360 just not right after RE-rebuild

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tjgp360

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the engine was just "rebuilt" less than 2 years ago by some screw ball mechanic,.....thats another story

after this "rebuild" i noticed the car often stalled whenever i used the brake, i blamed the leaky brake booster, so in the meantime i just up the idle a tad to to keep me going

a couple , months after i remove the lean burn and install a jegs ignition kit

soon after engine started to make a ticking/tapping sound (like a bad lifter)

a few months later the timing cover gasket blew causing coolant to spew everywhere so i park the car for a week while i get ready for my own rebuild

I bought:
summit cam -6901 with lifters
camshaft gasket change kit
edelbrock 1406 carb
thermoquad carb (rebuilt it my self)
stock cast iron 4bbl intake
edelbrock performer intake
Power brake booster
Master cylinder

DURING THE RE-REBUILD

the rebuild went smooth, but during the tear down i noticed that a rod broke through a rocker arm, so i hit the junkyard for a replacement and i also noticed that 2 lifter were worn to hell 1 actually had a small pin sized hole in it, needless to say the camshaft lobes they rode on were practically gone.

I installed the edelbrock carb simply because :

1. im not sure if i totally trusted my rebuild skills

2. the new intake gasket had the heat crossover blocked and well...the edelbrock has an electric choke

3. the carb gasket that i bought fit the edelbrock but was too small for the manly secondaries of the thermoquad:burnout:

AFTER RE-REBUILD

after everything was assembled i took some time to tinker with the distributor and it started right up:prayer: but i got too happy too fast:banghead:

KNOWN PROBLEMS

i got it to idle okay but now when you drop it into gear it likes to drop from 580 to 640 rpm down to 430 450 rpm then stalls!!!!

im not sure how to tune this damned carb, all i did was unscrew the 2 screws 2 1/2 turns.

Sometimes i can hear a hard ping other times i don't

the carburator spits or back fires sometimes when i snap the throttle wide open then stalls out....

i cant even drive down the street and turn around with out it stalling 8 times!!:mumum:

ON TOP OF THE THE BELT MAKES A DAMN NOISE NOW WHEN I TURN THE WHEEL HARD!!!!:angryfir:


i need some help or advice or something because even though my car isn't the prettiest i still love the damn thing to death and im just HOPING i can make the Woodward Dreamcruise
 
How much initial timing is my first question.

That idle is REALLY low. Bump it up to 750-800 in park/neutral.

If you are running the performer intake/ede carb, do you have the square bore plate under the carb?

Thermoquad, you're not gonna get much help from me.
 
I would save for a good carb. The eddys didn't work good for me so I went with a holley street avernger. It prolly needs to be tuned. Is it stock rockers or adjustable? Is it in time?
 
crackedback said:
How much initial timing is my first question.

That idle is REALLY low. Bump it up to 750-800 in park/neutral.

If you are running the performer intake/ede carb, do you have the square bore plate under the carb?

Thermoquad, you're not gonna get much help from me.
Click to expand...

:blob: thanks for the reply!!

let talk about idle...how do i get the correct idle speed? i got mine by rotating the distrubutor until its 0 advance.... i was always under the impression that 750-800 is high and any where from 500 to 650 was the sweet spot.:eek:ops: lol i guess im not used to my cam yet because this things sounds like a caged beast above 700 rpm more rump than i had before

and i have no plate for the carb, the carb is spread bore as well as the intake
 
Turn it so it's AT LEAST 10* BTDC and better at 14-16 IMO. That will help the barfing out the carb, it's retard if the timing mark is at "0". You'll need to check total to figure out just how much timing is in the distributor.

To make things easier, turn the balancer timing mark to 10* bdtc and then put a mark on the balancer at 5 abdc. That way you have a reference mark when doing the initial timing. That new mark at "0" on the cover is 15BTDC. You can do another mark doing the same thing to get 30* BTDC for checking total timing.

You have a different cam than a "stock" engine. Throw any stock timing, idle setting out the window.

Once you get the timing reset, adjust the carb idle speed and mixture screws.
 
bamamopar said:
I would save for a good carb. The eddys didn't work good for me so I went with a holley street avernger. It prolly needs to be tuned. Is it stock rockers or adjustable? Is it in time?
Click to expand...

the rockers are stock even the one i replaced is stock, and what do you mean in time????
 
crackedback said:
Turn it so it's AT LEAST 10* BTDC and better at 14-16 IMO. That will help the barfing out the carb, it's retard if the timing mark is at "0".

You have a different cam than a "stock" engine. Throw any stock timing, idle setting out the window.

Once you get the timing reset, adjust the carb idle speed and mixture screws.
Click to expand...

ok so i should


  1. plug the ported vacuum port
  2. turn the distibutor until its +10 degrees?
  3. then start messing with the carb...
soooooo i shouldnt touch the distributor when trying to get the idle right AND i want the idle to be anywhere from 750 to 800 ?

:newb:
 
UNDO the vacuum advance line and PLUG IT!

AT LEAST 10* and ideally in the 14-16 range

Or two other ways to get there...

Set the idle at 700 right now, feed more timing into the engine, if it picks up rpm, reset the idle to 700 and do it again a few degrees at a time until it stops picking up RPM. You'll reach a point where it might change very slightly. Find the point it stops making decent gains. That's where you can set it for the time being.

Or hook a vacuum gauge up and advance timing until it reaches highest vacuum at a constant idle 700, advance reset idle... then back it of 1" from max and reset the idle to 700 or whatever.

IMO, your expectation of an idle level is WAY TOO LOW... I wouldn't try to run that at anything less than 750 in park.

You MUST get the initial timing setting straightened out before adjusting the carb.
 
One step at a a time.


Like already said, if you have a standard performer and not a performer rpm intake, you probably have a spread bore intake (big secondaries). Be sure the gasket is correct to mount your edelbrock carb to your performer intake. Call edelbrock if you are not sure which gasket to use as I cant remember (we have an edelbrock thunder avs carb on a performer spreadbore intake on a 440) Works great. I believe as long as you have a gasket that is wide enough to go out to the edge of the intake flange where the carb sits, you will be fine.
You need to verify there are no vacuum leaks on the intake - carb and manifold - heads (one way to test is get a can of starter fluid or carb cleaner and gently squirt around base of carb then also where the intake meets the heads and see if the idle revs up by itself).

Next verify plug wire order is right, and there are no bad or melted plug wires near headers or manifolds.
I assume you have new plugs.

Next, verify the ignition timing for initial and max. Others on here have good advise on timing settings. I would leave the vacuum advance disconnected until you get the motor tuned and running nice w/o it.
On edelbrock carbs you screw the front screws all the way in, then back them out 2.5 turns each. That is your starting point. Start the motor, then screw them in very slowly one at a time until the idle drops a little, back each one out and stop when you achieve best idle. After that adjust your idle speed with the screw on the throttle stop.

I dont know about rocker arms, are there left and right RAs? Could you have a rocker arm issue holding a valve open?
 
i have no clue what my vacuum is at idle i don't have a gauge though i do have a advance timing light

cracked back that second suggestion is so genius it just might work!!!! lol

ok so that should take care of the idle And spitting problem?
 
You're still need to be aware that the total number may get out of hand, like in the 40's. So a re-curve of the distributor may be in order.
 
Rice Nuker said:
One step at a a time.


Like already said, if you have a standard performer and not a performer rpm intake, you probably have a spread bore intake (big secondaries). Be sure the gasket is correct to mount your edelbrock carb to your performer intake. Call edelbrock if you are not sure which gasket to use as I cant remember (we have an edelbrock thunder avs carb on a performer spreadbore intake on a 440) Works great. I believe as long as you have a gasket that is wide enough to go out to the edge of the intake flange where the carb sits, you will be fine.
You need to verify there are no vacuum leaks on the intake - carb and manifold - heads (one way to test is get a can of starter fluid or carb cleaner and gently squirt around base of carb then also where the intake meets the heads and see if the idle revs up by itself).

Next verify plug wire order is right, and there are no bad or melted plug wires near headers or manifolds.
I assume you have new plugs.

Next, verify the ignition timing for initial and max. Others on here have good advise on timing settings. I would leave the vacuum advance disconnected until you get the motor tuned and running nice w/o it.
On edelbrock carbs you screw the front screws all the way in, then back them out 2.5 turns each. That is your starting point. Start the motor, then screw them in very slowly one at a time until the idle drops a little, back each one out and stop when you achieve best idle. After that adjust your idle speed with the screw on the throttle stop.

I dont know about rocker arms, are there left and right RAs? Could you have a rocker arm issue holding a valve open?
Click to expand...

The carb gasket i have is the right one for the edelbrock, it was just the wrong one for the thermoquad and i dont have new plugs yet because i was planning to drive to the store with the car once it was running
and then get the plugs lol :banghead:

i know it ran well before with the same plugs i just thought they would be
well enough to take me up the street

as far as rocker arms go they are all stock, i even kept the stock spring because of good reports with this cam and spring combo, the heads are only temporary for now, i plan to get some 318 302 heads and open the intake seats to 2.02, that should match my intake perfectly and bump my compression at the same time
 
crackedback said:
You're still need to be aware that the total number may get out of hand, like in the 40's. So a re-curve of the distributor may be in order.
Click to expand...

okay so i should watch out for how much i advance it?

oh and should i ever take a hex and change the advance? because i never did that even from day one i just adjusted the air gap and slapped it on
 
That hex key in the advance can has NOTHING to do with setting the initial timing, LEAVE IT ALONE.

Think of a house and the way you build it. In ignition timing world...

Intitial is the foundation. You need it right before putting up the walls. Once you find the proper initial number, you need to have a total number in mind say 34. If you initial is 14, then you need 20* of mechanical in the distributor. That may require taking the distributor apart to set.

DO NOT be concerned with the vacuum advance or the total number when starting out. You ONLY need to be concerned with getting the initial timing number set and locked in. Like Rice Nuker said... one step at a time.
 
ok thank you ALL. i will check back with you all later tomorrow and tell you how it goes. Although im so excited about the new info im tempted to try now lol
 
okay

what i did first was unplug the vac advance line and blocked it off at the carb

after i started the car i rotated the dist. to bump up the rpms, i ended up having to rotate the wires for the range i needed.

SO after i rotated the Dist. right before the point the rpms fell off i locked it into place

I set the idle at around 750- 800. then i adjusted the mix screws....it seems that i cant screw them in much from 2 1/2 without the idle speed being affected

so after this point im happy and everything sounds well

I drop it into gear and it sputters and stalls.

put it in neutral,start it and rev a little

drop it in gear and give it a little gas

then i hear a pop and a nice THUD.

i tried starting it again it ran fine and sputtered out

now it wont start and it has slow crank like the battery is dead
and some time in the middle of the crank its stops with a thud

......... well i think a big part of it is i might be out of gas

i will get some gas later and try again
 
I think, at this point, you need to do a little research on how to properly install the distributor, wires, and set base timing. You have the timing initial up so far it doesnt have the power to turn over with the starter. You need to put in the distributor, then place the wires, then set the timing, then work on the carb. Timing always first. Carb after. You should not have to "move wires" to get what you need. So put it back the way it was and start over. Patience. You dont have the experience, so dont feel bad. We were all there before...
 
tjgp360 said:
okay


now it wont start and it has slow crank like the battery is dead
and some time in the middle of the crank its stops with a thud
Click to expand...

That's probably kick back. It happens when the timing is too far advanced, and the engine trys to fire before the piston is at the top, pushing against the piston on the way up.

Pinging and spitting back though the carb is most likely too much advance in the timing, or the carb is too lean. Get the timing right before fooling around with the carb. Those Eddy 650 run pretty much OK out of the box, but can always stand some tuning.

The suggestion about messing with the timing to get a good idle is OK, but only after everything else is in order. I would set the timing at about 10 degrees before TDC, (vacuum unplugged) then set the idle at 800-850, and go from there. The spec for the 73 340 was 750 @ 2.5 degrees BTDC for Auto , and 900 @ 5 degrees BTDC for manual tranny. DO NOT put in more than 10 degrees of timing until you know how much timing the distributor mechanical advance is adding in. I've seen some factory distributors add in an extra 30 degrees, which is way more than u need (40 total). Your engine will likely be happiest at 32 to 38 total (w/out vacuum).

Just for reference, rotate the engine to where the timing mark is exactly at 0. The rotor in the distributor should be pointing at the intake manifold bolt closest to front of the engine on the cylinder 1 side. (it may be 180 degrees off, just rotate the engine another full 360 degrees). The crank turns 2x for every 1 time the cam and distributor rotate.

See pics below:
 

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Here is a pic of my distributor install on my 360 (408 stroker).

Red line - where rotor should point at TDC
Blue line - where the #1 plug wire aligns to the coil plug wire (center). Mine is about 16 degrees advanced. 10 degrees would have those lines (red and blue) closer together (a more acute angle)
Purple line - where my vacuum advance points at 16 degrees BTDC
Green - distributor rotation.

To put in more advance, rotate the distributor counterclockwise.

When installed, your should look fairly close to this illustration.
 

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Factory manual on setting time, and the 340 specs
 

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Hey guys.. it was out of gas LOL

But after gas and a battery jump it was up and running

I think there is TOO much advance because it still "kicks back" on start up

If I read my timing light right the advance is like 45.4

And on top of it all it still stalls in gear
 
It's a system of things working together. You have at least two not working right..lol. Patience... You need to get the timing back down to about 15° initial, with the vacuum plugged and the idle speed below 800rpm. Once that's done, post again and you can start working on the carb.
 
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