tryin to break in new engine, ruff idle

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even if a lobe was gone the base circle should not have changed, correct?

did you roll those pushrods, sometimes they bend if the timing chain jumped. I would pull that shaft off and compare the push rods for length.

I know some of my rockers get loose when the engine is off and yeah they are hyd.
 
dodge freak said:
even if a lobe was gone the base circle should not have changed, correct?
Click to expand...

Thank-you! because I thought of that too. I'm checking these rockers without lifter on lobe.

I removed the rocker shaft already and checked the lengths of a couple of pushrods and they all the same, and not bent.

It seems, by process of elimination, the only thing it could be is slightly bent or worn rocker shaft or the rockers themselves. It just seems so weird, I figured there must be something I'm missing here.

But the original motor was well worn, with a spun bearing, and the rockers are about the only thing that haven't been rebuilt or replaced. I just cleaned them.
 
screeminDemon said:
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."​
Click to expand...

I didn't put the huge cam my 340 has so I cannot say what it is but the thing idles like a full out racer. The car has a torker 340 and probably a 750 size double pumper with no choke. The engine doesn't come on till 2500 RPM but will idle just fine at 900. If I don't start it by stomping on the gas 6 times before firing it the carb will backfire and has flamed before.

You have any plug wires touching each other and letting them crossfire? Are you using premium gas (hopefully without jokenol)?
 
It doesn't make sense for those two to be loose if all the pushrods are the same. I would start the engine and then check right after you shut it off...I know the lifters got that little spring inside, still I know for sure a few rockers of mine get loose an 1/8 of an inch but they tighten right up with oil pressure.
 
Found the problem with the 2 loose rockers!

I pulled the rocker assembly off again and laid an 18" metal ruler across the tops of all the valve stems, and sure enough there's 2 valves that were 1/8" short of hitting the ruler - the same 2 that had the loose rockers. I tried that before, but I must have done it quickly and carelessly not to have noticed.

So 2 of my stainless valves are a different length (a little shorter)? Do they make em different lengths? Here I am scratching my head again. Startin to lose my hair. I guess I'll try calling the machine shop and see if they remember my heads. Maybe since they knew I was planning to use adjustable roller rockers, they figured it didn't matter if they put in different size valves... I don't know.

But it should be fixed with using my roller rockers right? thanks for your advice again
 
i should have read all the post so if im jumping in and the wrong spot scold me. when you put a cam in with higher lift the base circle of the cam gets smaller dropping the lifter deeper in the bore this makes it have to pump up more the normal and that with a valve not sticking as high as stock(due to new seat or the valve being tipped) there may not be enough lifter there to make up the gap.at this point an adjustable rocker might fix it but probably the better way is to put a long push rod on the engine or maybe both
 
Well at this point I guess I would just go ahead and put the adjustables in seeing as you have them and don't have to buy them, then you can back at it. I had a .475 lift in my old motor and the oem rockers chattered bad so I had to put in a set of adjustables, at that time 1983, I didn't even think of getting longer pushrods..good luck keep us informed
 
Well yeah, I'm just trying to get this guy problems solved easy and quickly as possible. Really heads should be pulled and see whats up on the valve job, hopefully the valves are too short and the other valves are not sunk in too deep due to too many valve jobs.

Did you ever do a compression check ? I'm even wondering if the valves are all sealing tightly, if not that could cause rough running
 
Still having problems? I have had many holleys have this problem and most times it turns out to be clogged idle air bleeds. Looking down into the carb., they are the larger bleeds towards the outside of the carb. Take your time and flush these out real good. Make sure you get all the crud out and not just move it around. The larger bleeds actually suck in more dirt than you would think. I've seen this cause all kinds of issues from a rough and rich idle to uncontrollable carb siphoning in a non vented system. I've built many dirt track engines and this was a commom problem that many people in the pits would miss. 1 can of carb cleaner and a air hose and I was a life saver. Just my 2 cents worth!!! Good luck and let us know how you make out.

Rick
 
thanks for your input fellas!

a couple things: spark plug wires are new and I have em well spaced
Holley carb idle bleed stuff: Yes, I'm hoping that was my problem, I'm currently awaiting delivery of a TQ rebuilt by DemonSizzler

While waiting, I decided to remove Eddy 340 Torker manifold and put Eddy Performer on to better suit my engine.

The heads: Yes, I'm with you DodgeFreak, I'm concerned about the heads now too. But I have to remember it ran pretty smooth when I smotherd the carb temporarily. No I never did a compression test because I was worried about wearing the cam too much, since motor was only run for about 30 min (in 3 sets of 10 min) and I didnt want to wreck anything more. In hindsight, I wish I had done the comp test.
 
Well maybe its OK, even those 2 valves you think are too loose. That little spring in the lifters don't seem to do so much to keep the pushrods tight, its oil pressure that holds them firm.

I guess if you have everything and since the intake is off, go ahead and at least that side put the adjustable rockers on. You can see the cam, pull the spark plugs so the engine turns over easy. If you got the time do both sides. You got to pull all the plugs, least i would. You want each lifter close to the middle of the base circle when you adjust that pushrod

Heck once its running again, run it for 15--20 mins at 2,500 rpm. I like using a garden hose and keep spraying the rad down with water to cool it off. Then change the oil and filter and you should be done.

Too bad fuel cost so much and its getting to get worst yet with 55 mpg cars for 2025. One gallon of fuel going to be $10 I'm afraid.
 
Maybe that cylinder had bad valve guides/seals and allowed more oil to leak in and help to lessen wear on the seats ? i don't know, just guessing, maybe some other guy did the last cylinder and didn't grind as deep ?

Maybe they forgot to do that last one ? maybe you got new valves on old seats--not likely but maybe they did forget to do that one cylinder ?

You know you still can do a compression test with a cold engine. The lifters should be full of oil so I would pull all the plugs out and spin the engine over with the starter till there is some oil pressure. You can pour some motor oil over the cam and lifters so the cam doesn't wear.

Once there is oil pressure then start the compression test.

I got this feeling it was just a very lean carb and your worrying about 2 rockers needlessly. after 2 weeks of sitting I can move a few rockers an 1/8 of an inch if I really try. been thought it adjusting those rockers with the intake on.
 
Are you absolutely sure you don't have a vacuum leak?

When you had the intake off did you visually inspect the cam lobes? Especially those 2 with different lash?
 
Thanks for stayin with me dodgefreak, you don't know how much I appreciate it. Ultimately I think your right and the 2 loose rockers are not that big of a deal, probably just wasnt getting the full lift on those 2 exhaust valves... maybe something like a stock cam would give or a little less maybe.

I'm gonna put the roller rockers on tomorrow. I like your suggestion of doing a comp test but theres multiple lifters that have bled down now, so I dont think its worth it right now. The heads looked like new when I got em back from the shop, so I'm gonna stay positive and believe they're sealing good.

I just gotta get this thing bolted back together, get a good carb on it, and run it another 20-30 minutes like you said. Will keep you posted!
 
RPAGAN said:
Still having problems? I have had many holleys have this problem and most times it turns out to be clogged idle air bleeds.

Rick
Click to expand...

This is what I believe (hoping) is the problem.

But to answer your question C130Chief - I did inspect the lobes and they all look great. Your other question about the vacuum leak. I'm not a pro, so I cant be positive, but I think I did a pretty good job checking for any possible vac leak. I was also told my .480 lift/ 284 advertised duration cam combined with the Torker manifold = very low vacuum.
 
When you spin the engine over with no spark plugs it turn really fast and build up oil pressure so the lifters that bled down will be full of oil once again.
 
A couple of things I noticed as I went through this thread:
1) Are your new wires copper? That is a no-no with a lot of electronic ignitions.
2) Is your fuel pump old. Older pump diaphragms are not meant for the new crap gas and disintegrate. You may be getting crap in your filter and impeding fuel flow.
3) Have you checked the coil? A lot of times coils will act up only after they are hot.
4) Gap on your dizzy .008?
5) Plugs gapped at .045? Electronic ignitions usually like a wider gap than normal.
 
harvenator said:
A couple of things I noticed as I went through this thread:
1) Are your new wires copper? That is a no-no with a lot of electronic ignitions.
2) Is your fuel pump old. Older pump diaphragms are not meant for the new crap gas and disintegrate. You may be getting crap in your filter and impeding fuel flow.
3) Have you checked the coil? A lot of times coils will act up only after they are hot.
4) Gap on your dizzy .008?
5) Plugs gapped at .045? Electronic ignitions usually like a wider gap than normal.
Click to expand...

Thanks for your input harvenator.
1) My plug wires are new 8mm Accel from autozone. I still have the box so I'll check if they're copper, cuz I don't really know.
2) I'm running a clear fuel filter and it still looks clean. Fuel pressure has been good.
3) Coil is new Accel (higher voltage output than stock I thnk)
4) spent alot of time getting dizzy gapped exactly at .008.
5) I gapped at .035 like my manual said. You think I should go .045?

PS - I still cant ignore how much the motor smoothed out when I choked it manually.
 
I would bump the gap up to .045. You can always coose it up incrementally if necessary. All the new electronic cars call for a wider gap. Allows the coil to build more voltage to jump the air gap. When you choke the motor you are actually enrichening the fuel mix. How have the plugs been looking?
I believe that in one of your earlier replies you had checked for leaks. Did you spray around the carb base and the intake with WD-40 or brake cleaner or even water ?
 
If choking the engine manually smoothed it out, you are lean. I know it sounds like beating the crap out of the obvious, but make sure a vacuum connections on the carb are capped, you have correct base gasket etc...
 
I run .030 plug gap and I got a MSD 7al box and hvc coil. The way I see it is the smaller gap takes less voltage to fire. Yeah I might be losing out on 5 hp, oh well.

Opening the gap from .035 to .045 will do nothing to make the engine run smoother
 
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