Timing all wrong, i'm lost. PLZ help
Race Director
Joined: Sep 1999
Posts: 11,361
Likes: 383
From: Plano TX
The dieseling is not the way to set timing. All that advance you've given it has been very hard on the bearings. Follow Lars' paper and set the timing correctly. To avoid dieseling you can shut it off in drive (automatic) or you can put it in 4th, release the clutch part way to create drag and shut it down.
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,391
From: At my Bar drinking and wrenching in Lafayette Colorado
Originally Posted by vetteguy112233
I was just told by Barry Grant that my 850 carb is downleg and should be annular. He told me that it's pumping way to much gas into the motor, so he told me that's why the more timing I give it, the better it will run, but he recommends boxing it up and sending it to them and for about $85 they will convert it to annular. Just thought I would let you guys know what they told me.
You still need to set your timing up right. You indicate that you cranked it up to 20 and then up to 40 where it finally ran well. What was the total? You need to set it up for total timing. I'll bet if you set your timing to 36 total, you will get 18 to 20 initial. Then hook up your vacuum advance to manifold vacuum for an additional 16 degrees, and you'll be at 36 degrees timing at idle and still be in-spec at WOT. This will allow you to close your idle speed down. Balance out your primary and secondary idle speed so you're pulling air through the secondary side, and you will eliminate the run-on.
"90% of all carb problems are ignition and timing problems"
The annular booster change is a band-aid. You need to fix your timing and set the carb up correctly.
Burning Brakes
Joined: Apr 2004
Posts: 847
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From: Des Allemands LA
Originally Posted by vetteguy112233
Ok, I've verified that my balancer is correct. Exactly on top of the compression stroke it lines up with 0. I also took the distributor cap off and verified that the roter is pointing at #1. I decided to adjust it to 12 degrees BTDC and I can up the idle and it seems to run just fine, but hesitates very badly to shut off, so I bumped the timing to 20 (this is all at idle and no vacuum connected) and it seems to run about the same, maybe a little better and the first time I shut it off, it didn't hesitate at all, so I took it out and drove it for about 10 minutes, but when I got home, it hesitated for about 3 seconds to shut off. Last time I adjusted the timing I just adjusted it up and up and up until I got the least hesitation and that's how I got to 40 (this is a correction from my original post, it was actually at 40, not 50).
Any other ideas?
Any other ideas?
ltlevil
Race Director
Joined: Feb 1999
Posts: 19,659
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From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
One thing that has me concerned is the amount of timing he is seeing. Wonder if he has the wires one post off from where they should be on the cap. I have done this and it really makes you see some crazy numbers but the car will run great.
Thread Starter
Racer
Joined: Dec 2005
Posts: 399
Likes: 0
From: Kearns UT
Ok, hopefully I did this right. I set the motor to 18 at idle no vacuum. When I open the throttle up it goes to about 30 still without vacuum and then when I connect the vacuum advance (still the bad one, haven't got a new one yet) to manifold vacuum it jumps to about 40 at open throttle. There was still a lot of hesitation when I turned it off. Am I doing something wrong?
Team Owner
Joined: May 2001
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From: Exiled to Richmond, VA - Finally sold my house in Murfreesboro, TN ?? Corner of "Bumf*&k and 'You've got a purdy mouth'."
CI 6-7-8 Veteran
CI-VIII Burnout Champ
St. Jude Donor '06-'10, '13
You may have a wiring problem. Your alternator may be feeding power back into the system even when the ignition is turned off. If that is the case the distributor / coil are still getting power even when the key is turned off, and then it keeps running until the gas runs out. I had this problem on a drag race car after we installed an alternator.
Put a test light / meter on the wire that is going to the distributor / coil. Get the engine running and check to make sure you see voltage. Have someone turn the key off and it should go to zero volts instantly. If not then you have a problem.
Put a test light / meter on the wire that is going to the distributor / coil. Get the engine running and check to make sure you see voltage. Have someone turn the key off and it should go to zero volts instantly. If not then you have a problem.
Racer
Joined: Jan 2006
Posts: 288
Likes: 1
Cranking
When you first crank the car, does it fire right up, or does it turn over a bit first? Also, does it crank the exact same way when you first crank it, as opposed to driving it, & then cranking it up right away, afterwards?
I agree with Lars' timing info. If you've done that correctly, then there must be air, fuel, & spark coming from somewhere when the car is turned off.
I agree with Lars' timing info. If you've done that correctly, then there must be air, fuel, & spark coming from somewhere when the car is turned off.
Race Director
Joined: Sep 1999
Posts: 11,361
Likes: 383
From: Plano TX
Originally Posted by vetteguy112233
Ok, hopefully I did this right. I set the motor to 18 at idle no vacuum. When I open the throttle up it goes to about 30 still without vacuum and then when I connect the vacuum advance (still the bad one, haven't got a new one yet) to manifold vacuum it jumps to about 40 at open throttle. There was still a lot of hesitation when I turned it off. Am I doing something wrong?
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Thread Starter
Racer
Joined: Dec 2005
Posts: 399
Likes: 0
From: Kearns UT
It has always seemed to fire up within the first turn or two when warm. When cold it takes 4-5 maybe more turns to finally get it started. It does seem to fire a lot better now that I'm at 18 at idle, no vacuum, and if I remember right it fired even better at 12, but "dieseled" when trying to shut the motor off. I was told yesterday that my "hesitation" is called "dieseling". I did try putting the car in 4th gear, slowly letting out on the clutch and then shutting the motor off and it DID NOT diesel, when doing that, but if I just shut the car off it does.
