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Unread 06-23-2011, 05:38 PM   #16
jhumphrey
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Quote:
Originally Posted by Peter Nuss
Ok, now I understand a little better what you are asking. No, nutter will not make a tremendous difference if it's running to your satisfaction right now. People that have done the nutter and added the better distributor have noticed a difference. I know I sure did, I would not say a tremendous difference, but, I would not go back either. My main reasons were to remove the 25 year old connectors and replace them with new GM Weather Guard Connectors, inspect/update the wiring, remove items that can cause problems down the road with no benefit now, and to have components they were designed to work together i.e. simple carb, simple ignition system, simple charging system etc. These are simple engines that were burden with stop gap measures to make them meet smog laws. Sometimes not too effciently. I very pleased with the way it runs now, and not so much before.
I did the team rush weekend before last. It was nice, but it still sputtered. I than did the carb swap and it was like a new engine. I'm happy thus far with the result. I didn't nutter, because of the above mentioned reasons, but I suppose I will to see if it makes it that much (or even a little) better.

I want the engine to run at it's max efficiency and performance. I know it's not a sports car, but I want smooth acceleration and no "poppin'-n-snappin'" at higher rpm. I was curious about the downside to nuttering, if there were no issues right now with it. Or, what those issues COULD be down the road from doing it or not

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Unread 06-23-2011, 08:02 PM   #17
monkeyhouse
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Quote:
Originally Posted by jhumphrey View Post
I did the team rush weekend before last. It was nice, but it still sputtered. I than did the carb swap and it was like a new engine. I'm happy thus far with the result. I didn't nutter, because of the above mentioned reasons, but I suppose I will to see if it makes it that much (or even a little) better.

I want the engine to run at it's max efficiency and performance. I know it's not a sports car, but I want smooth acceleration and no "poppin'-n-snappin'" at higher rpm. I was curious about the downside to nuttering, if there were no issues right now with it. Or, what those issues COULD be down the road from doing it or not
Maybe someone else can add more, but I have never really heard anyone complain about problems after doing the nutter bypass. Other than of course the obvious, trouble passing emissions testing.
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Unread 06-24-2011, 07:29 AM   #18
jhumphrey
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Quote:
Originally Posted by monkeyhouse View Post
Maybe someone else can add more, but I have never really heard anyone complain about problems after doing the nutter bypass. Other than of course the obvious, trouble passing emissions testing.
My mechanic buddy told me that the computer would control the timing and that having the timing having the ability to fluctuate was important. He said cutting it out and setting the timing to a certain degree (in this case, 8*TDC) could cause problems.

Honestly, never heard of that before. Not that he's wrong or right, but maybe he doesnt understand jeep's that well... I dont know. I plan to do the nutter and be done with it
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Unread 06-24-2011, 08:08 AM   #19
mcmud
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Your mechanic buddy is spot on in that the micro computer would control timing and I'll add with regard to retard as well as advance. I say would since having removed one of the most important being the BBD, of the 11 total components in that loop of input and to output signals. As it is now the computer is stuck in open loop in the start up or possibly the warm up phase.

And in regard to your buddy saying the computer was important, again he is spot on, it was, just as long as all of those components were functioning as intended. The so called 'team rush' Ford big cap upgrade had zero effect on the computers function but the carb change did.

Do the bypass.
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Unread 06-24-2011, 09:13 AM   #20
jhumphrey
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Quote:
Originally Posted by mcmud View Post
Your mechanic buddy is spot on in that the micro computer would control timing and I'll add with regard to retard as well as advance. I say would since having removed one of the most important being the BBD, of the 11 total components in that loop of input and to output signals. As it is now the computer is stuck in open loop in the start up or possibly the warm up phase.

And in regard to your buddy saying the computer was important, again he is spot on, it was, just as long as all of those components were functioning as intended. The so called 'team rush' Ford big cap upgrade had zero effect on the computers function but the carb change did.

Do the bypass.
Given the age of the YJ, I doubt it was working like it was supposed to. I found vacuum lines that had been eliminated (just hanging loose) and others that were capped. Im sure all that totaled up to performance robbing. Since Ive Team Rushed and done the MC swap, Ive noticed gains in power and throttle response (not to mention better idling and better RPM range). I havent tested the MPG because of all the idling Ive done while working on it, it wouldnt be fair to assess that right now, but my guess is it'll be slightly better.

I discovered my clutch master cylinder had a small leak, so Im changing that this weekend and doing the nutter to. She'll be like a whole new jeep
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Unread 06-24-2011, 06:40 PM   #21
jhumphrey
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Ok, I want to make sure I have the nutter steps:

1) trace orange & purple wires from distributor up firewall
2) cut wires a few inches from firewall
3) find orange and purple wires at icm
4) cut orange wire at icm; splice into purple icm wire
5) connect orange wire from distributor to orange icm wire
6) splice (not cut) purple distributor wire into purple icm
7) time distributor to 8* TDC

Did I miss anything?
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Unread 06-24-2011, 06:57 PM   #22
monkeyhouse
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Quote:
Originally Posted by jhumphrey View Post
Ok, I want to make sure I have the nutter steps:

1) trace orange & purple wires from distributor up firewall
2) cut wires a few inches from firewall
3) find orange and purple wires at icm
4) cut orange wire at icm; splice into purple icm wire
5) connect orange wire from distributor to orange icm wire
6) splice (not cut) purple distributor wire into purple icm
7) time distributor to 8* TDC

Did I miss anything?
you are making it way to complicated. You do need to trace the wires, just to make sure they don't change colors anywhere. All you are doing is cutting the wires coming from the distributor and the wires coming from the icm and taking two pieces of wire and connecting those wires. Most people have orange and purple at both ends, a few do not.
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Unread 06-24-2011, 07:12 PM   #23
jhumphrey
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Quote:
Originally Posted by monkeyhouse

you are making it way to complicated. You do need to trace the wires, just to make sure they don't change colors anywhere. All you are doing is cutting the wires coming from the distributor and the wires coming from the icm and taking two pieces of wire and connecting those wires. Most people have orange and purple at both ends, a few do not.
Thats sorta what I said

I saw two different write ups. One says to cut the purple icm wire, another says to splice the purple wire. I just wasn't sure which was (or if both were) right. I'm going to attach the wires near the firewall to keep things tidy.
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Unread 06-24-2011, 07:44 PM   #24
monkeyhouse
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Originally Posted by jhumphrey View Post
Thats sorta what I said

I saw two different write ups. One says to cut the purple icm wire, another says to splice the purple wire. I just wasn't sure which was (or if both were) right. I'm going to attach the wires near the firewall to keep things tidy.
Sorry, but your use of splice and cut actually confused me, I actually had to go look at my setup to make sure I remembered correctly what I did, lol.
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Unread 06-24-2011, 07:47 PM   #25
dancytron
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Cut the wires. Don't splice in.

My 1990 was orange and purple on each end. I didn't follow them, if it is the twisted pair, you know you have the right ones.
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Unread 06-24-2011, 08:00 PM   #26
monkeyhouse
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Originally Posted by dancytron View Post
Cut the wires. Don't splice in.

My 1990 was orange and purple on each end. I didn't follow them, if it is the twisted pair, you know you have the right ones.
you might wanna do some more research. Basically you got lucky. There is a reason they said to follow the wires through the loom. Carelessness is never gonna be the best policy, especially with vehicles with several owners over 20 or so years.
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Unread 06-24-2011, 08:05 PM   #27
dancytron
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I've opened up the loom since then. There is only one set of twisted wires. Even without the color coding, you can tell which are which from where they originate from.

There isn't any reason to open up the loom if you don't want to, unless you aren't sure what you are looking at.
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Unread 06-24-2011, 08:19 PM   #28
superj
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i just cut mine also. i didn't see any other colors like that and since everything was exactly laid out like the write up said it would be, i just cut it.
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Unread 06-24-2011, 09:03 PM   #29
jhumphrey
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Quote:
Originally Posted by monkeyhouse

you might wanna do some more research. Basically you got lucky. There is a reason they said to follow the wires through the loom. Carelessness is never gonna be the best policy, especially with vehicles with several owners over 20 or so years.
I think in some yj's the wires can change from orange and purple to another color (green comes to mind for some reason).

Thanks all for clearing up that you cut the purple icm wire instead of splice. I figured It made more sense to cut it, but I've never done this before

I'm going to use weather resistant butt connectors and heat shrink to tidy up and connect the wires.
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Unread 06-24-2011, 09:05 PM   #30
monkeyhouse
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Quote:
Originally Posted by jhumphrey View Post
I think in some yj's the wires can change from orange and purple to another color (green comes to mind for some reason).

Thanks all for clearing up that you cut the purple icm wire instead of splice. I figured It made more sense to cut it, but I've never done this before

I'm going to use weather resistant butt connectors and heat shrink to tidy up and connect the wires.
it will be fine, post back if you have any questions.
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