Timing too advanced |
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Timing too advanced |
familienauto |
Aug 12 2010, 05:05 PM
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#1
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Volksporsche Group: Members Posts: 136 Joined: 5-November 06 From: UW Seattle Member No.: 7,156 Region Association: Pacific Northwest |
73 1.7 D-jet, vacuum advance stock distributor.
First time I have set the timing on this car myself, but used to doing it on VWs with Type I and IV engines. The fan has two marks, a "0" for TDC, and a red notch for 27 BTDC. Distributor vacuum hoses removed and plugged. Even with the distributor turned as far clockwise as it will go, the timing is (according to the marks on the fan) at least 10-15 degrees too advanced at 3500 RPM. Is the logical explanation that the fan was somehow installed incorrectly? The car was running fine, I pulled the distributor to clean the trigger points. I marked how it was lined up before, so I'm tempted to just put it back, but this is a little unnerving. |
realred914 |
Aug 13 2010, 12:29 AM
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#2
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Senior Member Group: Retired Members Posts: 1,086 Joined: 1-April 10 From: california Member No.: 11,541 Region Association: None |
could be the distributor drive gear is not in the right mesh, it htta is off, the dizzie may not be able to rotate to the right postion to get the timing right (the vacuum can will hit the fan house) les assume the fan marks are right for now, (fan can't be installed wrong, only fits one way) although different fans may have different timing marks, TDC shoudl be the same.
now find the actual #1 TDC (ie piston one at full out postion, and both valves for #1 closed (remove valve cover to confirm valves closed) remeber that the crank turns twice for a complete cycle, so there are two postion for which the TDC mark is stright up , but only one of them is for #1 piston TDC (valve closed) the other time the mark is on top, the #1 vlaves are NOT closed. now that you have confirmed your motor is realy at #1 TDC, you have to look at the rotor postion in the dizzie and see which way it points, with teh vasccum can near the oil filler, and the trigger point plug near the fan house, the rotor should line up with the number 1 plug contact on the cap. (also a small notch on the dizzies body on the edge teh cap sits on. if this is not the case, then teh distributor dirve gear is not indexed correctly and that may prevent you from being able to set the timing. go thru the distribiutor drive gear installation procedure found in many repair manuals for the 914 and that shoudl get our dizzie where it should be. good luck |
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