1949 8N hard starting

[Wasgd4u]

Tractor is hard to start, once it"s running for maybe a minute it stalls??
 

[souNdguy]

standard diagnostics first.. always.

check spark.. becuase it's easy.. then check fuel flow.

( i'm betting on a fuel issue there.. )
 

[L.B,]

Not much to go on. How much choke does it take to start it? Get it running and before it dies give it a little choke and see what happens,also will it throttle up or does it die if you give it gas? At this point sounds like a fuel flow problem. Post back on what happens with choking it.
 

[old]

The more info you can give the more we can in turn give back. Cost is the same but sure can save time for all of us.
6 or 12 volts??? What have or haven't you do to it and did this just start out of the clear blue or after you did something??
Check your spark at all 4 plug wires. It needs to be a blue/white in color and jump a 12 inch gap or more. Nexy pull the carb drain plug and make sure you have a good steady flow of gas for a few minutes. Catch the gas so as to lok for water or dirt etc. Thne post back what you find
 

[Bob Purinton]

"...and jump a 12 inch gap or more."

Some of us might know he meant a 1/4 inch gap. I"m correcting him for the new guys.
 

[L.B,]

Hey old a 12 in spark, its a N not the electric chair!LOL
 

[old]

Typo should read a 1/4 inch gap but I bet your knew that right???
 

[old]

Spark gap should read 1/4 inch not 12 inch gap.
 

[old]

Years ago I worked on an insulation tester for the power company who owns Bagnell dam here at the lake of the Ozarks. That machine would do that 12 inch gap and then some shoot it would do a 3 foot arc. But yes should have read 1/4 inch gap
 

[Wasgd4u]

6 volt,spark is good,plugs are newer,fuel flows from carb clean.Havn't monkeyed with anything recently.
 

[Bruce (VA)]

" 6 volt,spark is good,plugs are newer,fuel flows from carb clean"

Well, if you are saying it has good fuel & spark, then the tractor is running & you are just hard of hearing......or maybe you missed something in your diagnostics! :)

Start over.

It takes three things for an engine to run: spark at the right time, compression, & fuel in the right mixture. For the moment, forget about compression & concentrate on narrowing the problem down to spark or fuel.



There are three very important tools you always need to have in your N tool box: a 3 inch piece of wire w/ alligator clips on each end, an old spark plug w/ the gap opened to at least 3/16” ( ¼” is better) and a 7/16 box end wrench. (see tip # 50 at the link below) And, you really do need a working ammeter on the tractor; it is a very important diagnostic tool. With these tools, you can quickly narrow down most N problems to spark or fuel.



Next time it stops, check quickly for fuel then spark. When I say quickly, I mean get off the seat, grab the tools & do it right then. Do not wait a minute or two. First, check for fuel. Get a can & put it under the carb. Remove the bolt in the bottom of the carb; as long as the fuel is turned on, you should see gas flowing out of the carb. Let it run for at least 30 seconds. If it’s a dribble, or runs for 5 seconds & stops, or none at all, you have solved half the problem: it’s fuel related. If gas flows well out of the carb & only stops when you turn it off at the sediment bowl, chances are very good it’s not a fuel problem. So, next, turn the key on, crank the engine & look at the ammeter. What is the needle doing? Does it show a constant discharge, no movement at all, or does it move back & forth slightly? Next, get the old plug, ground it to a rust & paint free spot on the engine, turn the key on & crank the engine. If the spark jumps the 3/16” gap, you probably don’t have a spark problem. If it won’t jump the 3/16” gap, you have a spark problem. If the ammeter needle shows a constant discharge, or doesn’t move at all, that also tells you that you have a spark problem. Jump the ignition switch w/ your jumper wire & see what happens. If it runs, you found the problem. If it doesn’t have spark after you jump the ignition switch, post back for more info on further troubleshooting. (and do not forget to turn the ignition switch off; see tip # 38)



If it does not have gas coming out of the carb at a steady stream w/ the bolt out for at least 30 seconds, you have a fuel problem. First, remove the gas cap. Your vent could be clogged & it vacuum locked. If that doesn’t work, tap the carb bowl w/ a hammer handle in case the float is sticking closed. (don’t whack it w/ the head of the hammer; you can crack the bowl). If you still don’t see gas flowing, the N has three fuel screens; one in the brass elbow, one in the top of the sediment bowl & one on the stem of the sediment bowl in the gas tank. Check the screen in the elbow & the screen in the top of the sediment bowl. (don’t worry about the one in the tank) Both probably need to be cleaned. If you have the fuel knob turned on all the way, & 1 gallon or less in the tank, it may be trying to feed off of the reserve inlet which is probably clogged. Only open it 2 full turns. Put at least 2 gallons in the tank. (and do not forget to turn the gas off; see tip # 9)



There are ways to check for spark & fuel that work & ways that don't. For example, having gas to the carb is nice, but having it past the float is what counts! That’s why removing the 7/16” bolt in the bottom of the carb is the way to check for fuel. And, same thing w/ spark at the plugs. Some folks think that checking for spark means pulling a plug wire off & looking for one. Well, it's the distance the spark jumps at the plug that gives you the info you want. It takes about 17kv to jump a 3/16" gap & 22kv to jump ¼” in the open air. Remember, it’s 14psi outside of the engine & about 90psi at a 6:1 compression ratio in the cylinders & compressed air creates electrical resistance, so you really need the 17-22kv to fire the plugs when the engine is running. A store bought plug checker will work better than an old plug because it won’t shock the snot out of you like an old plug might!
75 Tips

 

[Dell (WA)]

wasgd4u........there are 4-common runtime issues with the weird 4-nipple frontmount dizzy.

1) runs fer about 5-mins, and quits; restarts inna'bout 5-mins, CLOGGED in the tank filter; NOT yer problem
2) runs fer about 15-mins and quits; restarts innn'bout 15-mins; BAD weaksister ignition switch; NOT yer problem
3) runs fer about 1-hr and quits; restarts after about 4-hrs. BAD squarecan ignition coil. NOT yer problem
4) runs fer about 1-min and quits; restarts inna'bout 5-mins; BAD condenser. Sound like yer problem??? Condensers can be BAD right outta the box. Condensers keep yer points from burning. BAD points mean weak sparkies and hard starting. .........HTH, Dell yer self-appointed sparkie-meister
 

[souNdguy]

ditto what bruce said.

also.. fuel running thru the bottom of the carb is good.. but if it's mainjet is plugged.. she won't run.

can you get her running easilly and keep her running on start fluid puffed into the carb mouth ?

if so.. double check fuel.
 

[L.B,]

Ya
 

[Wasgd4u]

Me floats was stuck,tapped on the bowl a few times and she started right up,thank you gentlemen!