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| mcericmc |
Jan 15 2026, 12:25 PM
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#1
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Newbie ![]() Group: Members Posts: 5 Joined: 30-June 21 From: Texas Member No.: 25,681 Region Association: None |
There is only one timing mark on my 1.8 fan. It's visible through a notch on the rear side of the fan via the inspection port. Pelican parts info says the mark is TDC. Auto Atlanta says it's 7.5 degrees BTDC in the 914 tech tips 700 book. Can someone please tell me which is correct? I need to make sure the timing and valves are adjusted properly. (IMG:style_emoticons/default/WTF.gif)
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| 930cabman |
Jan 15 2026, 01:56 PM
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#2
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 4,450 Joined: 12-November 20 From: Buffalo Member No.: 24,877 Region Association: North East States
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(IMG:style_emoticons/default/welcome.png)
wish I could be of assistance, but I have never seen only one timing mark (IMG:style_emoticons/default/screwy.gif) |
| Jack Standz |
Jan 15 2026, 02:04 PM
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#3
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Senior Member ![]() ![]() ![]() Group: Members Posts: 665 Joined: 15-November 19 From: Happy Place (& surrounding area) Member No.: 23,644 Region Association: None
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Photo
Attached image(s)
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| wonkipop |
Jan 15 2026, 04:08 PM
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#4
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914 Guru ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 5,343 Joined: 6-May 20 From: north antarctica Member No.: 24,231 Region Association: NineFourteenerVille
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Photo thats a D Jet fan - its different to the L jet 1.8 @mcericmc - the timing mark on the 1.8 fan is the 7.5 before TDC. its the only mark if its an orig fan. i think pelican parts may have confused their info with the D jet engines. which do have a TDC mark on the fan (as well as several others). |
| mcericmc |
Jan 15 2026, 04:47 PM
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#5
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Newbie ![]() Group: Members Posts: 5 Joined: 30-June 21 From: Texas Member No.: 25,681 Region Association: None |
Thanks. I think your right. What REALLY confused me is the photo Pelican Parts put on the internet of the template inside the hole showing the mark in the notch on the fan to be TDC.
From everything I've read, the mark on the fan should actually be at the arrow on the template at 7.5 degrees BTDC. Once I got that figured out, I was able to use the template to put a mark for TDC a little more than 1/2 inch to the right. That picture really had me pulling my hair out. (IMG:style_emoticons/default/sad.gif) |
| emerygt350 |
Jan 15 2026, 04:51 PM
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#6
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 3,447 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
I would always establish tdc regardless of what the pictures say. Never know if it is the original fan unless it was yours new.
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| Jack Standz |
Jan 15 2026, 06:38 PM
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#7
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Senior Member ![]() ![]() ![]() Group: Members Posts: 665 Joined: 15-November 19 From: Happy Place (& surrounding area) Member No.: 23,644 Region Association: None
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Ok, here's a follow-up to my previous attempt to post information on how to figure out where Top Dead Center (TDC) for cylinder #1 is on your motor. Please note that when timing the motor it is important to understand the difference between TDC when cylinder #1 is on its compression stroke versus the exhaust stroke.
You only need the TDC fan marking for valve adjustments and ignition timing. Any other marks on the fan or flywheel aren't needed. It doesn't matter if it's an ljet fan, djet fan, a bus fan, a 411/412 fan, etc. Take a marker, white paint or even a crayon. If there isn't a mark there already, put a mark in the middle of fin #6 and fin #7 (TDC is actually a tiny bit closer to fin #6 than fin #7, if that matters to you). That's close enough to TDC for #1 cylinder to perform valve adjustments and set your timing. Even though a standard timing light can be used, strongly encourage using a dial back timing Iight. Additional instructions start at the third post: https://www.thesamba.com/vw/forum/viewtopic.php?t=699839 |
| Ninja |
Jan 15 2026, 07:58 PM
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#8
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Member ![]() ![]() Group: Members Posts: 69 Joined: 25-September 25 From: Granbury Texas Member No.: 29,004 Region Association: Southwest Region |
Just adding verification...
I too, was perplexed by the no TDC and no 27 degree mark on my 75 914 1.8L A swap to a 2.0l balancer is how I fixed mine... Important to make a second TDC mark 180 degrees from the original. Make it a different color (mine's blue). This will allow accurate TDC settings for leak down testing on all cylinders. IMO it seems silly that Porsche changed the harmonic balance markings just because of L-Jet. Jack's method will work fine. If you want to "fine tune" the TDC marks here's an accuracy test. Remove plugs and do a leak down test with #1 at TDC compression. If you are within 1/2 a degree of perfect adding the leak tester will NOT cause the engine to rotate. If you are outside this range the engine will rotate 180 degrees SO FAST it's hard to see it... (IMG:style_emoticons/default/ninja.gif) Watch which direction it turns and cheat it a tiny bit in the opposite direction until the LD tester doesn't flip it over. |
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