Ford 850 starting procedure cold and hot

My Ford 850 has a 6v system. I was having trouble getting it to start cold or hot and with it running rough when hot. I put a new ignition switch on it less than year ago.

I noticed that the spark at the points was occurring only intermittently so I replaced the points and condenser with a Pertronix ignition system and "flamethrower coil". The electronic ignition seems to have improved the cold start and the smoothness of running when hot. Starting when hot is still an issue. It usually needs to cool an hour or two before it wants to start easily

The addition of electronic ignition also seems to make the tractor more sensitive to the choke. I used to crank it a few seconds with full choke, then without choke then with the choke again. Now it seems like it wants to start just as I release choke. While going through that start process, the tractor never seems to give a warning that it's ready to start (like coughing or sputtering) right up to the second it actually starts suddenly.

Two questions:

1) What should I check next to help it start more easily

2) Is there a specific procedure or sequence I should try on the start. i.e 1/4 throttle, a few revs without choke, then choke for a few revs etc.

I thought saw a starting procedure on this forum specifically for this tractor but I can't seem to locate it again. Maybe I saw it as a general procedure not specific to this Ford? Thanks

Ed

what? EI didn't solve al the problems? say it ain't so! That defies all logic!


The truth is.. you really should fix a tractors problems before doing things live voltage conversons.. and ignition conversions. or you get stuck with a machine with a converted ignition and the same problems. ANd like you saw. the ignition benefits while they did help some.. did not solve the other problems.

1, ensure good spark on all plugs. if you got that. move on to fuel system.

post back after checking spark.

Thanks for the quick response. I'm not an expert and probably didn't make all of the decisions in the way an expert would. That's why I came here looking for help.



The process I went through before deciding to go to electronic ignition are as follows:

* When I started investigating the problem and determined I had intermittent spark at the points, the tractor had stalled in the field. I cleaned the points gapped them, cleaned the distributor and rotor cap and checking for loose wiring connections. Each time it seemed I had restored even a weak spark at the points, the tractor would start and run for a few minutes before stopping. I was unable to get it to run long enough to get it back to the shed.

* During a lot of cranking I ran the battery down. At the low end of the battery's charge I noticed a spark jump from the power terminal on the starter. I removed the battery and put it on the charger and tightened the terminal on the starter. The charger read about 5 amps draw initially and moved to around 3 amps after charging overnight but never dropped to lower than that. I assumed the battery was probably in need of replacement in the near future but I did not replace it at that time.

* I read some things on this forum and decided to switch to the electronic ignition. After installing it, the tractor started more quickly than it had recently and ran much better with the exceptions I noted on my original post.

p>I've explained this since your response seems to imply that the electronic ignition was changed on a whim rather than with any preliminary troubleshooting.

Going from stuck in the field for a week to running but seeking additional improvement seems like an OK choice to me.

I appreciate any specific suggestions based on my original post or follow-up that would help me further the improvement to the operation of this tractor.

I will, as you have suggested, check for spark on all cylinders and report back. Thanks for your response/help.

Since you still have a 6 volt system, your ground should be on the positive (+) side of the battery. Make sure the short small wire from the coil to the distributor is on the (+)ground side of the coil.

I noticed that the spark at the points was occurring only intermittently


Two questions:

1) What should I check next to help it start more easily

2) Is there a specific procedure or sequence I should try on the start. i.e 1/4 throttle, a few revs without choke, then choke for a few revs etc.

Click to expand...

Firstly, there should NOT be a discernible 'spark' at the points....
The condensor is supposed to suppress this spark,
so that your points don't burn up prematurely.

Given the electronic switch, that is now a moot point,
but I had to clarify it.

Secondly, cleaning the distributor cap and rotor is only an interim
solution to bad cap and rotor.... Replace 'em.

Per your question #1, and ASSUMING the cap rotor and plugs are in
good condition, the ignition timing should be checked.
Also, the interior of the distributor, advance weights, springs,
for sloppy operation.

For question #2, starting is certainly going to be a result of
correct position, AND good condition of aforementioned parts, and coil.

This starting technique has always worked for me on carb engines.....

Pull choke full out (hard)
Throttle FULL
Crank a second or two and engine SHOULD fire (sputter)
Immediately push choke in about 1/2,
reduce throttle, and let warm up.
After 5-10 seconds or so. you can eliminate choke
(maybe longer in winter)


Unfortunately, todays typical computer driven systems are supposed
to take the guesswork out of starting, since there are no chokes, etc.,
and the fuel delivery is automatic for starting conditions.


(when I'm President, everybody gets a Model A ford
few wires, no computer, etc. )

.

Little Billy,

Thanks for the input. The distributor cap and rotor were pretty new (a year or maybe two old) as were the points and condenser. There was a little bit of carbon on the distributor cap pins but I've seen a lot worse. The rotor cap was pretty clean and didn't have any carbon on it but I brightened it a bit more with fine sandpaper. The points didn't appear to have any build up or burnt spots on them but I've had situations on this tractor where the points looked clean but it wouldn't start until I cleaned them further.

I'm definitely going to look at the timing since the tractor also tends to run hot after an hour of bush-hogging. I've flushed out the radiator and replaced the thermostat in the last year or so. I don't have a fan shroud on it so I'm considering adding one. I've recently got rid of my 72" bushog which I think was a bit much for this tractor. I'm trying to approach the cooling issues in a rational step by step way but I haven't got to the bottom of that yet.

I didn't check the distributor other than to check the copper/brass flat ribbon that used to electrically connect the points to the post on the distributor shell and to give the shaft a shake to see if there was any wear or play in it. I believe the distributor is the 58 year old original so it's possible that's an issue. It generally looks pretty clean inside.

I'll give your start procedure a try. If it works for me you'll have my vote for President.

Black paint on the Model A will be OK for me. I don't prefer black cars because they tend to show the dirt the most but I'm willing to do it if it keeps the cost down.

Thanks

Ed

Even when perfect...


These tractors are updraft carbs and gas fumes are heavy so....

When hot.

You should have the throttle set a bit above an idle..

crank engine,,, while pulling the choke all the way out, and then easing it back in a bit after half a second cranking.. if it doesnt fire, keep cranking for two seconds, then pull the choke all the way closed again for one second and move it back to half choke....

This will make the tractor suck up the heavy vapor into the engine and fire off much quicker.

updraft carbs where installed to keep the bad floats from pouring gas into the engine when the tractor was parked.