CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.
My '70 C/10 - The Rat Bastard... [Won't Idle.]
- Thread starter TheBeast_88K5
- Start date
TheBeast_88K5
Banned
Wow, do I feeeeeeeel stupid.... 
I had my engine at TDC#1, when I initally installed my dizzy....
NOT 16* advanced, like it shoulda been.
So, when I "advanced" my motor, w/ the Dizzy already installed, I was retarding my Dizzy.
..And, being a bit retarded, myself.
Fixed it, now idles AMAZING.... Its a MUCH happier motor on 16* of ACTUAL advance.
I got the Idle Mixture correct enough to Idle for a few seconds,
But I think it has vacuum leak somewhere, thats causing it to stumble/stall.
Gotta pick up a can of carb cleaner, and find it.
I had my engine at TDC#1, when I initally installed my dizzy....
NOT 16* advanced, like it shoulda been.
So, when I "advanced" my motor, w/ the Dizzy already installed, I was retarding my Dizzy.
..And, being a bit retarded, myself.
Fixed it, now idles AMAZING.... Its a MUCH happier motor on 16* of ACTUAL advance.
I got the Idle Mixture correct enough to Idle for a few seconds,
But I think it has vacuum leak somewhere, thats causing it to stumble/stall.
Gotta pick up a can of carb cleaner, and find it.
Wow, do I feeeeeeeel stupid....
I had my engine at TDC#1, when I initally installed my dizzy....
NOT 16* advanced, like it shoulda been.
So, when I "advanced" my motor, w/ the Dizzy already installed, I was retarding my Dizzy.
..And, being a bit retarded, myself.
Fixed it, now idles AMAZING.... Its a MUCH happier motor on 16* of ACTUAL advance.
I got the Idle Mixture correct enough to Idle for a few seconds,
But I think it has vacuum leak somewhere, thats causing it to stumble/stall.
Gotta pick up a can of carb cleaner, and find it.
fuel/air mixture should be 2 turns out.. done... they will never make it stall unless they are turned all the way in..
I prefer ether for vac leaks any day.. carb cleaner makes motors stall, ether makes it pick up rpm's.. VASTLY better diagnostic tool imo for vac leaks, as long as you don't start any fires...
TheBeast_88K5
Banned
I have my Fuel at 2.5, and my Air at 2.0....
For the 15 seconds that it did idle, it sounded fantastic.
But, im pretty sure theres a massive vaccum leak somewhere.
Or, my pcv being plugged (at the carb) might be causing it to act up.
**My PCV is running off manifold vacuum.
For the 15 seconds that it did idle, it sounded fantastic.
But, im pretty sure theres a massive vaccum leak somewhere.
Or, my pcv being plugged (at the carb) might be causing it to act up.
**My PCV is running off manifold vacuum.
it's just left and right bank, not fuel and air.. they should be the same turns out, 2..
pcv is fine off any vac source under the throttle blade..
pcv is fine off any vac source under the throttle blade..
Mike you could try plugging all the vac ports on the intake and carb...then hook them up one at a time to see if any vac sources have a leak (vac booster/pcv/timing, etc) Is your timing set at 16* static (no vac advance)? And what does the timing curve look like (amount of timing advanced by the dist weights as the rpm goes up). Make sure those things are working correctly before messing around with the carb too much.
And as Paul said...those a/f mixture screws should be about 2 turns out and both the same number of turns out from their seated position...you can play with them a bit; 1/2 turn more or less to see if vacuum and rpm goes up (a good thing in this case) but generally 2 turns is pretty close to perfect for these carbs.
Just noticed this...does the valve cover breather go to the carb or intake vacuum source? The PCV should, the breather should be open to atmosphere.
And as Paul said...those a/f mixture screws should be about 2 turns out and both the same number of turns out from their seated position...you can play with them a bit; 1/2 turn more or less to see if vacuum and rpm goes up (a good thing in this case) but generally 2 turns is pretty close to perfect for these carbs.
Just noticed this...does the valve cover breather go to the carb or intake vacuum source? The PCV should, the breather should be open to atmosphere.
TheBeast_88K5
Banned
The "PCV" port, on the carb, is capped.
The PCV breather, on the left valve cover, is attached to a fitting coming out of the manifold.
Should I block off the manifold, and the put the PCV where its supposed to go?
Then, cap off all the vac ports, and attach items one-by-one?
Seems about right...
Edit: Ad, adjust screws to "2" turns.
The PCV breather, on the left valve cover, is attached to a fitting coming out of the manifold.
Should I block off the manifold, and the put the PCV where its supposed to go?
Then, cap off all the vac ports, and attach items one-by-one?
Seems about right...
Edit: Ad, adjust screws to "2" turns.
TheBeast_88K5
Banned
Btw... I know very little about carbs.
The way you guys see Slushbox's, I see Carb's.
The way you guys see Slushbox's, I see Carb's.
As I understand it, there's basically the two flavors of vacuum, either ported or manifold. Ported changes with throttle, so you use that for the dizzy and emissions, but manifold is usually for the PCV, the vacuum accumulator ball used for the climate controls, and I think the power brakes.
I know there's a ton of connectors on the carb in various sizes, but they're either the one vacuum or the other, based on whether they're above the throttle plate or below, so it's not as complicated as it seems on the surface.
At least that's my theory.
-- A
I know there's a ton of connectors on the carb in various sizes, but they're either the one vacuum or the other, based on whether they're above the throttle plate or below, so it's not as complicated as it seems on the surface.
At least that's my theory.
-- A
TheBeast_88K5
Banned
I need someone to come here, and tell my I'm dumb, while they fix it...
BLIDVL
1/2 ton status
To find vacumm leaks a propane torch works just like ether and cheaper,not lit of course. Your carb mixture screws should both be at two turns out. Make sure your carb is clean first, seriously take it off and crack it open, not hard to do and gives you a good indication of the state of the rest of your fuel lines etc.
I need someone to come here, and tell my I'm dumb, while they fix it...
I stopped doing that after an incident with a member who won't be named who is, umm, electrically challenged.
While I had my back turned for a few seconds to talk to the neighbor, he managed to connect the battery backwards and blew out all the fusible links, plus a few assorted smaller wires and generally made a mess of the engine compartment.
I mean, I don't even know how you do that as the wires barely reach the wrong way, plus I thought everybody knew red was positive etc ... but nooooooo.
Though upon reflection, maybe he's color blind.
Anyway, after that, I'll help wrench, but specialty items at most I will advise or point, and the truck's owner does the work!-- A
I need someone to come here, and tell my I'm dumb, while they fix it...
no can do man. carburetors and distributors are a different language to me...
I guess I am going to have to come.
I will see if I can make it Saturday.
I should be back Friday night.
I will see if I can make it Saturday.
I should be back Friday night.
TheBeast_88K5
Banned
Oh, jeezus, i wasnt serious....
It'll be running tomoro.... After I carve pumpkins.
Ive been reading a LOT about vacuum, and timing.
I meant that the INSIDE workings of a Carb, might as well be rocket science to me.
All I have to do is find my vac. leak, and go from there.
It'll be running tomoro.... After I carve pumpkins.
Ive been reading a LOT about vacuum, and timing.
I meant that the INSIDE workings of a Carb, might as well be rocket science to me.
All I have to do is find my vac. leak, and go from there.
Last edited:
I use a vacuum gauge to set my Gas/Air rations.
The old 2 screws out method gets you in the ball park, but using a gauge lets you zero in to get max performance out of it.
It's supposed to be a quick easy adjustment. As you go up in elevation it's recommended that you adjust the ration 1 stage per 1000ft. The only way to measure stages is with the gauge.
I have to take mine with me when I hit the mountain trails because I live at sea level and some of the trails hit 5-6K'.
The old 2 screws out method gets you in the ball park, but using a gauge lets you zero in to get max performance out of it.
It's supposed to be a quick easy adjustment. As you go up in elevation it's recommended that you adjust the ration 1 stage per 1000ft. The only way to measure stages is with the gauge.
I have to take mine with me when I hit the mountain trails because I live at sea level and some of the trails hit 5-6K'.
TheBeast_88K5
Banned
Dammit,... So, I actually need my own vacuum guage?
I have one you can use.
I also use that to adjust my carb.
You adjust for max vacuum.
I also use that to adjust my carb.
You adjust for max vacuum.
TheBeast_88K5
Banned
I know... No worries.
I'm just gonna pick one up.
Apparently its a handy thing to have around....
Gotta go to the parts store for some stuff, anyhow.
TheBeast_88K5
Banned
Couldn't get my hands on a vac gauge.
But, I did block off all my vac ports and put on an air cleaner.
Low and behold it ran good!
After about 5 mins, it's started this dying mess.
I don't even know what terminology to use.
But, I did block off all my vac ports and put on an air cleaner.
Low and behold it ran good!
After about 5 mins, it's started this dying mess.
I don't even know what terminology to use.
Last edited by a moderator:
