Re: ford 860 -- trying to figure out what is normal ...

oil foul or soot foul?

if soot fouling... you need to find out why she is rich.

is your air fitler restricted?

when it feels lean, is carb icing up?

when you are having to limp it, get off and check spark. if it has good spark, or cyls pick back up holding ghe wire off them a lil bit, you know the fouling is causing an issue.

How old are the plug wires?

Verify that all are fully seated into the respective towers (coil wire, too). If any are not, inspect the ends for damage.

Dean

Verify that the ignition is spot on before looking to carburetion.

Dean

(quoted from post at 10:59:52 01/21/15) oil foul or soot foul?

if soot fouling... you need to find out why she is rich.

is your air fitler restricted?

when it feels lean, is carb icing up?

when you are having to limp it, get off and check spark. if it has good spark, or cyls pick back up holding ghe wire off them a lil bit, you know the fouling is causing an issue.

Click to expand...

It looks like soot fouling.

I don't think the carb was icing up, as it was around 32F this morning. Is there any way to tell if there is carb ice?

What is the best way to check spark on a tractor?

The spark plug wires look fairly new -- I've only had the tractor a year, so not sure how old they are.

Carb icing is a possibility, it has a venturi.

I quick test for spark van be done holding the wire near the block, otherwise a good way us with an actual spark tester. I believe Bruce and hobo have posted pics of them, and hobo has posted links to one he has used

+32 to+42 with humidity is prime conditions for carb iceing.

(quoted from post at 10:35:56 01/22/15)
+32 to+42 with humidity is prime conditions for carb iceing.

Click to expand...

Interesting -- that is good to know. Probably had humidity as it had just finished snowing (very wet).

I've also been reading about rubber gas lines and in-line fuel filters -- both were on this tractor when I got it. I should probably look at restoring that to more original equipment, check screens, etc.

Pressure=heat, and negative pressure (like the vacuum that exists in an intake) equals loss of heat. So any water or water vapor that exists in your fuel or the intake air when it is close to the feezing point can and will condense and then freeze solid.

Just a followup on this saga ...

Made it through the winter plowing lots of snow. Most of the time I could get the job done, but if I ran it too long, it would eventually quit on me.

This spring after it warmed up, it would hardly run at all. This was good as I could finally troubleshoot problems without running the machine for an hour. I tore the carb off, took it apart. It looked horrible, so had a local shop rebuild it. I also ordered a tune up kit. After I put the carb back on, it would hardly run, so checked spark again -- it was intermittent. Checked the distributor, and everything was corroded, and points looked horrible. Points looked fine when I checked them 8mo ago, so I did not think to check them again over the winter (I'm still learning -- always check the easy obvious stuff first!). After looking at new parts, I discovered the dust cover did not have a gasket or shaft seal, so perhaps moisture was getting into the distributor? I then pulled the distributor. The weights on the cam were all froze up, so cleaned them up. The springs on the weights look very old and seem fairly weak -- how necessary are the springs for proper operation? There was a slight amount of play in the dist shaft, but did not feel up to taking the gear off and measuring tolerances. Also replaced the coil. Put everything back together, got the timing close by pointing the rotor at spark plug #1 with the #1 cyl at top of stroke, then timed it while it was running by ear. After running for a bit and adjusting the carb, its really running good -- perhaps the best since I've owned it.

One minor issue now is the engine seems to rev up some if I've been pulling and push in the clutch and the throttle seems very touchy. Not sure if that is an issue with governor mechanism or something.

Anyway, making progress.