8N is hard to start, but runs great

I put this in Tractor Talk by mistake.

My 2N runs great and starts very easy, seems like it is running before the second "verump". I did put electronic ignition in it, but it did the same with points when they were nice and clean.

My buddy has an 8N, older restoration and a trailer queen. He gets it out once a year and it is always a fight to get it started. So he asked me to put electronic ignition on it because he got tired of fighting the points. Both his 8N and my 2N are front mount distributors. Both are still 6V and other than the electronic ignition and plug wires, they are both all original design.

The 8N is still a real bugger to get started. Once started it runs great, smooth over the entire range of RPM, but hard to start. We pull started it and it fired right up and it will start with the battery / starter but takes a long time. The carb has been recently rebuilt and seems fine.

I wonder if the coil is weak? Any ideas why this thing is hard to start but runs great, great oil pressure.

Any Ideas why this thing is so stubborn to start?

We pull started it and it fired right up

It could easily have stuck rings from sitting so long.

You can increase compression sufficiently by pulling it to start for two reasons. First, it's cranking faster which creates more compression & secondly all of
the battery current is going to the ignition & not the starter.

A compression test is easy to do & will answer a number of questions about your problem.


Minimum acceptable pressure is 90 lbs w/ the lowest pressure reading w/in 75% of the highest reading. Run the engine to operating temp, turn it off, remove all
4 plugs, remove the breather hose & make sure the choke and throttle are both open. Crank it at least 5 compression strokes or until the gauge stops moving.
Write down the first compression reading (that is the valves seating) then write down the reading after 5 strokes or when it stops increasing. You should have
two numbers for each cylinder. Then, add a tablespoon of oil to each cylinder & repeat the process, but you only need the final reading for each cylinder. Write
down the results & post back for help figuring out what it all means.
75 Tips

I am assuming this is 6V. If so, what Bruce wrote about the starter and the coil is probably your best first place to look. In short, the starter pulls so much current that the coil is starved of electricity and does not give a hot enough spark to start.

You obviously have a good battery. You could try swapping batteries to see if that makes a difference. Considering how little use the tractor gets, it could be that simple. Good luck, Dave

Old gas.

Dean

99.98% of all non-running, non-starting, hard starting issues are due to mucked up wiring. First order is the battery, the 'heart' of any electrical system. Get tested
by a trusty shop ontgehor test machine. Must sustain a full charge under load, specific gravity. Get a good brand and keep a trickle charger on it when not in use like
the DELTRAN Battery Tender unit. The most misunderstood functions on old Fords are, #1, the 6V/POS GRN Electrical System; and #2, The Ford Front Mount Distributor. many
don't get it, can't figure out one or both systems they end up trying, at first 12V, and when same problems occur, think they need EI to fix all of their problems. EI
eliminates points -that's it. ...I did put electronic ignition in it, but it did the same with points when they were nice and clean..... Didn't that raise a red flag
with you? 'Nice and clean points' means nothing if the unit isn't tuned up and timed correctly then tested and mounted correctly on the engine. Was it? Was the unit
mounted off 180 deg? If so, you busted the cam base and rendered it junk. It'll never fire right ever again. How did you wire up your setup before and after EI? Get
the ESSENTIAL MANUALS, both the original and JMOR's WIRING PICTOGRAMS to see and understand each setup. ...I wonder if the coil is weak?... Well, you can keep on
guessing like your weekly lottery numbers, or, apply a logical, true root cause problem solving method. Replacing parts without testing first to determine if bad or
good is just plain stupid and a waste of time, money, and resources. There is nothing wrong with the OEM 6V/POS GRN system, nor a 12V/NEG GRN switch over job, or even
an EI unit; they all have their own Pro's and Con's. The problem initiates when the wiring gets all mucked up because it is done wrong. If carb passes the fuel flow
test, leave it alone, it isn't a fuel issue. All your signs point to mucked up wiring.


Tim Daley(MI)

Something else to check...........

A 6v Pertronix unit needs a minimum voltage only 0.8 volt below 6volts (no margin). A low battery, less than perfect connections/cables and you get no spark.
But, you can pull start it just fine.
75 Tips

(quoted from post at 07:18:46 07/28/21)
I wonder if the coil is weak?.....
Any Ideas why this thing is so stubborn to start?

Click to expand...

Yes, What Bruce said

(quoted from post at 07:38:16 07/29/21) Something else to check...........

A 6v Pertronix unit needs a minimum voltage only 0.8 volt below 6volts (no margin). A low battery, less than perfect connections/cables and you get no spark.
But, you can pull start it just fine

Click to expand...

Walston. ,What size are the battery cables? To start with make up a new set with 0 or even 00 (better) cables with copper ends and heavy battery ends soldiered on and heat shrunk .clean shinny connections on all connections and cable ends and posts on.A verified load tested good or new 6 volt battery.Next remove the starter bolts and put a 5/16 nut on one of them to hold the starter together.Then sand the starter pocket shinny with some 40 grit paper also the end frame drive end,both sides barrel ends and brush end plate. so the starter has a good ground through out.
This will make a world of difference in cranking speed and starter draw.This will allow faster cranking speed and more power to the coil for great starts.

Walston, Your friends 8N could have a worn out starter motor too. Have it tested before just going out a buying a new one.

Follow up:

Checked all wiring and connections. all are clean, same result.

New battery, no change.

Rebuilt the starter, helped a bit, but still quite hard to start.

Swapped out the front mount coil and that fixed it. Fires right up and runs like new.

Walston; thanks for the update.