Truer words have never been spoken.
This again.... 4bbl on a 318 with a 2bbl
- Thread starter abcdefghii
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Yup. That's your starting point.
Dartswinger70
Well-Known Member
Aww man...did ya ever get the right length throttle cable? why is it idling 2000? can you back the idle down with the screw or is your throttle cable and auto trans linkage holding it open do you have return springs hooked up?
abcdefghii
Well-Known Member
Let's see..
Throttle cable using the same one that I used with the 2bbl. It has worked fine and now it's connected to the right bracket should be ok, just need to tidy up the routing.
High idle, I haven't done much about that yet. I did rotate the choke housing back to center (it wasn't from factory) which in the one start I did seemed to have made a difference. I do think the 2bbl bracket was holding it open slightly as well which wasn't helping
Return springs hooked up as of yesterday.
Next up is confirming kickdown cable install, making sure no open vacuum ports and see how it starts/idles.
Oh, I do have something I'm not sure about. On the 2bbl I had a small vacuum line hooked up at the base on the rear, it routes into the cab. Assuming it's something related to the factory AC, where should it go on the new carb? I have 2 small ports on the front, one says vacuum advance for emissions controlled, the other non emissions controlled.
I don't know if my truck was emissions controlled and now isn't (PO removed a bunch of stuff, left things like the charcoal canisters there, but not hooked up).
So I'm left deciding where to connect distributor vacuum advance and additionally where to connect that line that goes through the firewall. I'd guess distributor at the timed vacuum and mystery hose at the manifold vacuum?
Hook your distributor to "ported vacuum" and your interior feed for the heater to "unported vacuum." Look closely, the ported vacuum nipple will be higher up from the base than the unported which is closer to the base of the carb. Ported doesn't produce vacuum at idle and unported produces a constant supply. "Timed vacuum" in this photo is ported. See the difference in height between the two?
340six
King Of Bling
The Ported Vacuum is where to hook up the vacuum advance canister on distributor.
Make sure all caps are good. Old and new ones can leak. Spray carb cleaner at intake gasket, carb base ect to check for leaks.
Looks like I was sleeping at the tree and Mike got it.
I was looking for a video of how to find vacuum leaks.
Start with simple things that require fast idle leaks or timming
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340six
King Of Bling
If you have to have the idle fast to run check hoses for cracks/ holes, vacuum caps. Intake and carb gaskets.
abcdefghii
Well-Known Member
Great, on the old carb the distributor vacuum was on the higher port and the heater at the base, so that makes sense.
The truck does idle fine, just needs the high idle adjusted down some is all. Once the choke opened last time I ran it, the idle dropped to about 950 or so. Still a little high, but easily adjustable.
The truck does idle fine, just needs the high idle adjusted down some is all. Once the choke opened last time I ran it, the idle dropped to about 950 or so. Still a little high, but easily adjustable.
Dartswinger70
Well-Known Member
good to hear you can ajust the idle down. Im guessing you want it set somewhere between 7 an 900 rpm it depends on auto vs manual trans. over 1000 rpm is high in my opinion but Id look it up see what a shop manual says
abcdefghii
Well-Known Member
If I remember correctly the sticker on the fender says 650rpm for curb idle, but that's with the 2bbl set up.
I went out to the shop just now, lowered the high idle some and it's starting an running well. Smells a bit rich, but I need to get it fully warmed up before doing much more. I think the timing also needs a tweak, just to find that sweet spot. Starts on about the 3rd crank, used to start on the 1st before swapping to the Pertronix distributor.
Got a list of things left to confirm/adjust:
High idle
Curb idle
Timing
Mixture
Throttle - basically make sure I'm getting full range of motion.
Kickdown cable - same as above, make sure it's getting full range and adjust as needed.
Forgot one - check and adjust fuel pressure, looks to be right at 6psi at idle, but again need it to be fully warmed up to really check.
Getting closer to the finish.
I went out to the shop just now, lowered the high idle some and it's starting an running well. Smells a bit rich, but I need to get it fully warmed up before doing much more. I think the timing also needs a tweak, just to find that sweet spot. Starts on about the 3rd crank, used to start on the 1st before swapping to the Pertronix distributor.
Got a list of things left to confirm/adjust:
High idle
Curb idle
Timing
Mixture
Throttle - basically make sure I'm getting full range of motion.
Kickdown cable - same as above, make sure it's getting full range and adjust as needed.
Forgot one - check and adjust fuel pressure, looks to be right at 6psi at idle, but again need it to be fully warmed up to really check.
Getting closer to the finish.
Dartswinger70
Well-Known Member
Keep in mind youll have to get timing right then go back and check and or reset the carb. Thats the fine tuning, it takes a couple times going through it
abcdefghii
Well-Known Member
Yep .. the timing - rpm - mixture dance
Yep. Welcome to the party. I adjust the idle speed first then the timing. Then go back and check the idle speed.
Not to say that Ehrenberg is the least expensive way to go, or the only source for the same things, but he does sell quality stuff.
abcdefghii
Well-Known Member
Getting there, throttle pulls the kickdown lever all the way, I'm a little concerned that it looks like the cable slipped a little so drew a mark with a sharpie on there.
Does this bracket look like it should be flipped the other way?
Just trying to see if I can straighten the path a little (and maybe get a bit more than just over half an inch sticking out at the carb end).
Later on I'm going to see if I have full travel with the throttle, might be hard to tell from the drivers seat though, and start it up, make some adjustments and then maybe drive it.
Likely be nervous that first drive.
Does this bracket look like it should be flipped the other way?
Just trying to see if I can straighten the path a little (and maybe get a bit more than just over half an inch sticking out at the carb end).
Later on I'm going to see if I have full travel with the throttle, might be hard to tell from the drivers seat though, and start it up, make some adjustments and then maybe drive it.
Likely be nervous that first drive.
abcdefghii
Well-Known Member
Got it started, warmed up and idling. Rotated distributor until it sounded best. Shut it off, went to start and it's cranking real slow and struggles to start.
Moved distributor a little at a time until it starts. Shut it off, go to restart, same thing. Weird.
Curb idle also doesn't seem to get much lower than 900. In fact the screw is (was, I put it back in some) turned out so much it wasn't contacting the linkage on the carb. Putting it in gear drops the rpm to about 600, just rpm in P seems high to me.
I'm sure it's something really really basic, I'm just fumbling around trying to figure it out.
Moved distributor a little at a time until it starts. Shut it off, go to restart, same thing. Weird.
Curb idle also doesn't seem to get much lower than 900. In fact the screw is (was, I put it back in some) turned out so much it wasn't contacting the linkage on the carb. Putting it in gear drops the rpm to about 600, just rpm in P seems high to me.
I'm sure it's something really really basic, I'm just fumbling around trying to figure it out.
Disconnect the throttle cable from the carb, see if it will idle better. Thinking cable is not letting carb return to full idle.
abcdefghii
Well-Known Member
I was thinking along the same lines, disconnected it and carefully watched the linkage though and no movement. 99% sure it's at full rest.
If I get time to work on it this weekend I may take a video to show how it's acting. Doesn't make much sense to me.
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If it's dragging the starter when hot, it has too much initial timing. The throttle and kickdown cables have NOTHING to do with a dragging starter when hot. Get a light and stop the guesswork.
abcdefghii
Well-Known Member
Just to rule it out, I'm charging the battery. It was flat and I used a jump pack, but going to fully charge it before doing anything else.
Then plug this in and see what it's saying
Then plug this in and see what it's saying
And a tach!!!!
The timing it had before the swap was measured at 650 rpm.
The tach is needed because above some rpm, the advance will be adding timing.
Write down the rpm with all timing measurements. Saves a little headaches.
Also remove the hose from the distributor and put a golf tee in it. This removed the possiblility of any vacuum advance while taking the timing.
The timing it had before the swap was measured at 650 rpm.
The tach is needed because above some rpm, the advance will be adding timing.
Write down the rpm with all timing measurements. Saves a little headaches.
Also remove the hose from the distributor and put a golf tee in it. This removed the possiblility of any vacuum advance while taking the timing.
abcdefghii
Well-Known Member
So something must not be right, warmed up, choke all the way open, idle nicely, timing light is reading 40° advance which, now I'm no expert, but that seems absurdly high.
Plug wire off by one?
Before I clocked the distributor I put a cork in the hole, rotated the engine until the cork popped out, then put a screwdriver in and rotated until it stopped moving upwards. Then dropped distributor in, looked where the rotor was, pulled it out and rotated the gear until it was also pointing reasonably close to #1 plug.
Plug wire off by one?
Before I clocked the distributor I put a cork in the hole, rotated the engine until the cork popped out, then put a screwdriver in and rotated until it stopped moving upwards. Then dropped distributor in, looked where the rotor was, pulled it out and rotated the gear until it was also pointing reasonably close to #1 plug.
PRH
Well-Known Member
Unhook the vac advance, and set the timing at 6-10* btdc at a normal idle speed(6-800).
Then reattach the VA hose……then reset idle speed if needed.
Then reattach the VA hose……then reset idle speed if needed.
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