News:

It appears that the upgrade forces a login and many, many of you have forgotten your passwords and didn't set up any reminders. Contact me directly through helpmelogin@dodgecharger.com and I'll help sort it out.

Main Menu

my new 360 wont idle

Started by nrt69, July 06, 2011, 09:26:29 PM

Previous topic - Next topic

nrt69

i got my new 360 to fire up but i cant get it to idle for nothing. ive adjusted the timing back and forth and completely cleaned and rebuilt the carb.

any suggestions?

b5blue

What carb.? Ignition and dizzy? Type of choke? Ignition first then carb. Base line throttle linkage settings as you may be into secondary's, check for vacuum leaks, A/F mix too lean?  :scratchchin:

nrt69

eddy 650 cfm, manul choke, fuel mix and idle screws set up per eddy instructions.
mopar performance electronic conversion with about 90k miles on it (it worked fine with my old motor)

y3chargerrt

Are you monitoring your vacuum as you tune?

Steve P.

9 out of 10 times I find a vacuum leak causing the issue. Monitoring timing and vacuum are essential. I would start with pulling and plugging all vacuum hoses at the carb and base. Fire it up and see what you've got. If it still won't idle, use a light spray of carb cleaner around the base of the carb first. Try to be specific where you aim as it will point out where the the problem is if in fact it's a leak.
Steve P.
Holiday, Florida

nrt69

what do you mean by monitor vacuum? ive plugged all the vacuum ports and it still wont do anything. everyone is telling me timing, but ive rechecked TDC and firing order a billion (not literally) times.
someone said the balancer marks could be wrong?
carb is flush with intake and theres a new gasket under it.
i do have a slight kink in the stock 5/16 metal fuel line that runs to the intake, where it then goes into a filter, then 3/8 hose to the carb. i cant see the slight kink cutting off that much fuel at idle though.

randr

adjustment screws on those carbs or only really for idle. if you turn each side in on at a time does rpm go down? if not one side or other is plugged. or one hell of a vacuum leak
I'm Bored! what to do next......

y3chargerrt

Do you have a timing light and a vacuum gauge to tune it with?

nrt69

yes,rpm will go down turning them in. i have them set at 1.75 turns from bottom. eddy says 1.5-2.0 turns from bottom.

i put a timing light on it tonight (no advance dial). i made some makeshift timing marks on the passenger side since my timing cover marks are under the water pump hose and power steering resovoir. at @1100rpm i estimate im at 20+ degrees BTDC.

i dont have a vacuum gauge. where would i hook one up at?

nrt69

got a vacuum gauge and hooked it up on the intake port behind the carb. engine builder says 9-12hg at idle. im getting 9 at 1100 rpm. it drops to 5hg at 500rpm before it stalls.
i sprayed carb cleaner in/around the carb. decreased rpm.
i sprayed around the intake and might have gotten a slight rpm increase at the corner of the intake closest to the passenger seat. i used rubber gaskets for the intake sides, cork at front/back, and silicone inthe corners.

I guess i need to pull the intake off and check?

nrt69

just tried it again and got an increase in rpm when spraying into the carb.

nrt69

F&$King sh!t this is driving me crazy.

i got it to idle but theres obviously bigger problems.
my idle is 900-1100rpm when the engine is hot, and drops to 500-600rpm in gear. timing is @20degrees BTDC at idle. vacuum is 6-8hg.
engine guy says 14BTDC at 800rpm idle with 9-12hg vacuum. trans guy says it shouldnt drop off that much.

I dont think it the carb and cant find an increase in rpm when spraying carb cleaner around the intake.

the motor will not run with the timing anywhere else.

any suggestions???

Musicman

Setting the idle screws to the starting position is just that, a starting position... Have you actually set the idle circuit up correctly? If not it will can cause all kinds of headaches later on and have you chasing your own tail around.

Ignition first, then the Idle Circuit, then your power valves and jetting...


If you want to try setting the Idle Circuit up correctly, here is the right way to do it....
If you don't have a tach just listen to the engine and play it by ear, but a vacuum gage should be used.

To begin, make sure the engine is up to full operating temperature and the choke is completely off. A cold engine requires more fuel than a fully warmed engine even if the choke is off. Remove the air cleaner and connect the tach to the engine, and the vacuum gauge so it reads manifold vacuum.

Before you fire up the engine, slowly turn each idle-mixture screw in until it gently bottoms out and count the number of turns it takes. Do this for each idle-mixture screw and then return them to their original positions. If all the idle-mixture screws are not adjusted the same, do that now. Remember to always adjust both screws the same amount. This will help balance the idle mixture and allow the engine to run as smoothly as possible. If the carburetor is new to the engine, start at 1½ to 2 turns out (counterclockwise) from full in.

Now start the engine and set the idle speed to around 850 - 900 rpm's or so with the curb idle-speed screw. If your engine has a big cam and must idle at a higher speed, that's OK. Note the reading on the vacuum gauge. Next, very slowly turn one idle-mixture screw in ½-turn and note the change on the vacuum gauge. If the vacuum reading increases say, from 14 inches to 14-½ inches, move around to the other side of the carburetor and slowly turn that mixture screw in ½-turn as well. If the engine stumbles or the vacuum drops when initially turning the mixture screw in, turn both screws out about a ½-turn and evaluate the results. On most carburetors, turning the mixture screw in (clockwise) leans the mixture, while counterclockwise (out) enriches the mixture.

The goal of adjusting the idle-mixture screws is to achieve the highest possible idle vacuum at a set idle speed. If the idle speed increases after you adjust the idle-mixture screws (which is likely), be sure to adjust the curb idle speed screw back to the base speed again before moving forward. This is important because a higher idle speed will increase the vacuum reading. Maintaining a standard idle speed will make it easier to evaluate changes to the idle-mixture screws.

nrt69

am i setting the curb idle speed screw to 900rpm with as many turns as necessary? the idle screw is already turned in quite bit.
and am i doing this with the timing at 20BTDC as it is or 14BTDC as recommended? cause at 14BTDC it wont run.


b5blue

  This is where distributor set up is critical. Ignition is set first and must be right, are you running vacuum advance? Is it adjusted correctly if so? Mechanical advance settings, what are they? Type and condition of  plugs (even gap.), wires, coil and so on. You have to have all that optimized before getting much into the carb. adjustments.   :2thumbs:

y3chargerrt

If your running vacuum advance disconnect it and recheck your timing.

nrt69

Someone tell me where im going wrong cause this problem is driving me crazy:

new 360 engine, 480/280/230 cam, eddy intake and rebuilt eddy carb set to specs.
new 904 trans with 2500 stall, full of fluid.
i set the #1 at TDC and dropped in the distributor gear so the rotor would be pointing at #1.
ive rechecked the wires/firing order 100X.
the distributor is a Mopar Perf electronic conversion with alot of miles on it.
spark plugs at gapped at 35.
Engine wouldnt run below 2000rpm.
i then played with the timing and carb and now its at @20BTDC at 800-1000rpm idle. engine builder says to put it at 14BTDC.
theres only 5-8hg of vacuum at this idle (engine builder says it should have 9-12hg).
all of the vacuum ports are capped or plugged.
ive sprayed carb cleaner around the carb and intake, no significant issues there.
the carb screws are turned in probably too far and its probably running off primary circuit but its idling.
turning the distributor in either direction will cause motor to shake and stall.
I can drive the car as is but theres significant pinging under load because of the timing.

I dont think the timing chain was installed incorrectly (see pic) and if the distributor gear was off slightly i should be able to correct it by rotating the distributor when adjusting the timing right?

FLG

Did you make sure that was tdc on the compression stroke? (Both valves closed)

Rolling_Thunder

is your choke hooked up ?   
1968 Dodge Charger - 6.1L Hemi / 6-speed / 3.55 Sure Grip

2013 Dodge Challenger R/T - 5.7L Hemi / 6-speed / 3.73 Limited Slip

1964 Dodge Polara 500 - 440 / 4-speed / 3.91 Sure Grip

1973 Dodge Challenger Rallye - 340 / A-518 / 3.23 Sure Grip

HPP

Its hard to make out in your picture, but it looks like you have power brakes. Try disconnecting the power brake booster hose and plugging its attaching point on the intake. A vacuum leak in the booster diaphraghm can cause serious idle problems.

Musicman


nrt69

yes, i set it up on the compression stroke at TDC.
choke is not hooked up.
no power brakes...all vacuum sources are capped or plugged.

the only thing i havent tried is different intake gaskets and a new distributor. My neighbor is convinced its a vacuum leak. Can my 20BTDC setting at idle be due to a vacuum leak??
i dont think its the distributor since it worked fine on my old motor.

b5blue

Are you using vacuum advance on the dist.? Seems to me set the timing @ 12-14* THEN hook up vacuum advance and IT will put you back to + or - 20* at idle but drop out and let mechanical advance take over with higher RPM's. Get me? (The engine wants more timing @ idle but not @ off idle until higher RPM's.) Your getting a bigger drop in RPM's then is right when you put it in gear. You may be into the secondary's on your carb idle settings trying to compensate for timing settings or adjustments. The vacuum advance is adjustable to a degree by using an allen wrench inside the vacuum nipple on the dist. to increase or decrease the amount of action.   :scratchchin:

Musicman

Depending on ambient temperatures, if you do not have a fully functional, properly adjusted choke, it will not idle at "low rpm" on startup... you will have to keep your foot in it to keep it running until it warms up. Once the block is up to temp, 900 rpm is fine...

nrt69

im not using vac advance. all vacuum locations are capped.
not using choke either.

I did just find this while researching the used performer intake on put on the motor:
http://www.edelbrock.com/automotive_new/misc/tech_center/install/2000/2176.pdf

edelbrock says I "MUST" "USE ONLY" their intake gaskets and put silicone at front/back. i didnt do that. I used the rubber gaskets on the sides and cork front/back.

At this point im willing to yank the intake and try their $23 gaskets to see if they work.

b5blue


Paul G

Man I feel for you. My  :Twocents: . You say distributor is old, is the mechanical advance in good shape? No broken springs or weights, etc. Firing order correct, meaning plug wires in the right holes on the dist cap? Is your ignition coil good? Can you swap in another? I know that the cork gaskets on the ends of the intake are sometimes too thick to even get the intake to bolt up. Mine were, had to just use silicone sealant on the ends. I used a Fel Pro gasket set with an RPM Air Gap intake. Is it possible that the cork end gaskets are not allowing the intake to seal to the head? Big vacuum leak at the intake ports? You questioned the timing chain. Did you install the chain? Are you sure it is installed correctly? Jumped time maybe?

Carb settings do not usually cause the engine to not run. A poorly adjusted carb will make the engine run poorly. If the idle screws are 1 1/2 to 2 turns out, and the idle setting screw is out far enough to keep the engine idling, it will idle if there are no other issues. You probably have many other issues to sort out first.   

Just my thoughts. Good luck! :2thumbs:
1972 Charger Topper Special, 360ci, 46RH OD trans, 8 3/4 sure grip with 3.91 gear, 14.93@92 mph.
1973 Charger Rallye, 4 speed, muscle rat. Whatever engine right now?

Mopars Unlimited of Arizona

http://www.moparsaz.com/#

nrt69

its vac advance but its not hooked up. wires set up correct.
i didnt install timing chain, carolina machine engines did. i saw the marks they used to line it up correctly when i got the long block so i doubt its installed wrong.
i do question the cork gasket after just now pulling the intake...

theres oil seepage past the intake/exhaust ports on the head. oil is on both sides of the gaskets, at the bottom, around the ports.

how much of a gap should there be at the front/back of the intake where it sits on the block? that cork gasket is considerably thicker than the gap i have when just resting the intake on the engine...maybe the cork did prevent the intake from sealing properly?


Paul G

I cant see how you even got the manifold bolts in the head using the cork. My holes werent even close to lining up. I ditched the cork right away. If I remember (dont count too much on that) the sealant was only about half the thickness of the cork. But, I think you found your problem. Keep us informed.
1972 Charger Topper Special, 360ci, 46RH OD trans, 8 3/4 sure grip with 3.91 gear, 14.93@92 mph.
1973 Charger Rallye, 4 speed, muscle rat. Whatever engine right now?

Mopars Unlimited of Arizona

http://www.moparsaz.com/#

nrt69

well, its not the intake gaskets.

nrt69

is there a way to troubleshoot timing chain and cam degree issues before tearing the front of the motor apart?
can my MP electronic distributor be so worn out it limits my ability to time my engine? (or give me a very narrow window of timing?)


b5blue

Pull the valve cover and get the valve train set up for firing on #1 to see what is indicated on timing mark. Kinda doubt the dizzy being bad or worn out, again the quality of starting and idle was greatly improved when I changed to a FBO set up dizzy with the vacuum advance working correctly. Mileage went up quite a bit too.

Musicman

As long as you follow Don's (FBO) instructions concerning how to properly set up and tune an engine to the letter, it's hard to go wrong.  :2thumbs:

nrt69

Quote from: b5blue on July 29, 2011, 07:35:51 AM
Pull the valve cover and get the valve train set up for firing on #1 to see what is indicated on timing mark. Kinda doubt the dizzy being bad or worn out, again the quality of starting and idle was greatly improved when I changed to a FBO set up dizzy with the vacuum advance working correctly. Mileage went up quite a bit too.

You mean set it up at TDC and ensure the valves are open/closed properly?

b5blue

Yes then you can see the relationship between crank and cam.

nrt69

if the timing chain was NOT installed at TDC, would i be able to tell by looking at the valves/rockers?

PS, before you do buisness with carolina machine engines....EMAIL ME!!

b5blue

Well more like TDC on the piston and where the rockers are positioned, they should be both relaxed, the push rods off any ramp on the lobes of the cam.  :scratchchin: (I'm kinda doubting they are a tooth off, but I've seen bigger mistakes in my days!)

nrt69

does anyone have any pics of a 360 timing chain and camshaft installation?
the chain only goes on one way? or multiple ways if using an aftermarket double chain?
does the cam connect to it only one way?
does the #1 have to be at TDC when installing the cam and timing chain?

b5blue


Chryco Psycho

of course I have seen cams ground so far off that it could still be as much as 13* off with the dots lined up , you really need to degree it

nrt69

and degree-ing it involves pulling the front of the motor off, right?


b5blue

I'm feeling your frustration,  :eek2:

Paul G

You had the engine built by a shop right? Have you questioned them about what it is doing? Could you pull it out and take it back to them and let them figure it out? Saves you a lot of trial and error, and grief. 
1972 Charger Topper Special, 360ci, 46RH OD trans, 8 3/4 sure grip with 3.91 gear, 14.93@92 mph.
1973 Charger Rallye, 4 speed, muscle rat. Whatever engine right now?

Mopars Unlimited of Arizona

http://www.moparsaz.com/#

nrt69

dont get me started about the engine builder (contact me before you do buisness with carolina machine engines!!!)
they are out of state and were all sorts of nice before they had my money and now they dont want to offer any assistance despite telling me that they would.
Nobody in my isolated small west TX town is competent enough, or cares enough, to help me either. SO, I get to learn how to diagnose and fix my problems the long hard expensive way.

nrt69

would doing a compression check help me narrow down the problem before i take the front of the engine apart?

maxwellwedge

It may or may not but I would do one anyway just to see if everything else is as it should be. A leakdown test would be a good thing as well....just to keep this shop honest.

I am still thinking there is something else causing your vacuum readings.....they are too low for your build.

Chryco Psycho

I am willing to fly in & help

heyoldguy

There is a way to get a rough check on the cam timing without removing anything but the left valve cover. Turn the engine over until #1 cylinder is at TDC with both valves closed (#1 fire). Now begin rotating the engine 360 degrees by hand. Watch the #1 cylinder rocker arms. As you rotate the engine the exhaust valve will begin to open and then start closing again. When the exhaust is about closed the intake will start opening. When both rocker arms are level, i.e. both intake and exhaust valves open the same amount, STOP. You are now at split overlap. Look at the timing marks on the damper, it should read around 0 to +5 degrees. If it is way off from that, you probably have a cam timing issue.

b5blue

Hey you did a much better job explaining what I meant!    :2thumbs:
Quote from: heyoldguy on August 05, 2011, 08:34:25 PM
There is a way to get a rough check on the cam timing without removing anything but the left valve cover. Turn the engine over until #1 cylinder is at TDC with both valves closed (#1 fire). Now begin rotating the engine 360 degrees by hand. Watch the #1 cylinder rocker arms. As you rotate the engine the exhaust valve will begin to open and then start closing again. When the exhaust is about closed the intake will start opening. When both rocker arms are level, i.e. both intake and exhaust valves open the same amount, STOP. You are now at split overlap. Look at the timing marks on the damper, it should read around 0 to +5 degrees. If it is way off from that, you probably have a cam timing issue.

nrt69

Quote from: Chryco Psycho on August 05, 2011, 05:18:59 PM
I am willing to fly in & help

The airport code is SJT. Let me know what your flight number is.

nrt69

Quote from: heyoldguy on August 05, 2011, 08:34:25 PM
There is a way to get a rough check on the cam timing without removing anything but the left valve cover. Turn the engine over until #1 cylinder is at TDC with both valves closed (#1 fire). Now begin rotating the engine 360 degrees by hand. Watch the #1 cylinder rocker arms. As you rotate the engine the exhaust valve will begin to open and then start closing again. When the exhaust is about closed the intake will start opening. When both rocker arms are level, i.e. both intake and exhaust valves open the same amount, STOP. You are now at split overlap. Look at the timing marks on the damper, it should read around 0 to +5 degrees. If it is way off from that, you probably have a cam timing issue.

thats an easy thing to do...since im not really looking forward to taking the motor apart. Am i rotating it a complete 360 degrees? And as i get to the 360 degree mark, thats where it should read 0 to +5 right?

nrt69

Quote from: nrt69 on August 06, 2011, 09:26:46 AM
Quote from: heyoldguy on August 05, 2011, 08:34:25 PM
There is a way to get a rough check on the cam timing without removing anything but the left valve cover. Turn the engine over until #1 cylinder is at TDC with both valves closed (#1 fire). Now begin rotating the engine 360 degrees by hand. Watch the #1 cylinder rocker arms. As you rotate the engine the exhaust valve will begin to open and then start closing again. When the exhaust is about closed the intake will start opening. When both rocker arms are level, i.e. both intake and exhaust valves open the same amount, STOP. You are now at split overlap. Look at the timing marks on the damper, it should read around 0 to +5 degrees. If it is way off from that, you probably have a cam timing issue.

thats an easy thing to do...since im not really looking forward to taking the motor apart. Am i rotating it a complete 360 degrees? And as i get to the 360 degree mark, thats where it should read 0 to +5 right?

tried this and its hard to gauge. the intake and exhaust rockers seem to be "even" or "level" (closed?) for a significant amount of time...ie theres alot of turning the motor over before either intake or exhaust rocer starts opening (moving downward). the intake and exhaust rocker seems to start moving at the 360 degree mark. am I reading this right?

nrt69

well, i didnt make it to the timing set yet. i did a compression check today and found most cylinders were only 90-115. A couple were only 72-85.
put some oil in the really low cylinders and got a big jump in one and a slight jump in the other.
Local engine builder says its probably the heads.

FLG

If you get a jump with oil it points to the rings not the heads.

nrt69

http://www.dodgecharger.com/forum/index.php/topic,82173.0.html

ill post their "findings" here after they take a look at the engine.

nrt69

its been 5 weeks since i returned my engine and they finally called me today.

they claim that my rebuilt eddy carb "has a lean condition" and my MP distributor "doesnt advance fast enough".