Crazy timing, 27 degrees at idle Options

[Gcotton92203]

OK, I'm new to this forum stuff & have absolutely no idea what I'm doing but here goes. Just got a bad running 73 2.0 and found that the only actual problem was burnt and out of adjustment ignition points. I replaced them, dialed in the dwell at 45 and the car ran fine but of course I thought I should recheck the timing. I scratch marked the original position of the distributor before moving it. Vacuum hoses are disconnected and plugged. Can't get the idle below 1100 warm but it idles pretty smoothly so I don't see that as a problem. Here's the kicker. It's showing the timing as already 27 degrees advanced at "IDLE"???? If I set it a 27 degrees at 3500 it is so retarded it just dies at throttle down. So when I have it running & idling good, I have absolutely no idea what the timing and advance really is. The last thing I want to do is damage my engine from improper timing. Any help would be greatly appreciated. Thanks

[stugray]

How are you checking the advance?
With a variable timing light, or a static TL & the mark on the fan?

Some fans have a mark at 5 degrees BTC and 27 BTC.
Some might have a mark at 0 deg TDC.

If you look just behind the skinny enegine tin at the back of the engine, there is a transmission inspection hole where you can see the flywheel.
The FW will have a mark at TDC that lines up with the engine case split line at TDC.
This can help you figure out what mark you are trying to use up front.

I set my timing through the back and use a variable timing light.


If this doesnt help, the advance mechanism in your distributor might be stuck at full advance.

[McMark]

Yup, that's a pretty good summary.

[Gcotton92203]

Yup, that's a pretty good summary.

I can see the zero mark in the fan and about 2 inches away is the 27degree mark. I haven't checked to see if I can find the flywheel mark. When I start the car I use a standard timing light, no adjustable advance. At idle with vacuum hoses disconnected & plugged it is already showing 27 degrees advanced. If I rev the engine the mark moves forward substantially and returns with throttle release so it appears the centrifugal advance is working properly. If I run the car in the 27 degrees at idle position it starts harder. idles higher but runs great. If I retard it a bit it starts better, idles better but has a flatter throttle response and not as peppy. My understanding is the zero mark should show at idle and the 27 degree mark at 3500 rpm. It appears as if the fan marks are 27 degrees off but I don't see how that's possible. I also find it hard to believe I'd be running at 54 degrees advance at 3500 rpm.

[McMark]

Perhaps your fan has spun on the crank. It's happened before. Confirm with the flywheel mark or by pulling the #1 spark plug and watching/feeling the piston to confirm TDC.

[Gcotton92203]

Perhaps your fan has spun on the crank. It's happened before. Confirm with the flywheel mark or by pulling the #1 spark plug and watching/feeling the piston to confirm TDC.

WOW! That can happen? I was a VW mechanic many years ago but never did any serious work on the Type 4 engine. I know on the Type 1 engine that was impossible without a broken crank or pulley because they were woodruff keyed. I'll check the flywheel mark as soon as it cools down a bit outside. Too hot out here in the desert right now, Thanks

[Java2570]

Type 4 has the woodruff key on the crank to locate the fan hub & cooling fan...the keys can
shear, it has happened. Two weeks ago, I noticed a light scraping sound coming from my engine.
Pulled it out and found the cooling fan was coming loose and contacting the fan shroud. Also, the
locating pin on the fan hub was broken off. My woodruff key was still intact though....

[r_towle]

The flywheel won't shear.
Check TDC via the rear inspection hole as suggested' then compare it to the fan and ignition rotor location.