 Timing, By hand? |
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| Boothy |
 Jun 25 2026, 09:36 AM
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#1
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Member  Group: Members Posts: 111 Joined: 17-January 19 From: Abington, MA Member No.: 22,805 Region Association: North East States  |
Greetings all!
I haven't bothered you guys in over a year I think -you're welcome. Last fall the new engine started smoking and the tail pipes were black. Sluggish. I think I rejetted at some point but can't recall. Naturally I assumed I burned something up or broke a ring etc. so I put it under a cover for the winter. Bought a compression tester but I was so fed up I just said screw it till spring. Refreshed and ready to look at it again, I looked online thinking I'll start with jetting. I have Weber 40s on a 1.7 punched out to 2.0. I was at 185 mains but another AI search (I know I'll hear about that) said go to 1.15 mains and 2.00 air correction. Seemed to cleanup last night and I'll run it some more today. But now it pops a little on deceleration. Sounds better -cleaner. Looking the popping might be a too lean condition, air leak near the exhaust flange, etc. BUT, I had a lot of trouble with the timing mark on the fan so I'm not 100% sure I have it where it's supposed to be. Despite multiple efforts (looking at lots of pictures of the fan marks) I'm just not sure. I know it sounds hack but I'm wondering if I can advance the 123 distributor a little at a time manually. I'll do a compression test tomorrow to be sure but thought I'd throw it out to the gods. Thanks in advance! |
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| emerygt350 |
Jun 25 2026, 10:03 AM
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#2
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Advanced Member Group: Members Posts: 3,649 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
Did you test the compression?
I time mine off the mark on the flywheel. If you have carbs that will be easier than using the fan and no questions about what you are looking at. It is tdc for 1. Just look at the flywheel at the top rear engine window and align the mark with the case halves seam. |
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| brant |
Jun 25 2026, 10:51 AM
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#3
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914 Wizard Group: Members Posts: 12,220 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains 
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You have to have the timing correct first before you can tune the carbs
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| Superhawk996 |
Jun 25 2026, 12:01 PM
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#4
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914 Guru Group: Members Posts: 7,916 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch
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QUOTE(brant @ Jun 25 2026, 12:51 PM)  You have to have the timing correct first before you can tune the carbs (IMG:style_emoticons/default/agree.gif) x 10 |
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| Boothy |
Jun 25 2026, 12:17 PM
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#5
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Member Group: Members Posts: 111 Joined: 17-January 19 From: Abington, MA Member No.: 22,805 Region Association: North East States |
Okay. Thank you. Forgot about the flywheel. What about advance?
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| BillC |
Jun 25 2026, 12:54 PM
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#6
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Senior Member Group: Members Posts: 738 Joined: 24-April 15 From: Silver Spring, MD Member No.: 18,667 Region Association: MidAtlantic Region
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QUOTE(Boothy @ Jun 25 2026, 02:17 PM) Okay. Thank you. Forgot about the flywheel. What about advance? Easiest way is to buy or borrow a timing light with built-in advance offset. That way, you set the timing light to the desired advance value (I think stock is 27degrees) and adjust the distributor until the flywheel mark lines up with the case. |
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| emerygt350 |
Jun 25 2026, 01:07 PM
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#7
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Advanced Member Group: Members Posts: 3,649 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
Since you have a 123 you need to set it up as the directions describe then go from there. If you were questioning your marks when you were setting it up it might be worth double checking with the flywheel to verify it is set correctly. Bluetooth or non-bluetooth 123? Timing greatly affects vacuum, and vacuum greatly affects the carb tune so you need to feel good about your timing before you play with the carb.
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| Boothy |
Jun 25 2026, 01:17 PM
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#8
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Member Group: Members Posts: 111 Joined: 17-January 19 From: Abington, MA Member No.: 22,805 Region Association: North East States |
The 123 is not Bluetooth but I set it up as directed.
I'll let some moths out and get the better timing light. Thanks for all the help!!!! |
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