I've been struggling for a while with the stock distributor on my 79 FJ40 project that had been sitting for over a decade and abused before that.
I got the distributor freed up and cleaned up, so that it started and seemed to run ok, but always a bit rough. In the process of cleaning I noticed a small amount of slop in the distributor shaft, coinciding with the mating to the cam gear. It seems the bushing may be slightly oval-shaped in that direction. A member here suggested that slop would be fine. Just adjust the air gap on my pickup accordingly, which I did and it ran, albeit roughly.
Today I dug a bit deeper and discovered I had no spark on #5 cylinder due to a distributor issue. When I opened the well-used cap I saw this -
Looks weird, right? Seems like a lot of carbon for only a few hours use.
The no-spark cylinder, #5 is at 11 o'clock. Notice the carbon at the top and bottom of the screen and clean terminals at either side. This seems to correspond to the distributor shaft slop top-to-bottom, and it being tight side-to-side.
BTW, that oem cap came with the vehicle and is very used and poorly repaired. There were previous carbon traces and gouges from an aftermarket rotor. I have one clean aftermarket cap and rotor, but don't want to use it until I get the bushing slop eliminated, because these caps and distributors were only used on two model years (79 and 80) and have become a bit rare.
So, my options seem to be:
- Replace the bushing on my oem 79 distributor. Any recommendations on who might do this?
- Substitute a cheap aftermarket electronic distributor. I have one on the shelf, but don't want to use it because it's not water resistant. However that's probably my next step in the short term just to get my 79 running properly.
- Upgrade to a big cap distributor and dimpled pushrod cover from a later FJ40 or FJ60. This is my preference long term. I just put up a new classified ad looking for one. Let me know if you've got one laying around.
One more thing I'm wondering about is, does that excessive carbon buildup in the cap indicate any other ignition issues? I'm using the stock coil, igniter with Yazaki ignition wire, and have rewired some of the ignition circuit to hopefully match the schematic.
However, today I checked voltages on the primary and got 7v with the ignition switch on, around 10v while cranking and a little over 12v while running. I was thinking the primary voltage should drop back to 7v when running to improve the life of the coil and reduce arcing? Is that 12v contributing to the arcing in the cap? If so, where should I look to correct this?
Any suggestions on any of this?
I got the distributor freed up and cleaned up, so that it started and seemed to run ok, but always a bit rough. In the process of cleaning I noticed a small amount of slop in the distributor shaft, coinciding with the mating to the cam gear. It seems the bushing may be slightly oval-shaped in that direction. A member here suggested that slop would be fine. Just adjust the air gap on my pickup accordingly, which I did and it ran, albeit roughly.
Today I dug a bit deeper and discovered I had no spark on #5 cylinder due to a distributor issue. When I opened the well-used cap I saw this -
Looks weird, right? Seems like a lot of carbon for only a few hours use.
The no-spark cylinder, #5 is at 11 o'clock. Notice the carbon at the top and bottom of the screen and clean terminals at either side. This seems to correspond to the distributor shaft slop top-to-bottom, and it being tight side-to-side.
BTW, that oem cap came with the vehicle and is very used and poorly repaired. There were previous carbon traces and gouges from an aftermarket rotor. I have one clean aftermarket cap and rotor, but don't want to use it until I get the bushing slop eliminated, because these caps and distributors were only used on two model years (79 and 80) and have become a bit rare.
So, my options seem to be:
- Replace the bushing on my oem 79 distributor. Any recommendations on who might do this?
- Substitute a cheap aftermarket electronic distributor. I have one on the shelf, but don't want to use it because it's not water resistant. However that's probably my next step in the short term just to get my 79 running properly.
- Upgrade to a big cap distributor and dimpled pushrod cover from a later FJ40 or FJ60. This is my preference long term. I just put up a new classified ad looking for one. Let me know if you've got one laying around.
One more thing I'm wondering about is, does that excessive carbon buildup in the cap indicate any other ignition issues? I'm using the stock coil, igniter with Yazaki ignition wire, and have rewired some of the ignition circuit to hopefully match the schematic.
However, today I checked voltages on the primary and got 7v with the ignition switch on, around 10v while cranking and a little over 12v while running. I was thinking the primary voltage should drop back to 7v when running to improve the life of the coil and reduce arcing? Is that 12v contributing to the arcing in the cap? If so, where should I look to correct this?
Any suggestions on any of this?
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