New distributor condensers failing

[Hammbone]

Hi folks, I'm having a new problem with my 51 8n. I Recently replaced the old worn out distributor and refreshed all the electrical connections and it has been starting and running great since(about 20ish hours on new distributor).

The problem that has started since dist. replacement is failing condensers. They seem to be lasting about 5-6 hours before failing. I'm now on the 4th condenser since replacing the distributor.

They aren't very expensive to replace, but it's annoying to have to replace them so often and I had hundreds of hours without condenser failure before distributor replacement. What could make the tractor start eating condensers?

 

[i7win7]

Check voltage going into distributor should be around 6 volts (goes to almost 12 when cranking starter). Did you replace a resistor wire with regular wire?

 

[Roadworthy]

If you did not bypass your ballast resistor it is possible it failed but I've never known one to fail shorted, they always open in my experience. You could also investigate going to a breakerless ignition if such a thing exists for the 8N (and it's popular enough they may).

 

[Hammbone]

Roadworthy, I do not have and also did not bypass a ballast resistor but I don't believe the late model side distributor 8ns used one in the first place.

K7, I have been using the tractor supply co. Point/ignition kit since I had the tractor. Before changing the distributor the points would wear out after 80ish hours and I would replace the points and condenser. Never had a problem before. A couple of the condensers that have failed were actually old ones from previous points replacements that I kept for spares (glad I did now) I wouldn't say it was running good before, but that was more due to the sloppy shaft wobble and broken advanced weights.

Now, when the condenser is failing the tractor just abruptly dies as though the key is switched off and there is no sign of spark whatsoever. After replacing the condenser it immediately fires back up and runs perfectly.

It doesn't make sense that the parts worked fine before but all the sudden are junk. Something seems to be causing it. The only new parts besides the distributor are the spark plugs wires(yes the countyline 8n specific wires I have also been using the whole time)however I replaced them after the first condenser failed.

 

[ultrarunner]

We had similar with the old Ford Model A condensers... one batch from China simply was not reliable whereas the Made in USA are.

The specific problem is the close proximity to the Model A exhaust manifold and the imports couldn't take the heat.

Don't know if relevant.

 

[RalphVa]

Think I'd replace with an electronic one. Did this on an Alfa. It'd just be a sensor gizmo, primarily.

Ralph

 

[Fuddy1952]

Being a retired electronic technician I'd try this....
If you have or know someone with a capacitance meter check a new/good one to see what it measures (I'm guessing 0.47ufd roughly...but to be sure).
Instead of inside distributor you could mount one outside. It's still across the points...distributor connector to ground.
Then try a quality one, same value.
Otherwise the distributor plate be sure it has a good ground, usually a small braided cable wire there to the case. Be sure distributor itself has a good ground, as well as engine to frame.
And as others said...be sure coil is correct. It may be one needing a ballast, or ballast could have been eliminated and should have one.

 

[Hammbone]

Fuddy, I don't have access to a capacitance meter at the moment but may look into it if this continues. I will check the ground connections again, maybe the new distributor has paint or something insulating the connection to the block. Also going to order a few of the suggested higher quality condensers, however it still seems unlikely to me to be a parts quality issue since I've been using the same ones for years without issue and a few of them were old ones that had been used before. Thanks for the help, I'll let you know if it continues to feed on the condensers, lol.

 

[TractorGuy]

Points type distributors require an internally resisted coil OR a ballast resistor. If you had no external resistor and replaced the coil it's possible you put the wrong type coil on.

 

[RickB]

Points type distributors require an internally resisted coil OR a ballast resistor.

Not true with most 6V systems. The OPs tractor left the factory as a 6V positive ground and does not indicate the tractor has a 12V conversion. Late 8Ns with side mount distributors do not have ballast resistors, early Ns with front mount distributors do.