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TexasKnucklehead
02-23-2008, 12:27 AM
My flame thrower coil and pertronix ignitor both arrived and I thumbed through the installation instructions and have a couple concerns. My 74 TR6 has a "ballast resistor wire". The Lucas coil has the lucar type connectors, while the flame thrower has threaded posts. I suppose I'll find some lucar ends to bolt onto it so I can plug the wires with lucar connectors onto them. Since the ignitor also has lucar connectors on the wire ends, I guess I can plug the red wire into an open spot on the fuse box that is switched with the ignition (since I have the resistor). The coil instructions say to remove the resistor for racing and keep it for normal applications. If I remove it, do I replace it with a wire? If I plug the ignitor to a switched hot, does it matter?

But, look at the attached picture and tell me what I have inside the red box. I'm guessing it's some sort of noise eliminator or suppressor or something. It's not on any of the schematics I have. Do I continue to use it, or remove it? It's connected to the negative side of the coil and bolted securely with the coil to the engine.

The instructions say to set the timing as usual. This change shouldn't change the timing, but the last time I set it, was using an ohm-meter and turning the motor by hand since my timing light died. I guess I'll need to get a functioning timing light.

TR3driver
02-23-2008, 02:36 AM
I suppose I'll find some lucar ends to bolt onto itShould be readily available at any decent electronics supply. Or MMC P/N 8015K51
https://www.mcmaster.com/<div class="ubbcode-block"><div class="ubbcode-header">Quote:]If I remove it, do I replace it with a wire? If I plug the ignitor to a switched hot, does it matter?[/QUOTE]Yes, on both counts. The coil has to have power, as well as the Ignitor.<div class="ubbcode-block"><div class="ubbcode-header">Quote:]I'm guessing it's some sort of noise eliminator or suppressor or something. It's not on any of the schematics I have. Do I continue to use it, or remove it?[/QUOTE]Good guess. I'd leave it disconnected unless you have trouble with radio interference.<div class="ubbcode-block"><div class="ubbcode-header">Quote:] It's connected to the negative side of the coil[/QUOTE]Don't you mean the positive side ?<div class="ubbcode-block"><div class="ubbcode-header">Quote:]The instructions say to set the timing as usual. This change shouldn't change the timing, but the last time I set it, was using an ohm-meter and turning the motor by hand since my timing light died. I guess I'll need to get a functioning timing light. [/QUOTE]You can still do it the other way, if you want, IMO. Just don't take TOO long doing it. Pertronix warns that the coil can overheat if you leave the key on with the engine not running, but it should take quite some time for that to happen. 5 minutes should be no problem.

TexasKnucklehead
02-23-2008, 03:05 AM
Oops, You're right, it's on the positive side.
Thanks.

I'll drop by a parts store in the morning, but I bookmarked McMasters -they sell everything. I considered cutting off the lucar connectors and crimping on some lugs, but that would almost defeat the purpose of having the old stuff in the glove box if the ignitor went dead. The terminal size (width) is different between the ignitor ends and the original wiring. Sometimes I over complicate things, and sometimes they are already over complicated.

02-23-2008, 05:00 AM
TK, Randall is right on about leaving the ignition on with the Pertronix. You <u>will</u> cook the electronic ignition and be stranded. One of the few downsides to switching over. I have seen it happen in 2 minutes flat with a Crane setup. Looking closely, seems your wiring is very much original and just a little crusty. Is that wire to your original coil a bit frayed? Be careful striping old wires to attach new connectors, will often be a lot of corroded copper near the end. Soldering is usually better. New harness in your future? Are those the original Lucas spark wires?

TR4nut
02-23-2008, 09:58 AM
Jerry-

Check the flamethrower box again first. I just got mine from TRF yesterday and I think there is a packet of lucar fittings to tie to the posts. Not in the garage at the moment, but I can confirm if you want.

Randy

KVH
02-23-2008, 11:56 AM
What are those funny pink things on the top of your picture? Could those be the source of some problems?

martx-5
02-23-2008, 01:55 PM
What are those funny pink things on the top of your picture? Could those be the source of some problems?

Without a doubt!! Whenever those things get involved, it's almost certain something will go wrong. :jester:

2wrench
02-23-2008, 02:28 PM
What are those funny pink things on the top of your picture? Could those be the source of some problems?

Dactyl scope, or dactyloscope. Common household tool for the
diagnosis/repair of British Cars. Could be referred to as phylangealoscopes.

Oftentimes as much the problem as it is the cure for our British car
woes. Comes in two versions, left-hand as well as right-hand. Tool can
be utilized left only or right only; but quite commonly most effective
if both are used in unison. Not available in the stores.

TexasKnucklehead
02-23-2008, 11:22 PM
Bill, I may have the original wiring, but the only bad looking wire is that "ballast resister wire". It looks as though that wire has overheated at some point and the insulation is a little baggy at the end. Other than signs of paint over spray, the other wires look pretty good. I soldered my new connectors onto the ignitor (I always solder crimp connectors).

Randy, I checked the box (and the one from TRF) but there were no nuts or connectors. Just as well, I got some terminals from RadioCrap and modified them so I can simply plug the old unit on in the case of an emergency. (The plugs on the ignitor were narrower than the rest of the TR6 ones, and the connector to the points is male, instead of female.)

Generally, I'm a "aint broke, don't fix it" type, but I do a bit of PM. Changing the points, condenser and rotor got those pink things into the picture a few weeks ago and got my knuckle head involved. After todays work I was able to test drive for at least an hour, that seemed like a few seconds, without any issues. Car runs great again, but I wish I knew what was wrong when it kept dying.

The old coil (1.5ohms) has some oil droplets on the bottom, but I'm assuming that was simply oil seeping from the mounting bolts (since one was pretty grimey).

Overall, the conversion wasn't as simple as expected. Aside from not having the correct terminals on the coil or ignitor, the coil is slightly more round so the bracket needs a longer screw to grip the coil. Then the holes in the bracket need "stretched" because they no longer line up. The car does start instantly, and seems to run fine, and I'll never have to wonder about bad condensers or worn points again.

Life is good. I put at least 40 miles on today in the sun with the top down. I'm glad I'm not the only one with a sense of humor. Until I read "phylangealoscopes" I was starting to think I was being accused of having my hands involved with the problem.

poolboy
02-23-2008, 11:34 PM
I'd be surprised, Tex, if you didn't need a little adjustment of the timing. Seems like the Pertronix pick-up is oriented a little different than points as related to the Dizzy's cam.

TexasKnucklehead
02-23-2008, 11:46 PM
Pont taken. I'll find a timing light and check the timing. When stuck at a red light in a long line of cars today, I noticed the temperature climbing a little. That usually only happens when it's way over 90 so maybe the timing is off a little. Thanks.

poolboy
02-23-2008, 11:58 PM
Yeah, it happened to me too after the install. Engine ran smooth enough but was noticeably lacking the power. Thought I really messed up. Advanced the timing, That did it. Really did not advance it any more than it was with the points, just "reoriented" the dizzy.
I've given up on the timing light except to get a reference mark after setting the timing by test drives.
I figure that slack in the timing chain, the sprockets and the dizzy drives pretty much make the timing marks on the damper a very rough estimate of where the piston really is relative to spark.

TexasKnucklehead
02-24-2008, 12:05 AM
I'm not sure I follow you. How do you "reorient the dizzy"? And after you do it, how do you know it's correct or better?

poolboy
02-24-2008, 12:30 AM
Sorry, that's just a term I used. In other words, I had to turn the dizzy in the advance direction to get the timing back to where it was before the Pertronix was installed. That's what I meant by "reorienting" it.Turn the dizzy in order to compensate for the location of the "pick up" vs the location of the points as related to the dizzy cam (lobes).
As far as knowing that the timing is right, if you did use a light to set it with points then use it with the Pertronix.
I just found that if I use the timing marks on my engine with 98k miles all the wear that has developed since new leaves me with a seriously retarded engine.
So, I do it by ear, test drive and use a vacuum gauge on the intake manifold to get max vacuum. Usually it is right by the time I test drive and listen to the engine. If you fool with it enough you'll get a feel for the sound, smoothness and power.
But, like I said, if you do have a reference mark with the light that you trusted before with the points, then turn (reorient) the dizzy until you get back to that spot.

TexasKnucklehead
02-24-2008, 12:42 AM
Right. Thanks for clarifying. I didn't use a light to set it last time. I had the battery disconnected, and used an ohm meter. With the Pertronix, I'd have to have power on. I have seen several posts regarding powered units without running engines and the possibe side effects (pertronix burning up). So, I'll try a light this time, and get an idea where it is now, and then fool with it to see if it can be improved.

You're proabbly right that the new unit isn't exactly the same as the old, regarding timing/orientation.