wiring help

[bls33]

I'm just finishing the most frustrating engine swap I've ever done and have some wiring issues, The engines is a 360 from a 77 Chero, and its going into an 85 CJ-7 that had the 258

so I was looking through all the wiring and decided that I'll call up my buddy to help, due to the fact I suck at anything electrical, and really didnt know what I was doing. So he comes over and says there were some of components i should have taken from the donor vehicle, dont have the specifics but I remember stuff about modulators. The thing is I no longer have my donor vehicle, so what do I do? I've done swaps before but someone else always does the wiring.

So plese someone enlighten me as to what I should have taken from the donor vehicle so I can see if I can get a hold of it from somewhere else. Sorry for the lack of specific info but plese help me

[tufcj]

If yours has the Prestolite distributor, toss it. It has a plastic vacuum advance with 2 bulbs, they are very unreliable. Go find a 79 or newer Motorcraft distributor. The Motorcraft will plug into your existing harness, and use the existing ECM.

Other than maybe re-using the alternator for the 6 cyl, the rest should be just lengthening and rerouting some of the wires. The fuel line will need to be lengthened/rerouted.

Bob
tufcj

[FuzzFace2]

If yours has the Prestolite distributor, toss it. It has a plastic vacuum advance with 2 bulbs, they are very unreliable.
Bob
tufcjI always hear that but have yet to found out why?
Is it the vacuum advance unit, mechanical advance or the pick up inside?
Don’t think it’s the box as the dist is just a trigger unit.
Can some one tell me why it’s junk?
Dave ----

[bls33]

If yours has the Prestolite distributor, toss it. It has a plastic vacuum advance with 2 bulbs, they are very unreliable. Go find a 79 or newer Motorcraft distributor. The Motorcraft will plug into your existing harness, and use the existing ECM.

Other than maybe re-using the alternator for the 6 cyl, the rest should be just lengthening and rerouting some of the wires. The fuel line will need to be lengthened/rerouted.

Bob
tufcj

thats sounding about right becaudse he did talk about there being a problem with the distributor hooking up, while he was trying to explain this all I was putting a carb back togetehr thats why I'm fuzzy on what he said.

So if it is a prestolite it could be why the wiring isnt compatible and why he said I was missing stuff from the donor vehicle

[jeepsr4ever]

Their is a purple wire that is used with the Motorcraft distributor that comes off the ignition control module. Without this wire hooked up you will not get power. Look on your module located on the drivers side fender and find the purple wire and cut and splice it into the distributor plug. You may actually need a V8 distributor plug or simply splice the wires. Now may be a good time to switch to a HEI...which is plug and play but if not it isnt much hassle to wire up the 8

[bls33]

an HEI distributor sounds like a good idea, will the old ignition module work with it?

[ironman_gq]

you dont need an ignition module with HEI its built into the dizzy you only need to run a switched power wire to the dizzy to make it work. make sure the wire has power only while the key is on or you won't be able to stop the engine

[bls33]

you dont need an ignition module with HEI its built into the dizzy you only need to run a switched power wire to the dizzy to make it work. make sure the wire has power only while the key is on or you won't be able to stop the engine


ohhhh alright, very cool sounds like the easiest thing to do. I will order one tonight most likley. Thanks for the help fellas!

[FuzzFace2]

You could also keep the dist. you have now and get an MSD type box it just needs a trigger an the dist you have now would work.
Dave ----

[tufcj]

There were 2 problems with Prestolite. The vacuum advance diaphram would rupture, then they would pull gas out of the crankcase around the shaft. If the mixture was right, it would ignite inside the cap and blow the cap right off the distributor (I've seen it happen). The second problem was the Prestolite ECM. They were prone to failure. My 77 CJ had 4 of them fail before I swapped to a Mallory (4 failures over about 6 years). I carried a spare in the glove box. I'd be driving down the road and it was just like someone just turned the key off, absolutely no warning.

Bob
tufcj

[FuzzFace2]

Thanks for the reply
I had to replace the vacuum unit on my 75 Gremlin when I first got it 10+ years ago.
You know I am fighting that same thing for years now. I have replaced the box (ECM) so I don’t think that is it. When it dies you never have testing tools with you, well now I do but think it’s the pick up in the dist. The car is all stock 64k so I hate to start cutting it up.
Dave ----

[bls33]

well shes all wired up, and I fired it up for the first time in weeks yesterday with the exhaust all hooked up, hedman headers to purple hornies and man does it sound MEAN :shock: sounds great though

I did find out that my dipstick tube was cracked :(: so I need to find a new one, if i find one thats compatible today at napa or where ever I'll be all done today :!:

[Patf10]

not thread jacking but will the alternator from the I6 fit the V8, in a CJ. Im doin the swap and im getting stuff together and need to know. and my alternator is a 1 wire so that would be nice !

[tufcj]

You won't find anything at an auto parts place. They might be available in the online store here. They are still available from Jeep dealers, or on ebay. The repros do need to be ground down slightly where they swedge into the block.

The old tube can be a pain to remove. I've used a slide hammer with a sheet metal screw, and I've heard of making a hook out of coat-hanger to slide thru and catch the bottom.

When you put the new tube in, do it with the dipstick inside, to be sure it passes thru the hole in the pan baffle.

Bob
tufcj