8N Wont run.. out of ideas

jwest

New User
So a year ago I got this 8N out of storage and got it running with the help of you all on here. It turned out to be timing related back then and simply adjusting
it slightly seemed to get it going. So all year long I put it to work but to get it running I would adjust the timing a few degrees by turning the distributor
counter clockwise and when it started I would turn it back to get it running smooth. Now, after sitting for the winter its time to put it to work again and it
wont start.

It's a late model, 6V pos ground, with a side distributor. It's got an a recently replaced (strong) battery, new points, condenser, distributor cap, distributor
rotor, plugs, and wires. Points and plugs are gapped properly at 0.025 inch and I get a good blue spark on all plugs. Compression tests between 100 and 110 psi on
all cylinders. I get a constant stream from the bowl with the fuel on and the carb is clean and gaskets in good condition. Its timed 4 deg before TDC with some
adjustments made here and there as described above.

Now the problem is it's really hard to start; usually before it fires off I get a few fires here and there but nothing enough to disengage the starter. When it
finally goes and the starter disengages, I get only a few revs (maybe runs 2 seconds) before it dies. About the only thing I haven't done now is replace all the
wiring, which is my next step. Any other thoughts or ideas?
 

Just a wag, but is the bendix kicking out too soon? You seem to have the three things that you need to make it run. can you pull start it? might tell you something one way or the other.
 
Jwest,If you are having problems with the starter disengaging when trying to start it.You might want to replace the starter drive wit a new improved clutch style drive that will stay engaged when starting your engine.
wm_52-11350C.jpg

Starter Drive
 
What I would have done first
if I had been in your shoes
Was bring #1 to perfect TDC
and static time it at the points.

It never fails and like my truck outside
should start and run perfectly
even before I get around to shining a timing light on my flywheel ball
which you could do too after static timing.

My GM engine has a nice TDC flywheel mark on it as well as the timing mark.

The trick is to catch the piston precisely when it hits the top
of its stroke, not a hair later,
and not in that free space between arriving at TDC
then heading down. :)

If you want me to tell you how I bring the piston up and watch it's progress the whole way, just ask me.

It takes a few tries to land in the sweet spot of static timing.

If that fails to get her to run right, then because good static timing is your best first shot, then look elsewhere for the trouble. but no matter what trouble you find, you will still be better off for having re-timed it.
 
Thanks for the suggestion, but the starter only disengages as the engine begins to start as it should. The problem is the engine won't stay running.
 
The oil is a bit dirty but nothing too bad. I've also tried starting it bypassing the filter and have the same result.
 
It doesn't seem to be a problem with the starter/bendix. It seems to kick off the starter at the appropriate time when the engine sounds like it should take off.
But it only runs for a second or two then dies.
 
I have it timed to 4 deg before TDC per the manual. I have no markings on my flywheel other than a TDC marking though, the rest are rusted over, so it's more of an
estimation. Though I've tried adjusting it both directions with no luck. You're suggesting I time it to have the points open on the #1 compression stroke at TDC?
 

No . . .
not with the points "open" per se.

if your distributor runs [b:b0b6f0bb56]counter clockwise[/b:b0b6f0bb56]

With #1 at TDC sweet spot
rotate the dist [b:b0b6f0bb56]counter clockwise[/b:b0b6f0bb56] until the cam follower/rubbing block of the rotor is just to the left of a cam shoulder and the properly set points are closed.

Turn the key on

Rotate the dist CLOCKWISE, slowly and carefully until the points barely BEGIN to open and throw a spark Tighten it down.
 
How old is the gas in the tank?

Tell us your start up procedure. Updraft engines are a might persnickety when it comes to lighting them off. I'm guessing engine is OK just need to tweak the start up.
 
I bought a jubilee while back. original 6volt. it was hard to start. now I am terrible on overhauling carbs so I bought a new one on ebay for 59 bucks shipped. Installed it and she works great. You may be getting fuel okay out of your sediment bowl but that doesnt mean you carb is okay. To me it sounds like you should replace your carb. you see a lot of prices out there but the prices has came down. with the loss of people fixing these old 8n tractors up I suspect there a lot of carbs sitting on the shelves. anyway just my thought. good luck. norm
 
Great suggestions here, but have you tried starting fluid? Not only into the carb, but also spray it around the manifold mounting area.
 
I had no idea carbs came down so much. Not sure if it will fix my problem, but I went ahead and ordered one just to have a spare for $44 shipped. Thanks for the heads up!
 
Gas is only a month or two old. My previous start up procedure was: Open fuel valve 2 full turns, turn distributor a few degrees CCW, ignition on, throttle to 1/4,
pull choke all the way out, hit starter, after 2-3 revolutions reduce choke to half. After starting, turn distributor CW until engine runs smooth.

The distributor thing was always odd to me. Never could figure out why it needed that to start. But that method no longer works and it will fire for a few
revolutions now but won't run.
 
This is how I timed the engine. I even used a multimeter to tell me when the points were just opening, instead of relying on sight.
 

retarding the spark will always help starting and that is what you were doing.
I would still try to pull start it myself.
My first 8n would act the same way as your until I changed the starter bendix. haven't had that problem since.
 
My previous start up procedure was: Open fuel valve 2 full turns, turn distributor a few degrees CCW, ignition on, throttle to 1/4, pull choke all the way out, hit starter, after 2-3 revolutions reduce choke to half. After starting, turn distributor CW until engine runs smooth.

Set timing to specs, tighten the distributor and try this; throttle about half way, no choke until it has turned over several revolutions. Updraft carbs need air flow for the choke to work - Choking first doesn't allow air flow. Hold the choke closed for just a few revolutions or you will flood it. When it starts, release the choke. If it stumbles, snatch the choke until it catches and then release. Repeat until it runs without choke.

It shouldn't be a problem if all of the gas in the tank is only a month old.

What is the air temperature where you are - Is it cold still?
 
Got it running finally. Turned out to be the wiring harness. After checking for good spark for the 3rd time, I thought I'd check to ensure it sparked many times in a row and I noticed that it would miss a revolution every now and then. I bypassed the harness and it started right up. I've got a new harness on order. Thanks all for the suggestions.
 

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