Timing marks |
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Timing marks |
aeginc77 |
Aug 11 2023, 04:37 PM
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#1
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Newbie Group: Members Posts: 19 Joined: 29-April 15 From: United States Member No.: 18,682 Region Association: None |
I recently installed an electronic ignition replacing the point and condensoer. Now I want to check the timing but I can't find any timing marks on the fan! I see the notch in the housing but even when I align the rotor to the #1 lead and look at the fan I cannot see any timing marks not the TDC mark never mind the 27.5 before TDC. Has anyone run across this and what is the solution?
Thanks |
Jack Standz |
Aug 11 2023, 05:20 PM
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#2
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Member Group: Members Posts: 279 Joined: 15-November 19 From: Happy Place (& surrounding area) Member No.: 23,644 Region Association: None |
How did you set the timing before?? Just wondering.
Put the motor at TDC on #1's compression stroke (one way is with a borescope through the spark plug hole). Get a white paint pen and mark the fan at the vnotch inside the fan housing area. Get a "dial back" timing light to set the timing (read instructions (IMG:style_emoticons/default/smile.gif)). Best wishes for a successful fix! |
emerygt350 |
Aug 11 2023, 06:28 PM
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#3
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Advanced Member Group: Members Posts: 2,132 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
The mark is on the wrong side, you need a mirror to find it. When you do, just mark the side you can see.
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Jack Standz |
Aug 11 2023, 10:27 PM
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#4
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Member Group: Members Posts: 279 Joined: 15-November 19 From: Happy Place (& surrounding area) Member No.: 23,644 Region Association: None |
Good point, sometimes you can catch a view of the timing mark(s) with a mirror from the other side of the fan housing.
Also, some flywheels may have TDC marked too but this may require pulling the rear engine tin slightly out of position or viewing from below the car. Actually, some people prefer marking the flywheel & will mark TDC and 180 degrees out for such things as valve adjustment procedures (can tell where the camshaft is supposedto be without crawling out from under the car. |
aeginc77 |
Aug 12 2023, 07:03 AM
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#5
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Newbie Group: Members Posts: 19 Joined: 29-April 15 From: United States Member No.: 18,682 Region Association: None |
Good point, sometimes you can catch a view of the timing mark(s) with a mirror from the other side of the fan housing. Also, some flywheels may have TDC marked too but this may require pulling the rear engine tin slightly out of position or viewing from below the car. Actually, some people prefer marking the flywheel & will mark TDC and 180 degrees out for such things as valve adjustment procedures (can tell where the camshaft is supposedto be without crawling out from under the car. Thanks for the suggestions but my 914 looks like it has a cast aluminum fan casing. There is no tin work to remove at least while the engine is in the car! There are two very clear timing marks both way off so far off that if I line up the TDC mark with the v notch the rotor point halfway between leads to cylinders 3 and 4! I think I am faced with gettin gunder the car with mirror and searching for mark on top of transmission which from the descriptions I have read seems like a virtually impossible task! |
dr914@autoatlanta.com |
Aug 12 2023, 10:45 AM
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#6
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914 Guru Group: Members Posts: 7,887 Joined: 3-January 07 From: atlanta georgia Member No.: 7,418 Region Association: None |
there is a good picture of the fans with factory marked timing notches in the 914 "tech tips 700"
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914sgofast2 |
Aug 12 2023, 12:22 PM
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#7
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Senior Member Group: Members Posts: 622 Joined: 10-May 13 From: El Dorado Hills, CA Member No.: 15,855 Region Association: None |
I think the Pelican Parts website has an article about timing marks in its technical subsection. The early cars had three (3) timing marks for TDC, 8 degrees static, and full advance at 2800rpm with vacuum hoses disconnected and plugged. Some engines only had one timing mark; I have a cooling fan from a 1.8 liter like that.
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aeginc77 |
Aug 12 2023, 12:55 PM
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#8
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Newbie Group: Members Posts: 19 Joined: 29-April 15 From: United States Member No.: 18,682 Region Association: None |
I think the Pelican Parts website has an article about timing marks in its technical subsection. The early cars had three (3) timing marks for TDC, 8 degrees static, and full advance at 2800rpm with vacuum hoses disconnected and plugged. Some engines only had one timing mark; I have a cooling fan from a 1.8 liter like that. I have seen pictures of the marks....I have several - all wrong. lol. I say this because when the rotor is pointing at or near the #1 lead there are no timing marks showing or even close! The car actually drives well but I really wanted to actually see how it was timed. Pelican does have a good article about finding TDC by looking at top of transmission with a mirror. I think I'll leave it to my local shop to find and mark the actual timing marks.....with indelible paint! |
Jack Standz |
Aug 12 2023, 02:13 PM
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#9
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Member Group: Members Posts: 279 Joined: 15-November 19 From: Happy Place (& surrounding area) Member No.: 23,644 Region Association: None |
Good point, sometimes you can catch a view of the timing mark(s) with a mirror from the other side of the fan housing. Also, some flywheels may have TDC marked too but this may require pulling the rear engine tin slightly out of position or viewing from below the car. Actually, some people prefer marking the flywheel & will mark TDC and 180 degrees out for such things as valve adjustment procedures (can tell where the camshaft is supposedto be without crawling out from under the car. Thanks for the suggestions but my 914 looks like it has a cast aluminum fan casing. There is no tin work to remove at least while the engine is in the car! There are two very clear timing marks both way off so far off that if I line up the TDC mark with the v notch the rotor point halfway between leads to cylinders 3 and 4! I think I am faced with gettin gunder the car with mirror and searching for mark on top of transmission which from the descriptions I have read seems like a virtually impossible task! There is a tin piece at the rear top of the motor that you can push just enough (without removing) to see the flywheel. See attached photo. It's at the "12 o'clock position of the flywheel". Much easier than trying from under the car with a mirror. Never mind, just stick with marking the fan. Also, your distributor drive may be installed incorrectly. So, the suggestion is to find and mark TDC on #1 compression stroke, then use a dial back timing light. Attached image(s) |
Mark Henry |
Aug 13 2023, 08:15 AM
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#10
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
Try suggestions above, but if you still can't find any marks it could be a bus fan.
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930cabman |
Aug 13 2023, 08:23 AM
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#11
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Advanced Member Group: Members Posts: 3,130 Joined: 12-November 20 From: Buffalo Member No.: 24,877 Region Association: North East States |
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