Timing too advanced Options

[familienauto]

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]

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

[VaccaRabite]

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.
good luck

(IMG:style_emoticons/default/agree.gif)

But, first things first. Are you absolutely positive that you know what cylinder is cylinder #1?
Looking from the back bumper towards the nose the cylinder are as follows:

cyl2 cyl4
cyl1 cyl3

Using the actual Cyl1? Yeah, I thought you probably were. Onward! Remove all the spark plugs, and spin the engine by hand to bring the #1 clyinder to TDC. Here is an easy way to do it.

Jack the car up. on one side so that one rear wheel is off the ground, but one rear wheel is on the ground. You want the rear wheel nearest to the #1 cylinder to be on the ground. Put the car in 5th gear. You can now spin the wheel in the air and move the engine.

Have a helper turn the rear wheel while you are over the motor. Using a drinking straw (NOT A CHOPSTICK!) down the spark plug hole you will be able to feel the piston advance up and start to contract again. Get the piston to the very top of its arc.

Now, since the piston hits the top of its arc twice during the firing sequence, you need to confirm that you are actually at TDC, and not at the top of the exhaust stroke. the easiest way to do that is to look at the valves. if both valves are closed you are at TDC. If the outside valve is open, you are on the exhaust stroke and 180 degrees off TDC.

When you find TDC, use your inspection mirror to find the timing notch. You may need to turn the motor a degree or two in either direction to find it, but it should be quickly visible. If you are at TDC, but can not find the timing mark, you know that the fan has become unindexed, and can not be trusted. The most likely situation is that the fan was installed improperly. Another possibility is that the key on the crank hub has sheared off (uncommon, but it can happen) and the fan hub has rotated.

ANOTHER possibility, is that you are using the timing gun wrong. depending on the type of gun that you have, you either set timing off the red mark, or off the TDC mark. If you are using an old school, non adjustable gun, you set your timing off the 27 degree mark.

BUT. Some new guns don't work like that. Lots of guns now have a dial on them that you set to the amount of advance that you want. When using this type of gun, you use the TDC mark. So if you have a new gun, and the dial has been nudged to 10 degrees advance, if you start flashing the 27degree mark, you will never hit it. You can use a new gun with a dial the old fashioned way by making SURE the dial is set to Zero.

Yeah, I'm a total dick for giving you the easiest possible solution last after writing a small book. I'll be able to sleep tonight anyhow. :-)

Good luck,
Zach