage at cranking and the starting did improve...that's why I asked him to try the jumper, one time if it doesn't start - fine Also should admit my sisters 8n (that I did all the work on) always started just fine with factory wired front mount distributor even when cold and wet out side, all of it's no start poor start and run problems were fuel related ,tank a disaster the fuel shut off needed to be replaced tank cleaned , the carb I had to rebuild ... but hers was all original 6 volt.

 

[Soundguy]

Fine- it has a wire wound resistor that does allow almost full voltage for what 20 seconds?( wire gets hot/ resistance increases voltage drops to the run voltage...) that was my point- some vehicles I have owned were hard starters with this same type of set up, I changed them to allow full voltage at cranking and the starting did improve...that's why I asked him to try the jumper, one time if it doesn't start fine disregard
It still has a primary power wire external connection does it not, no mention of opening up the distributor in any way...

in my experience.. if you have a ford front mount that won't start with a proper cold ballast resistor inline.. and will start with it jumpered. it is so marginal that a crow landing on the hood is likely to cause a no start....

the oe system is engineered with plenty of tolerance to provide more than enough coil voltage to start, assuming there aren't 70 year old frayed coroded wires with rusty and loose connections. To describe a different type of bypass ignition merely clouds the situation.

it's already been covered, many times, asking the OP to jumper from bat hot to coil top to look for a bad key switch.. wires.. resistor.. etc... the data is right here in the thread........

 

[8n Bruce]

Sound guy,If he did more than 3 compression strokes per cyl. wouldn't that give a false high,with a small leak?:confused3: