One tooth off??
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From: PARADISE
St. Jude Donor '09-'11-'12-'13-'14
One tooth off??
Since the search function is worthless here now, can anyone give me some symptoms of a distributor being one tooth off? I don't think it is, but I've been chasing a carb problem and that might be the wrong thing to chase. Timing is 10 initial and 26 with the vacuum at 1000 rpm, but I'm getting a pop in the exhaust when I punch it and RPM is rising through 3K. This is on a test stand, not in the car and I'm trying to get the jetting close before it goes in.
Speed Demon carb came with #77 primary and 83 secondary jets, but I'm at nearly 5000 feet and they say one jet size for every 1500 ft. ASL. I'm down to #74 and #80 and it still blackening the plugs so it is obviously rich.
Any thoughts appreciated.
Speed Demon carb came with #77 primary and 83 secondary jets, but I'm at nearly 5000 feet and they say one jet size for every 1500 ft. ASL. I'm down to #74 and #80 and it still blackening the plugs so it is obviously rich.
Any thoughts appreciated.
Melting Slicks
Joined: Aug 2004
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From: Riverhead New York
Clay, Retime the engine from scratch. Pull #1, bring to top of Comp. stroke, align timing mark to TDC, drop the Dist. in proper sequence, (rotate Oil Pump as needed). Then you can use a Timing Light to finesse your Timing. Al W.
I'm thinking you have something wierd going on with that Carb.. Do you have another available?
I'm thinking you have something wierd going on with that Carb.. Do you have another available?
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St. Jude Donor '09-'11-'12-'13-'14
Thanks, Mike. I didn't think it would, but it's been years since I messed with this stuff and my oldtimer's disease kicks in when I least expect it.
The pop is likely coming from the too rich condition fouling the plugs, I guess.
The pop is likely coming from the too rich condition fouling the plugs, I guess.
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St. Jude Donor '09-'11-'12-'13-'14
Hey 67, I went through that routine already and all appears OK. I think it's maybe the carb after all. Don't have another Demon so maybe I'll drop an AFB on it and see. At least I can change the jets in those without making a mess!
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From: Washington Michigan
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St. Jude Donor '09-'11-'12-'13-'14
Hi John, thanks for the comment.
I spoke with the Demon tech guy this morning and he told me that the initial timing needed to be 18 degrees and 10 wasn't enough. He also said to go up to Autolite 3924 from 3923 which were installed. I have a friend locally who's running 68/72, but the motor is a bit different than mine. I'll give your numbers a shot after I try the plug change and timing bump. I just hate taking the carb apart so I'll do about anything to keep from it. AFB's are so much easier
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St. Jude Donor '09-'11-'12-'13-'14
I hate this weather, it makes me nuts. C'mon Spring!
Burning Brakes
Joined: Aug 2001
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From: Frederick Md
Small steps!
Hi John, thanks for the comment. I spoke with the Demon tech guy this morning and he told me that the initial timing needed to be 18 degrees and 10 wasn't enough. He also said to go up to Autolite 3924 from 3923 which were installed. I have a friend locally who's running 68/72, but the motor is a bit different than mine. I'll give your numbers a shot after I try the plug change and timing bump. I just hate taking the carb apart so I'll do about anything to keep from it. AFB's are so much easier
I spoke with the Demon tech guy this morning and he told me that the initial timing needed to be 18 degrees and 10 wasn't enough. He also said to go up to Autolite 3924 from 3923 which were installed. I have a friend locally who's running 68/72, but the motor is a bit different than mine. I'll give your numbers a shot after I try the plug change and timing bump. I just hate taking the carb apart so I'll do about anything to keep from it. AFB's are so much easier
Drifting
Joined: Apr 2007
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From: Carson City Nevada
Hey Dave, been like you...holed up waiting for spring...working on the car, screwing it up, you know, those kinds of things. Decided against BB (for now). Changed every nut and bolt and hose and wire I could get to this winter. Can't seem to get rid of a new ignition miss that I didn't have before...put on new plug wires...thinking that's where the problem is. Planning on doing a show this weekend (at CC Harley Davidson), hope I can figure it out before then. I'll drop in one of these days when you're not to busy. Nick
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St. Jude Donor '09-'11-'12-'13-'14
Just from my own history, I find it much better to make small steps, change one thing at a time so you don't get so far off the chart. I don't know about all that timing, sounds a bit strange to me but what do I know. I think John is right about the jets. One other thaing, what squiters do you have in the primary???? I've had issues with pump shot that caused a little lag problem.
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From: PARADISE
St. Jude Donor '09-'11-'12-'13-'14
Hey Dave, been like you...holed up waiting for spring...working on the car, screwing it up, you know, those kinds of things. Decided against BB (for now). Changed every nut and bolt and hose and wire I could get to this winter. Can't seem to get rid of a new ignition miss that I didn't have before...put on new plug wires...thinking that's where the problem is. Planning on doing a show this weekend (at CC Harley Davidson), hope I can figure it out before then. I'll drop in one of these days when you're not to busy. Nick
Next thing you know you'll be riding a Harley
. Don't get to close to any of those mamas this weekend. Give a call sometime, you're always welcome to come by.
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St. Jude Donor '09-'11-'12-'13-'14
Guess I'll just go down on the jets until it melts
Melting Slicks
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From: St Louis MO
Which ignition system are you using? Are you sure it's 100%? Like old times say, "Most carb problems are caused by ignition!"
Also, you might verify that the TDC marks on your harmonic damper really indicate TDC... with a modified engine and two different timing tag locations, this might be the source of your problem.
Also, you might verify that the TDC marks on your harmonic damper really indicate TDC... with a modified engine and two different timing tag locations, this might be the source of your problem.
Team Owner
Joined: Mar 2003
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From: Greenville, Indiana
At your alititude, I'd try #68 in the primary. Then work on the secondary. That popping and banging out the exhaust sounds like raw gas being burned in the exhaust because of a fouled plug somewhere.
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St. Jude Donor '09-'11-'12-'13-'14
Which ignition system are you using? Are you sure it's 100%? Like old times say, "Most carb problems are caused by ignition!"
Also, you might verify that the TDC marks on your harmonic damper really indicate TDC... with a modified engine and two different timing tag locations, this might be the source of your problem.
Also, you might verify that the TDC marks on your harmonic damper really indicate TDC... with a modified engine and two different timing tag locations, this might be the source of your problem.
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St. Jude Donor '09-'11-'12-'13-'14
It quit popping after I changed the plugs so you are likely correct. The 74 in the primary is still way too rich, I agree. Fixing that later today.
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St. Jude Donor '09-'11-'12-'13-'14
Finally getting somewhere. 70's and 76's seem to be pretty good for now, but just a tad rich. OK for the new engine I think. Just a hint of black smoke when it sits at idle for awhile then punch it. Idles down better now and takes the throttle a lot better. I backed the timing down to 12 and it wasn't happy, but at 15 it is. I'll leave it alone for the time being.
Thanks for all the help, it is much appreciated
Thanks for all the help, it is much appreciated
Last edited by claysmoker; Apr 15, 2009 at 09:48 PM.