does the EGR help hot starting?

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ebbtide176

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i had some problems getting my jeep running decently. i posted on this late summer. i didn't get back to it until a couple of weeks ago, and don't get much time on it. but it had problems idling when i got it. seemed rich. old 77 CJ7 304 2bbl. <br /><br />i worked on the mechanical issues first, thinking this issue wouldn't be a hard fix. wrong. anyway i got it going. the carb is a new(rebuilt) unit out of the box. 2150 MCraft. i ended up replacing most of the ignition, pulling vacuum lines, disabling emissions, capping off air pump lines on exhst.<br /><br />resolved most of the sputter on throttle with advancing timing to upper limit(bdc). now its drivable, but is still alittle hard to start when hot. i wondered if/how much the EGR helps with this. i have it plugged off with hvy duty foil, along with the exhst manifold/air pump fittings. <br /><br />just curious on my next step. i got the choke working well on cold starts, staying open when hot, but curious on whether the EGR might give the intake enough extra richness to help when starting hot... i have not put the new EGR on yet. or used the carb rebuild kit.<br /><br />oh, yeah - it previously had some wrong vacuum conctns on the breather and all over. comp=good, timing it at top of range, distrb is new(rebuilt), motor seems solid, just this problem idling/cranking when hot. it advances timing on throttle. earlier it would not fire up when hot, but the closed off vacuum lines seemed to help, and keeping it running on hard start was resolved with timing advance. now it will start hot, but requires pumping throttle. alot.
 
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DJ

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Re: does the EGR help hot starting?

Actually, an EGR leans out the mixture.<br /><br />If it cranks over slow, I would be looking at timing.
 
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ebbtide176

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Re: does the EGR help hot starting?

no problem turning over sir dj. it turns over just fine, just not firing up consistantly when hot. but its alot better than earlier. and sometimes is dies just on throttle after idling in gear. i've idled it up alittle to help compensate. thanx for that tidbit though. i can see the logic now, adding extra input to the intake while avoiding coming thru the carb. i'll keep tinkering with it. :)
 
bubbakat

bubbakat

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Re: does the EGR help hot starting?

Ebb I have a mechanics bible it is a shop repair manuel that jeep put out and if I can find it I will post my e-mail addy in here and will give you the info you need to trace this down. I use to fool around with those things for a long time and got tired of the sk-int knuckles so quit. <br />Your problem sounds like it is starving for fuel like vapor lock you know fuel boiling in the lines or hole in the diaphragm or bad or air in the line.<br /> Just a thought
 
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Skinnywater

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Re: does the EGR help hot starting?

And/or one or several vacuum leaks.<br /><br />Sounds like a real mess ebb.<br />A case of beer and the neighborhood shadetree might be money well spent..........seriously.
 
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ebbtide176

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Re: does the EGR help hot starting?

lmao<br />skinny, you just don't know. i would love to have a neighborhood shadeyman, the derwood of jeeps. <br /><br />but not here. i'm stuck with it, and too tight to pay someone else. i guess i've gotta work it out, one way or another. at least the wifie ain't making fun of the 'dead jeep daddy bought' anymore :D my pop is feeling like i do, 'we need to get another shot at that thing, something ain't right'. this motor is by all means solid (to me). good compression, no leaks(ether), just being a huge PITA... i guess everyone deserves this kind of deal to keep the edge. <br /><br />i would be a terd and just drive it to the next TN get-together and throw it out for you guys, but it ain't happening. :) i think its just meant to be. my frickin nemesis is what it is :mad: <br /><br />(amended) i will go over any possible vacuum leaks again. it does have a couple i haven't bothered with- the airline for xfercase to the glovebox, and the tranny line... thanx
 
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ebbtide176

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Re: does the EGR help hot starting?

-just an update ;) <br />i hope i don't have to eat my words, but it seems the jeep is doing ok now. i adjusted the main jets once more after getting the timing problem resolved, and its not cutting out anymore.<br /><br />i took it up a huge steep hill yesterday with no problems. had to go in lowrange with lock just to be safe, but it crawled right up with no hesitation. yehaa<br /><br />i might have to study the vapor lock idea, as someone ran rubber fuel line, bypassing stock lines, and it has dual exhst out sides, which might be heating up the fuel line? hmmmm
 
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petryshyn

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Re: does the EGR help hot starting?

ebb<br /><br />
i ended up replacing most of the ignition, pulling vacuum lines, disabling emissions, capping off air pump lines on exhst.<br />
Click to expand...
If you by chance blocked off the PCV line, it will run rich. <br />Blocked EGR will have no adverse effect except detonation (which will force you to retard timing and reduce efficiency) and possible overheating. . . :(
 
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Trent

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Re: does the EGR help hot starting?

Hey Schematic......Glad to see your still around! Long time no see (or read)! :)
 
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petryshyn

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Re: does the EGR help hot starting?

hi Trent<br /><br />been so busy...nice to drop in now and then.<br /><br />take care! :)
 
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ebbtide176

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Re: does the EGR help hot starting?

thanx for the info schematic! i also replaced the pcv (wrong inlet size on old one) :D i got desperate, replacing stuff, since my noggin wasn't solving the prob, my hands stayed busy :rolleyes: <br /><br />its doing better & better. i will keep that in mind when i start unplugging all the things i plugged off. <br /><br />now that i've brought up the jeep - no, i'll post a new topic :)
 
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petryshyn

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Re: does the EGR help hot starting?

ebb<br />Remember, although they might look the same, PCV valves are internally calibrated for each engine size. Be sure you have the right one or your mixture will be skewed. . . :)
 
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rodbolt

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Re: does the EGR help hot starting?

hello<br /> all that and check your intake manifold vacum at idle. if its lower than about 16 or 17 inces then you may have a leak. if its lower than 14-15 inches and steady you may have late valve timing due to chain wear. its a simple test for timing chain wear that only requires removal of the cap and marking the rotor. there is a whole list of readings for a vacum gauge. its one of the handiest tools in the box.<br /><br /> good luck and keep posting
 
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ebbtide176

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Re: does the EGR help hot starting?

i did not know that about the pcv. but the one i bought is supposed to match this eng, and it was diff than the old one.<br /><br />i am wanting to get a good vacuum pumpkit. i spent the dinero on a better timing light already, so its still on my list. thanx for the info! hmm, i think the other timing light might be a collectible(ebay) :D i could not see the flash on that old light that connctd inline with the plug wire...
 
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