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Unread 12-14-2011, 08:03 PM   #31
Old4X
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1990 CJ7 
 
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Get a good, strong flashlight and put your reading glasses on. It should be obvious how it comes apart.

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Unread 12-15-2011, 09:36 AM   #32
JeepJon15
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Okay, after you said the piece just pops off it was simple. Thanks a lot.

So i replaced the body flange gasket (bottom), the bowl cover gasket (middle), and the dust cover gasket on the top just because that one was easy to get to. I also replaced a couple pieces of bad hose. The bottom gasket looked a little worn, i'm not sure if it ripped when i pulled it off or if it already had rips but it was broken in a coupple spots. The other gaskets looked okay so i replaced them but saved the old ones for later use maybe?

Took out venturi cluster and cleaned the idle tubes. All went well and i got it put back together. Right now i've got it running okay, but i think i need to refer to your tuning instructions earlier in the thread. Its acting like the throttle is sticking just slightly, but i'm thinking maybe the mixture screws need reset and it needs re timed (car is at operating temp). I'll report back when i have it tuned the best i can.
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Unread 12-15-2011, 10:06 AM   #33
JeepJon15
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Everything seemed good... I went out to tune it. Turned idle screws in, then out 1.5 rotations. Went to start it, nothing. I backed them out some more, evenly. Still just turning with no combustion. It seems like its not even getting spark anymore. What on earth could i have done. It was running 15 minutes ago, this is the first time since i replaced the ignition module with the HEI gm module that i havent been able to get it to start at all. The ignition coil is only a week or two old. Up untill now the HEI module has been flawless, and before it went in, i had no spark.

The jeep should still be up to operating temp.

I'll be tinkering until work in a couple hours. This is a bit disheartening, any advise? Just when things were improving hah...

Thanks, Jon.
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Unread 12-15-2011, 10:42 AM   #34
oldtime_ironman
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Quote:
Originally Posted by JeepJon15 View Post
Everything seemed good... I went out to tune it. Turned idle screws in, then out 1.5 rotations. Went to start it, nothing. I backed them out some more, evenly. Still just turning with no combustion. It seems like its not even getting spark anymore. What on earth could i have done. It was running 15 minutes ago, this is the first time since i replaced the ignition module with the HEI gm module that i havent been able to get it to start at all. The ignition coil is only a week or two old. Up untill now the HEI module has been flawless, and before it went in, i had no spark.

The jeep should still be up to operating temp.

I'll be tinkering until work in a couple hours. This is a bit disheartening, any advise? Just when things were improving hah...

Thanks, Jon.
Do you have spark now? test for that. Good job on the carb and gaskets BTW!
.
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Unread 12-15-2011, 11:02 AM   #35
JeepJon15
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Thanks! It has been a good learning experience. I have spark now, i decided to try my old ignition coil, no change with that. I then went back to the new one and she fired up. I let it warm up to operating temp and checked the timing. It was at about TDC (maybe i tried setting the timing before it was all the way warm before), no advance at all so i put it back to 8 degrees, messed with the mixture screws and got them to where i think is good (havent purchased a vacuum guage yet).

Was it not starting because the timing was so off? I'm still confused, but glad something didnt fry in the ignition module or coil.

It still seems like either the throttle is sticking or the choke is not set correctly. If i lightly tap the gas it will rev up and sometimes slowly go down as usual, but sometimes get stuck at about 1200. Now... when it gets "stuck" the jeep is strong in gear. When its not stuck, the jeep wants to sputter out when i first get into gear, but idles at 750ish.

Now i'm letting it cool down so i can set the choke via Old4x's instructions on the first page. I'll be at work till later tonight, but if anyone has explanations or advice for when i get back that would be a huge help. Thanks a lot guys, i feel like i've made more progress this week than i have in the past few months messing with it on my own.

Side note, i just put new wheels and tires on her, replaced a bad tail light housing, and replaced my missing rear soft top window. Hope to get her back on the road by this weekend!
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Unread 12-15-2011, 11:39 AM   #36
oldtime_ironman
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Good going! Its not unusual for carbs to get gummed up because people neglect them so much. After you get done adjusting the choke, I would hose down all the linkage and shafts real good with a spray can of Gumout - that stuff is magic.Its my old standby.
.
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Unread 12-15-2011, 06:38 PM   #37
JeepJon15
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Okay i'll do that. Will PB blaster work as well as Gumout? Should i not use pb for any reason?

Also, i removed the springs holding the linkage when i was messing with the carb. Is there a chance that when i took them off i stretched them a little and they aren't as tense as they should be now? If so i'm sure i could bend the ends enough to create more tension. It seems like this could cause the linkage to not snap back all the way after it is engaged.
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Unread 12-15-2011, 07:15 PM   #38
oldtime_ironman
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Quote:
Originally Posted by JeepJon15 View Post
Okay i'll do that. Will PB blaster work as well as Gumout? Should i not use pb for any reason?

Also, i removed the springs holding the linkage when i was messing with the carb. Is there a chance that when i took them off i stretched them a little and they aren't as tense as they should be now? If so i'm sure i could bend the ends enough to create more tension. It seems like this could cause the linkage to not snap back all the way after it is engaged.
PB blaster will prolly work, just not as good as gumout when it comes to cleaning. You could tweak the springs I guess, I've done it before. Most all the springs on a carb are designed to be "just right" so if any of them feel slack, I would take them up just a bit.
.
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Unread 12-15-2011, 07:28 PM   #39
JeepJon15
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Makes since to me. I had to do some wiggling to get the at the right angle, so it wouldnt surprise me if i stretched it a hair. I'm gunna go out and do that now.

As far as the engine wanting to stall in gear. Like i said above, when the throttle wasnt sticking a little the engine wanted to stall out when i either shifted into drive/reverse or when i came to an abrupt stop in gear. I'm expecting to hear i still have a vacuum leak to track down, but i dont know where else to check. Any hot spots for leaks i could be overlooking?

Come to think about it i have a hose splicer on my vacuum line that goes to the dist that may be a size to narrow. The hose stays on fine, but its not as tight as it could be. Is there enough vacuum going through here that the narrower opening is effecting performance?
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Unread 12-15-2011, 07:38 PM   #40
oldtime_ironman
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Quote:
Originally Posted by JeepJon15 View Post
Makes since to me. I had to do some wiggling to get the at the right angle, so it wouldnt surprise me if i stretched it a hair. I'm gunna go out and do that now.

As far as the engine wanting to stall in gear. Like i said above, when the throttle wasnt sticking a little the engine wanted to stall out when i either shifted into drive/reverse or when i came to an abrupt stop in gear. I'm expecting to hear i still have a vacuum leak to track down, but i dont know where else to check. Any hot spots for leaks i could be overlooking?

Come to think about it i have a hose splicer on my vacuum line that goes to the dist that may be a size to narrow. The hose stays on fine, but its not as tight as it could be. Is there enough vacuum going through here that the narrower opening is effecting performance?
If you have an auto trans then a vacuum leak will almost always make em stall out. You should get on that pretty quick with that dist line and splice. Use a hose clamp or something to tighten it all up. In fact I would check all your vac lines.
.
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Unread 12-15-2011, 08:39 PM   #41
JeepJon15
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I have checked them and got everything i could find fixed, i'll do a double check... once i get the thing turned back on.

I went out and pb blasted the linkage and bent the springs to give it more tension. I go to start it (hasn't been started since before i left for work around noon) and *crank crank crank clickclickclickclick*. I left it in the garage while i was gone, so i didnt take the keys out of the ignition. There is a chance i left the battery on or something, i dont know. So i push it out and jump it and i still cant get it started. It cranks and if i pump the gas just right i can get it to chug, but what the hell? haha

I didnt do anything but grease the linkage since i had it running last and now this. The HEI module is wired correctly, the purple and orange are twisted, connections are all good. I have basically oem style wires, dist, plugs, coil everything but the module basically. Its not all brand new, but everything but the wires have been replaced within the past 8 months.

I'm probably not going to do anything else on it tonight... I'm pooped. But i will be hanging around on here to see if anyone has advice. I'll have the weekend to work on it.

Thanks a lot... for talking me through this roller coaster.
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Unread 12-15-2011, 08:39 PM   #42
Old4X
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You may need to bump the idle up a bit for the auto tranny. Manual tranny setups can get by with lower curb idle. (and the figure I quoted was for a manual).

What does the sticker under the hood say for idle speed?
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Unread 12-15-2011, 08:41 PM   #43
Old4X
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Stick a battery charger on it overnight and go for a ride in the morning.
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Unread 12-15-2011, 08:48 PM   #44
oldtime_ironman
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Quote:
Originally Posted by Old4X View Post
You may need to bump the idle up a bit for the auto tranny. Manual tranny setups can get by with lower curb idle. (and the figure I quoted was for a manual).

What does the sticker under the hood say for idle speed?
yeah, I had forgotten about that... Most of the auto trans I've seen, tell you to set the idle speed while its in drive with the wheels locked or blocked.
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Unread 12-15-2011, 09:18 PM   #45
Old4X
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On your HEI install. I was having some problems with the condenser. The mod instructions said it was optional, so I removed it from the mod. No problems since.
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