tryin to break in new engine, ruff idle

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If it's not popping back anymore, look down the carb when its running, and you'll notice that drip, and the resulting loss of rpm for a few moments after..
 
screeminDemon said:
Compression test is a good idea too. I looked at the rockers today and the only concern I had was #1 exhaust seemed too loose. I figured it may be a compressed lifter that will fill when the engine runs.

My second concern: the elec choke slowly opens the main carb intake flap fully after a few minutes running. This may sound like a dumb question, but could that be causing a too lean condition, if its fully open?
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Yes like dodge freak said,compression test is in order.

I am concerned about number exhaust being loose and once again I agree with dodge freak on seeing if the rockers are moving the same distance down opening.

On the choke opening the flap after a few minutes that is normal and would not be giving you a lean problem.

Is that when your problem begins?
TXDart
 
it just seemed to slowly get worse as it ran, the first minute was great then as it got warmed up started missing here and there, to full operating temp 185-190 it was missing and coughing too often for me to keep it running any longer
 
so I shut it down because I figured it not good to break in a new engine with a rough idle like that

I'm gonna comp test it tomorrow I guess, even though I hate to turn it over so much without starting it... more cam worry, even though its proven pretty forgiving so far
 
screeminDemon said:
Today when I started it up it ran fairly smooth at first, and I was feelin pretty good, then got steadily worse when it heated up. I shut it off after 10 minutes because it was missing and coughing too often.
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That isn't a bad cam, it would not run good at all at any temps. I think i skip the test for right now but yeah what is just about a valve being loose, is it right after you shut the motor down, lifters can bleed down as the motor cools off

It could be a few things even a bad pick up coil in the dist that acts up when it heats up or the carb is too rich, too high of float maybe. When cold the engine likes all the extra fuel.

The bad pick up I heard about but never seen it. A bad spark plug coil can go bad when it heats up also.

You need to scribe a line on the balancer roughly 35 degrees and set the total timing there and forget about it. Just be sure you rev the engine fast enough that the advance is all in, I like wearing gun shooting ear muffs or just ear plugs and watch out for that fan, should be all in by 4,000 rpm hopefully sooner

Holley makes a good carb but they can cause alot of grief when they act up, that be my gut feeling but then it could be spark related.

I had a bad spark plug boot that was torn, only missed when engine was hot, spark was jumping to a header pipe but only when the headers were very hot. Turn it off 20 mins it run fine for 1--2 mins and then sometimes miss only when driven hard unless it was very hot.
 
Why not just cover the choke area up with your hand and see if it helps, if so its too lean. I forget sometimes about the choke since my carbs have none.

If it is the carb--helps as you cover the choke with your hand, I personally would get a Eddy 600 carb and ditch the holley. It be down a bit on power but be more reliable and idle better with less fussing with
 
TXDart said:
Yes like dodge freak said,compression test is in order.

I am concerned about number exhaust being loose and once again I agree with dodge freak on seeing if the rockers are moving the same distance down opening.

On the choke opening the flap after a few minutes that is normal and would not be giving you a lean problem.

Is that when your problem begins?
TXDart
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But what if there was dirt in the jet or passages, as the choke opens the carb then does get leaner. Simple thing is just push the choke flap down a ways if it moves easy, if not use your hand. That be quicker than a compression test. I'm thinking it was just a lifter bleeding down why the one valve seem loose.
 
Try finish breaking that cam in,since you have a timing light set it so it is under your wiper blade with a zip tie holding the trigger and all cables out of the way of header,fan,etc...and pointed to you in the driver seat.
You should be see steady blinking light,if when it start to act up and it is still blink steady,then may not be ignition problem but if it start being erratic you found your problem.
Keep us posted,
TXDart
P.S. Is your orange box attach to the firewall real good, it is grounded to the body thru the bolts that attach it.
 
dodge freak said:
But what if there was dirt in the jet or passages, as the choke opens the carb then does get leaner. Simple thing is just push the choke flap down a ways if it moves easy, if not use your hand. That be quicker than a compression test. I'm thinking it was just a lifter bleeding down why the one valve seem loose.
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Or he could adjust the choke to stay almost shut all the time until he got that cam broke in.If that is his problem,who knows but I hope he figures it out.
TXDart
 
Thanks so much for stayin with me dodgefreak and txdart! I really really value your advice. Bein that its 4th of July today, I am planning for 1 hr only working on my car. The rest of the day and eve, I need to spend with my family, even though my mopar beckons.

I'm gonna try a couple of your suggestions: will run motor with timing light facing my windshield so I can see it and my tach at the same time. Will finish breaking in the cam (I've already got about 15 min run time on it, so I'll do 15 more). Will try holding carb closed off instead of letting the choke turn the flap completely vertical.

PS - I've already ordered the holley rebuild kit from summit, but probly wont get it until wed.

Will keep you posted with the results. Thanks thanks thanks!
 
PS - Yes I have the orange box screwed to firewall after scraping off the paint to make good contact.

Also - Both Inertia and Dodgefreak have gut feeling its the carb. I'm getting the same feeling too now. I did some research on it: its a 4180 model made for motorcraft (ford) in the early 80's mustangs. It is known as an "emissions" carb.
 
Probably got the numbers mixed up, if it's an 1850, that's a 600, and they work fine, when they're adjusted properly. But a little small, and could be up-graded later..
 
I got a holley kit and rebuilt the carb. $ is short so I didnt want to buy a new carb. However I still have the same problem. I got the float levels adjusted using the bowl windows and transfer slots adjusted. The only way I can get it to run smooth and stop popping is by holding the choke closed by hand while its running.

So it must be idling too lean. I've got the mixture screws 1.5 turns out. I'm scratching my head again. Any ideas are appreciated. Thank-you!
 

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The jets could be too small. You say its for a newer car :cry:

That is a great sign the motor runs better with the choke on. Its your carb, thats for sure. I would jet it up, if you got wire drills, ope the jets up .005, even .010.

I got a feeling those jets are special and harder to get. If anybody has them it be Summit Racing. The problem is the idle bleeds might be too small also, why best to get different carb. Even a holley but not emissions type.

Yep, dirt cheap me would just carefully drill the jets a bit larger, no point putting money in to a half *** anything. Needs a good old 750 vacuum secondary holley
 
The fuel lines and tank are clean, but thanks for your input Green1.
DodgeFreak I'm glad you agree wth me its a carb issue. I'm seriously considering getting a new carb now, even though I just blew 50 bucks rebuilding this Holley 600.

But I'm also worried about my big cam and Edelbrock Torker II manifold. I read this today on another website "Very good for high-rpm use, these manifolds can be a real challenge to tune for low-end, street rpm
use. A single plane manifold will typically significantly reduce vacuum, and this causes several problems."

The website mentioned low vacuum and difficulty tuning the idle transition. I cant even get my engine to idle without turning in the idle speed screw to get it above 1800 rpms and partly choking the carb. Then I see fuel dripping into the carb from the mains. It seems the idle circuit isnt even working, because the mixture screws dont do anything. I thnk I'm getting it to idle using the mains. I think it lacks the vacuum to pull from the idle circuit. But I've triple checked for vacuum leaks.

I'm thinking of getting a new carb and intake. It hurts to dump hundreds more into it, but I need it running. Whaddya think?​
 
That Holley is calibrated too lean for your cam size.Beg or borrow a early Holley or Ebrock,and break in your cam.I had one of these Ford/Holleys with the Melling 204/214 at .050 cam in a stock 302.It would smog,but I had to put 600 double pumper just to get it to run decent.You can tune em,parts are rare and pricey.Good luck,man.
 
Yeah that intake is for high stall, 4.10 gear cars and its not thought of as one the best eddy intakes. It is low profile, a big draw for those with limited hood space.

I still think you could get it to idle fairly well--if the intake isn't leaking. Its too lean, just why. Its unlikely but if tighten too tight you can split the intake gasket.

You sitting down, lol, different carb, different intake..ebay or fabo sell both, get IMO a older eddy intake or those rpm, the new performers intakes aren't so great...and carb, like others said, an older holley or Carter

Bucks down, just try different carb, still isn't night and day difference then pull the intake and check for a bad gasket--unlikely but would cause a big vacuum leak..

I recall long ago, had nothing to do, thought I check my intake bolts to see if they are all tight, how I split the gasket and found out first hand. I now use only steel core intake gaskets, fel pro makes them around $40, i know, stuff is overprice..I drill a small hole for the intake exhaust heat on each side. I believe in warm intakes. That intake you have now has exhaust heat ports, I hope they are open, only in hot weather--90 plus--you don't want intake heat, IMO
 
Lean lean,itssssssssssssss to lean.Try this start it up when it starts to run rough por a bit of fuel down the carb,choke wide open I bet it will smooth out.
 
Your right snake, because I've already tried what your talking about (but sprayed starter fluid instead) and it improved.

DodgeFreak, as much as it pains me to open my wallet again, I think your right, and I need to get rid of the Torker manifold and the carb. It turns out that just about everything this guy gave me turned out to be crap. I thought I had scored with the Eddy alloy intake and Holley 600 that he threw in with the block. He also gave me a water pump (that leaked at first startup) an alternator (that was single field instead of dual) and a couple of old 2 bbl carbs. I think he just cleaned the sht out of his garage that he didnt want.

I have a stock 360 cam in perfect condition. Do you think I should swap it out when swapping the intake, and save the summit 1798 cam for my next motor (which I already have the block cleaned and punched 30 over)?

Again the summit thats in it now: 284 advertised duration, 480 lift.

Thanks again for all your advice!
 
I think it wouldn't hurt to degree the cam, too. The "dot to dot" method is pretty inaccurate to setup a new engine with. I have seen timing sets off as far as 15 degrees.
 
I would not open the engine up just yet, if you get the carb problem worked out then drive it and see if your happy. The motor should idle ok, its still a street intake. Heck the 273 first came out with a single plane intake.

I know of some engine tuners who claim single plane intakes are the only way to go. Fuel distribution is more even between cylinders
 
I agree, I need to marinate on this a couple days before I take anything apart or make any more purchases. I think I'm gonna do a compression test too.

I just dont know why it wont idle without choking it and keeping it at 1800rpm. Its possible I made a mistake rebuilding the carb, its my first one, but it didnt seem that difficult.

The cam is not that radical, really. I know its too big for stock pistons, but still...

PS - I don't know anything about adjusting cam timing other than matching up the dots like I did when I built it.
 
Big torker , big cam , small carb , heads and pistons , you have a bunch of mismatched parts . If you get it running it will most likely have no bottom end , top end will be limited by carb . I had a torker years ago and it bogged below 2500 then it let loose but died out at 5200 , not enough cam or heads, changed it over to a ld 340 and car improved big time . More power from 1200 rpm up , car was a lot more fun to drive .
Best get a new carb and intake , it will run really well . Carb is probably your immediate problem , not rebuilt properly . After that should go well
 
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