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i am burning my rotors

Guest Anonymous

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Guest Anonymous


I keep burning my distributor rotors. It only takes a few munites of driving and the part that looks like it was poured in melts and some white stuff comes out and hardenes back into plastic. it looks like i am overheatin it. I have prtronix ignitor and Crane HI-6 with LX-92 coil. W8DC spark plugs and 8mm wires.

Any idea what can cause this? The car runs fine after this melt down.

steve k.

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Guest Anonymous

switch your cap(and rotor). Sounds like you have too much gap between your cap and top of rotor.

I've run simular setups and havn't had any trouble like this.

and a duh idea: make sure cap is firmly seated on dist. body... (just maybe...)

best of luck with it. b

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Guest Anonymous

with all due respect:

I know you've probably checked this, but I just

found out that my cap doesn't fit well, causing the

rotor to score the cap. maybe this leads to your


could be?

Brent Miller

'71 1600

'86 535i

'85 735i

Little Rock, Arkansas

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Guest Anonymous

Your uprated coil and trigger are not the root cause, they only allow a higher reserve voltage for when the plug requires it to fire. If the plug is ready to fire at 8kv breakdown voltage, it will. It does not matter that your coil is capable of five times that.

The above assumes that your secondary ignition is OK. In normal condition, the gap for the plug is much harder to fire than the air gap between the rotor & cap, because the spark plug sees much tougher working conditions (high temps & pressures, or mixtures either side of stoich need higher voltage).

Your rotor looking like it melted is a sign that more engergy than usual is being used there. Likely this is where the problem is. You have a larger air gap somewhere in the cap/rotor interface, and your hot coil has enough reserve to compensate.

Check the cap to see if the carbon button (on a spring) is present at the top center.

Check the fit of the cap on the dist, does it locate itself with a matching notch? If you have an 002 mech dist, you need a 3010 cap (not the one for an OE tii mech dist).

Check the rotor, does it fit on the shaft at the correct height? Does the dist shaft play allow the rotor to rise up?

There's not much to go wrong there if you have the correct dist/cap/rotor in good condition.

You could also check the rest of the hi-tension side:

The 02's secondary ignition parts are designed with suppression resistance in the following:

5k @ Rotor

1k @ Plug Connector (on plug wire)

1k @ Dist Cap & Coil Connector (on plug wire)

You do not want suppression resistance on the spark plugs or plug wires. I've seen Bosch wire sets sold with resistance wires (like 10k ohm per ft).

What combination of parts do you have?

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Guest Anonymous


I've run into this before... There is a compatible rotor with an internal resistor (from a VW application)that'll solve this issue. Call me for more info.



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