I have my car on stands for a while so I decided to check my 123 distributor for the oil invasion problem noted by @adawil2002 and others on the internet, as well as clean out any debris. It comes apart rather easily, drive out a shaft pin to remove the aluminum flywheel then remove 5 hex screws to remove the top green plate. The bottom green plate has all the electronics and wiring imbedded in it and I only (gently) pulled that out of the way to check the bottom of the housing.
Fortunately no oil, and the small amount of sandy debris that managed to get in was cleaned out. I had a slightly concerning issue reassmbling the flywheel and pin but it was my error and got it back together having flirted with fixing something that wasn't broken. I noticed the flywheel magnets had plating that was flaking off so I smeared a small amount of JB weld on both sides of each one to keep more from falling into the housing.
There isn't really a definitive guide to installing these for the first time, I find the 123 manual lacking because it doesn't mention what I found to be an important detail, and that is once the engine is at TDC for cylinder 1, the 123 should be installed with the rotor pointing at the #1 plug on the cap. It doesn't say this in the manual and implies position doesn't matter. Maybe it does and I just didn't do something right. But I think it does matter because it would pop and backfire like hell until I did so. And they don't say that after the green light goes on and you are ready to fire it up, if it doesn't start the first time (which I have read is quite common, including me) then advance the distributor a centimeter or so at a time until it does. Once it starts and the engine warms up, the engine must be manually timed with a timing light to the same spec as in your curve. So if you have initial timing set in the software at 15 degrees at 950 rpm like I do, the engine needs to be manually timed to this by rotating the distributor and strobing the flywheel window. This isn't documented either that I could find. Hopefully someone who gets one of these amazing pieces of technology and is having trouble installing will find this helpful. Anyone else had to do this?
I also fiddled with a new curve. I have triple webers and many users say they like lots of early advance so I have a fairly steep curve and decent amount of static advance. My idle advance at 950rpm is 15 degrees. I bumped up the advance to max 20 if the car idles below 850 as a way to prevent stalling (sometimes my engine wants to stall if I go into stop and go traffic after running fast for a while and its a very hot ambient temperature weather, I think it has to do with fuel mixture etc, not really a problem but maybe this will help. Also when I tried it on a cold engine it actually kept the idle up without having to hold the accel pedal while warming up (no cold idle circuit on side drafts). So no advance when cranking, higher advance when warming up or if idle gets too low, then a normal curve from 900 on. My idle is set at 950. I don't use vacuum advance. Pretty cool so far. Give it a try and let me know if it works for you, and any other installation notes to post here.
Fortunately no oil, and the small amount of sandy debris that managed to get in was cleaned out. I had a slightly concerning issue reassmbling the flywheel and pin but it was my error and got it back together having flirted with fixing something that wasn't broken. I noticed the flywheel magnets had plating that was flaking off so I smeared a small amount of JB weld on both sides of each one to keep more from falling into the housing.
There isn't really a definitive guide to installing these for the first time, I find the 123 manual lacking because it doesn't mention what I found to be an important detail, and that is once the engine is at TDC for cylinder 1, the 123 should be installed with the rotor pointing at the #1 plug on the cap. It doesn't say this in the manual and implies position doesn't matter. Maybe it does and I just didn't do something right. But I think it does matter because it would pop and backfire like hell until I did so. And they don't say that after the green light goes on and you are ready to fire it up, if it doesn't start the first time (which I have read is quite common, including me) then advance the distributor a centimeter or so at a time until it does. Once it starts and the engine warms up, the engine must be manually timed with a timing light to the same spec as in your curve. So if you have initial timing set in the software at 15 degrees at 950 rpm like I do, the engine needs to be manually timed to this by rotating the distributor and strobing the flywheel window. This isn't documented either that I could find. Hopefully someone who gets one of these amazing pieces of technology and is having trouble installing will find this helpful. Anyone else had to do this?
I also fiddled with a new curve. I have triple webers and many users say they like lots of early advance so I have a fairly steep curve and decent amount of static advance. My idle advance at 950rpm is 15 degrees. I bumped up the advance to max 20 if the car idles below 850 as a way to prevent stalling (sometimes my engine wants to stall if I go into stop and go traffic after running fast for a while and its a very hot ambient temperature weather, I think it has to do with fuel mixture etc, not really a problem but maybe this will help. Also when I tried it on a cold engine it actually kept the idle up without having to hold the accel pedal while warming up (no cold idle circuit on side drafts). So no advance when cranking, higher advance when warming up or if idle gets too low, then a normal curve from 900 on. My idle is set at 950. I don't use vacuum advance. Pretty cool so far. Give it a try and let me know if it works for you, and any other installation notes to post here.
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