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ah, could be it sat all winter and got some moisture in the cdi box then shorted out when you dropped the batt. back in. did you re-wire anything over the winter, mighta crossed a wire when putting it back together
ah, could be it sat all winter and got some moisture in the cdi box then shorted out when you dropped the batt. back in. did you re-wire anything over the winter, mighta crossed a wire when putting it back together
LOl OH yea, I re-wired what is left in there...3 guages, the CDI box, and the start/ignition circuit. I have a background in Avionics Electrical, so I know it was done right. The dash was done on the workbench, then the CDI was incorporated in after I installed the dash.
There is always that possibility, but I can't see where.
I might have to go with a HEI module if I can find a heatsink big enough, there are no real computer repair shops in this small town
heat sink, Computers Networking, Toys Hobbies. Great deals on eBay!
cheap on ebay there are some big uns on there should do the job.
thats a pretty cool job, my great great uncle was a radio and avionics tech/teacher in the navy WWII. he gave me a whole bunch of old electrical books and manuals. he also gave me a cool OLD multimeter
I have used the tfi setup and used the 4 pin gm module,
and if either crapped out I tossed the old cap and rotor back on
and hooked the wires back up to bypass the module.
Never had to do it as the large cap "tfi" setup with coil worked just
perfect.
LOl OH yea, I re-wired what is left in there...3 guages, the CDI box, and the start/ignition circuit. I have a background in Avionics Electrical, so I know it was done right. The dash was done on the workbench, then the CDI was incorporated in after I installed the dash.
There is always that possibility, but I can't see where.
I might have to go with a HEI module if I can find a heatsink big enough, there are no real computer repair shops in this small town
There is nothing basically wrong with the motor craft module, it's the folks that are making them we have a problem with. The after market motor craft have a very dismal reputation for their quality. I do remember when they were "good" and they cost about three times as much as well. The prestolite only happened in 76 and 77 and it was a relatively dependable system and was state of the art some time just after WWll. in other words it is a dinosaur and it is in major need of modernization. It's pretty easy and you can do it with stock jeep parts.
I'm sure the HEI works well, I have not done one myself. I do have a problem with electrical parts hanging out in front of everybody. I have not seen an acceptable meathod of mounting one yet and I have no good ideas myself.
No reference just thought I remember reading that the stock module would not last long with the TFI coil. My 78 has the Motorcraft module, is that a better unit than the Prestolite?
I have used the tfi setup and used the 4 pin gm module,
and if either crapped out I tossed the old cap and rotor back on
and hooked the wires back up to bypass the module.
Never had to do it as the large cap "tfi" setup with coil worked just
perfect.
never had to fix one on the trail but sitting in a parking lot when the coil crapped out. it was very easy 4 screws on top of the cap unplug the connector, pull the coil up and out drop new coil in, insert wires back into the plug. put coil cap back on replace 4 screws. to change an ignition module turn the 4 spring loaded clips remove plug from cap, take cap off leaving all plug wires in place, take 2 screws out of the rotor button, remove rotor button, take 2 screws out of control mod. remove ign mod plugs, assembly reverse of disassembly. takes 10 min to completely tune up a hei. all while hardly leaning over the fender
sorry but an hei is not difficult in the least bit to repair. i take that back it can be a bit of a hassle if you are sitting on the motor of a lifted 79 chevy. but so could anything else
Yea I know, thats what I have...I've been thru 2 CDI boxes on this thing and I'm getting tired of replacing them.
<rant on>
When I drove the Jeep into the garage last fall I had no issues. Now after putting it all back together, I found out last night the CDI box melted something inside. Now how could it have done that when I pulled the battery while the engine was still hot, and it hasn't had any wiring in it all winter? There is only 1/2 dozen wires in the whole thing now... Oh well, It just means I'll miss the race this year unless I can figure out another ignition system pretty quick...
<rant off>
omg my thread been hijacked lol..... oh well i can say i am learning a lot from you guys. but any ways here the update after fixing the vacuum leak and resetting the timing i drove it to work today and its drives a lil better the idles is way better..... but i got to replace the carter carb soon... so it still runs crappy just with the bad carb on it... think once i change out the carb and put in a tfi coil it should run better than new. but really will putting in a tfi coil be better than running a high voltage regular coil?
omg my thread been hijacked lol..... oh well i can say i am learning a lot from you guys. but any ways here the update after fixing the vacuum leak and resetting the timing i drove it to work today and its drives a lil better the idles is way better..... but i got to replace the carter carb soon... so it still runs crappy just with the bad carb on it... think once i change out the carb and put in a tfi coil it should run better than new. but really will putting in a tfi coil be better than running a high voltage regular coil?
Good to hear you made a little progress, I know with mine I made small steps each time to make it run better as it was a number of different issues going on.
It is kinda nutty these guy's can take a vacumm leak and turn it into???
Opps I see I am guilty too! it is still ignition related though and not very far off course at all this time.
never had to fix one on the trail but sitting in a parking lot when the coil crapped out. it was very easy 4 screws on top of the cap unplug the connector, pull the coil up and out drop new coil in, insert wires back into the plug. put coil cap back on replace 4 screws. to change an ignition module turn the 4 spring loaded clips remove plug from cap, take cap off leaving all plug wires in place, take 2 screws out of the rotor button, remove rotor button, take 2 screws out of control mod. remove ign mod plugs, assembly reverse of disassembly. takes 10 min to completely tune up a hei. all while hardly leaning over the fender
sorry but an hei is not difficult in the least bit to repair. i take that back it can be a bit of a hassle if you are sitting on the motor of a lifted 79 chevy. but so could anything else
i'll bet you $10 i could replace the cap, rotor button, coil, and control module before you can get the bolts out the fender to change the motorcraft mod.
Not to thread jack but I installed a Jacobs Mileage Master ignition pak and coil on my 78 CJ5 about 10 years ago. It was a real wake up for the old AMC 304 !
Anyone remember those ignitions? I think the were bought up by Mallory...
i'll bet you $10 i could replace the cap, rotor button, coil, and control module before you can get the bolts out the fender to change the motorcraft mod.