another auto-electrical problem

[ebbtide176]

i don't know beans about 12v systems. and i have a problem getting my jeep to start...<br /><br />it just cranks & cranks, even with starting fluid down the top of the carb. i wonder if when i accidentally left the key in 'on' pos 2x(dammit) it might have been related to this new prob? <br /><br />this thing doesn't seem to have an 'acc' position on the keyswitch. and the coil got really really hot, but nothing smelled, nothing burnt up- i didn't think.<br /><br />now the coil test shows 1ohm on the primary, 7.9k on the 2nd. for a 77' cj7 304ci anyone out there with a good idea? my manual (chilton) doesn't seem to have a resistance test, so before i get all serious & everythang (brew involved), i thought i might check with someone who remembers this kind of situation <br /><br />all (positive)thoughts appreciated - lol<br /><br />i hope this doesn't involve the ign module... i might hafta use the brass hammer on something. but hey!- i did finally get the steering box back in with a new coupling kit, despite all the gremlins involved.

 

[ebbtide176]

Re: another auto-electrical problem

if you've been around a long time, and might only cut the chase down to some search keywords.... <br />schematic<br />skinnywater<br />anyone else out there this time of night<br />djohns<br />homer<br />creature from the black lagoon<br />JB<br />UU<br />jomama<br />derwood<br />castaway(entertainment tangent)<br /> just a thought

 

[denniz]

Re: another auto-electrical problem

try www.amcforum.net

 

[ebbtide176]

Re: another auto-electrical problem

thank you sir. i tried <tech talk> & <general discussion> and didn't find it. good stuff tho <br />(10:37pm)<br />i'm closing down the project for the night. thanx<br />amf

 

[petryshyn]

Re: another auto-electrical problem

Have you checked for spark?

 

[DJ]

Re: another auto-electrical problem

ebb,<br /><br />It needs a few things to run:<br /><br />1. Compression.<br /><br />2. Spark-at the right time.<br /><br />3. Fuel.<br /><br />I'd be looking for #2 especially.

 

[SeaMasterZ@aol.com]

Re: another auto-electrical problem

hey, Im more than just entertainment! I have contributed to the solving of quite a few problems, lol, I just have a better time making people laugh

 

[ebbtide176]

Re: another auto-electrical problem

it is not sparking - will get coil. i have a clearer mind this morning i could not find my jumper wires last night, but found them this morning and was able to jumper everything at the solenoid & coil. thanx

 

[jimchere]

Re: another auto-electrical problem

I'm no expert on the older jeeps but have to ask does it have the old points/condenser ignition or electronic? Being a '77, I'm thinking it might be points. If you leave the key in the on position without the engine running, it will burn up the points. So I would check for spark first, and if there's no spark, pop off the distributor cap and look at your points. Cheap and easy to replace. BTW, when replacing the points, I always replace the condenser too, and set the points gap with feeler gage then touch it up with dwell meter (though the feeler gage method is usually adequate). You should also check your ignition timing with a timing light after replacing the points. My car that has the old points ignition is a '74 VW Karmann Ghia (love those old air cooled flat fours ) Points and condenser set usually goes for less than $15

 

[Northern Eclipse]

Re: another auto-electrical problem

Hey didn't some of this Old AMC/Jeep have a ballist resistor if so may have killed it...I just can't remeber if they did or not...but I did have 76 gremlin that we slammed a 390 into, ended up pumping a rod into the pavement...

 

[ebbtide176]

Re: another auto-electrical problem

its been yrs & yrs since i worked on ign probs. on the way to work i was thinking that i need to do more testing. it doesn't have points. it does use ext resistor but is getting pwr to coil. i was trying to remember- to test the coil only, can't i just pull the ground side off, and use a jumper to grnd momentarily, with coil wire pulled & laying with gap near frame grnd?<br />- i'll just hafta slow down and check it all out. i was in a hurry because my neighbors son wanted me to take him trout fishing tomorrow morning. i was gonna go way off the trail but we can do something else.

 

[jimchere]

Re: another auto-electrical problem

Sorry ebb but my old chilton's in the garage only goes up to '75 (still had points on the 304 then). But, I think you're on the right path, except for checking the coil. First, I would almost do what you say, but just pull off the center spark wire on the distributor cap that comes from the coil, hold that close to a good ground while buddy cranks the motor, and see if you got spark. If not, then check for +12vdc from the primary terminal to ground. Before you drop the dough on a new coil at least make sure you got the 12vdc to the primary side@

 

[Skinnywater]

Re: another auto-electrical problem

Hmm, ebb, does it have points or not?<br /><br />A coil can last the lifetime of the Jeep. Go for the cheap maintenance, wear and tear items first.<br /><br />ebb, more feedback is needed.

 

[ebbtide176]

Re: another auto-electrical problem

hey skinny. well i got in a hurry and that never works. it is a 77 cj7 304ci, which uses the BID ign system (been reading ) this BID uses conventional coil, with proper voltage reg from ign module. i think i actually just need a coil after all... when i did a fast ohm test this morning, i forgot to check everything. the <br />pri=.7 ohm<br />sec= 6.7k<br />-which i thought might be ok. but i found the neg-case grnd is inf, and those other readings should be pri=(1.25-2.4)sec=(9-12k)<br />-and i also verified the pickup sensor resistance is 2ohm=ok(1.6-2.4), wiring from ign mod has :<br />switched pwr<br />continuity to (-)coil<br />cont~ to both pickup sensor leads... <br /><br />-and verified the swtchd pwr to (+)on coil, the coil hi-tension wire=10.22k(5k-10k)<br /><br />what do u theenk?<br /><br />PS: i just verified the rotor/trigger wheel turns with engine rotation<br /><br />PSS: i forgot to mention i did find that the condensor wire was broken - how bad is that? i will def just get a new one since they come with the little pigtail.

 

[petryshyn]

Re: another auto-electrical problem

put a 12v testlight from the coil "-" to coil "+"<br />crank engine over. If the light pulses on and off and you have no spark from the coil tower to ground, then the coil is bad. If the light doesn't pulse, check the pickup coil for proper resistance. If checks OK, module can be bad. Most modules can be checked by taking 2 penlight batteries hooked in series and connecting them to the pickup coil connections to the module (disconnect the pickup coil and insert batteries). When connected, the testlight across the coil primary should go out....If not, replace module.

 

[ebbtide176]

Re: another auto-electrical problem

never heard of the batt idea, and didn't even think about using the test light across coil, makes good sense cool stuff... so i guess that was 3v back to ign mod? good deal, can't crank it any more tonight though. will do it after daylight. (i need to sleep in bed instead of doghouse for strength tomorrow)<br />thanx!

 

[petryshyn]

Re: another auto-electrical problem

3v applied to the module pickup coil terminals is correct. No cranking needed to do this test. Just have the key in the on position. If the light doesn't turn off, also try reversing the 3v battery pack polarity to the module....

 

[ebbtide176]

Re: another auto-electrical problem

well it was the coil after all. 1 thing i noticed, the coil would not receive a grnd via the ign module with the pickup coil disconnected. so i guess it does differ with brands. <br /><br />2 things to remember when you think you burnt up the coil by leaving ign swtchd on(no spark to plugs)<br />-testlight across coil should flash when cranking<br />-testlight on coil(+) should light by contact with coil's case. <br />it seemed that was what actually failed... now for a ujoint replacement