GSL-SE Timing Question
 

I apologize in advance, I know this has been brought up a lot, but I still can't find the answer to my question. I want to check the timing first to correct a backfire and poor idle on my car, stock 1985 SE w/ 13b. The pulley is marked with a red and yellow dot. I am assuming the yellow is TDC with 0 degrees for leading ignition. The FSM shows the leading is 5 degrees advanced for the 13B. Does this mean the yellow dot on the pulley is at zero or 5 degrees? I know there is a mechanical advance of about 14 degrees at 3000 RPM plus the vacuum advance. So, if I just want to set the timing to factory specs, how do I do that? I'd like to disable the vacuum advance and check it at about 3000 RPM with a timing light. So, I'm thinking the pulley should be marked at about 19 degrees beyond the yellow dot. If the circumpherence is 360 mm, and each mm is one degree, then I should mark the pulley about 19mm beyond the yellow dot. While timing, I should expect this mark to line up with the pin on the engine cover. Right??? Or am I way off base. Thanks.

the GSL-SE pulley has two marks, one for leading at idle, and one for trailing at idle. the marks are actually at -5BTDC (L) and -20BTDC (T). there is no TDC mark, as you don't need it.

you are right that the pulley is 360mm, and 1mm = one degree. if you want to make marks, set the engine to one of the marks, before you take the pulley off, as it can be installed 4 ways.

set the timing at idle, and then verify the timing advance @3000rpm. if the cart for the advance is in distributor degrees, timing at the engine will be x2, as the distributor spins at half speed.

Was the pulley ever removed from the hub? I had a problem with this on a past build. Remove the cover between the engine and bell housing near the intake manifold. Look for the flat open spot on the flywheel edge. Ensure the thick flat part of the counterweight is flat with the spark plug side. Then verify that the timing marks on the pulley are close to the pointer. Once that is verified then stab the dizzy and set timing. It's the only way to verify that pulley is on the right way since there are 4 ways to put it on!

key slot should be pointed toward the 9'o clock position. the yellow mark will be naturally lined up with the pin on the timing cover....

I know the pulley is correct as I checked this when I put the engine in. When I put the distributor in, I put the pin on the yellow dot for TDC, lined up the mark on the distributor and put it in, tightened it down. The engine runs like this, but not really well. It doesn't idle like it should and backfires. I set the TPS per the FSM and adjusted the dash pot to bring down the idle. The air bleed screw is all the way in and cannot be adjusted further. To fix all the issues, I'd like to start with the timing, but with a bad idle I don't know how accurate it will be using the yellow mark.

sounds more like intake leaks, shouldn't have to put the idle screw all the way in....

I also had a problem with the Timing Marks reading incorrectly because when the water pump was replaced sometime in the past by the previous owner, the pulley had not been put on correctly.

Well, in the process of doing all this, a major backfire that sounded like a bomb, blew out my original GSL-SE muffler!! :banghead: Timing turned out to be fine, or nearly so, and I still have the backfire. Next I will be tracking down an air leak. I think it is on the intake gasket.

I've been trhing to figure out how to put my E-shaft pulley back on in the right orientation...I found and removed the inspection cover. Looked at the lip of the flywheel as I turned the E-shaft...There is a "lip" around most? or at least half of the circumference of the flywheel that extends towards the front of the car. It's not very thick, and in one area, the lip disappears for a bit, then comes back. Is this the "flat cut out"? BUT, there is also an area of this "lip" that extends towards the center of the flywheel and is flat. Here the lip isn't thin anymore, it extends down and then back to the outer edge...Or is THIS the "flat" part? If I line up this last mentioned spot with the top and center of the engine, it puts the yellow timing mark right on the spot in one of the four pulley positions. I'm not sure which "area" is the one I need to look for. And whichever of these two "areas" is the correct one for me to be looking at, it needs to face the spark plug side of the engine? The last thing I read aboot this, it was supposed to face the intake manifold. Need clarification! Thanks.

search under my SN as i posted the how to find tdc using stock flywheel including pictures

They thick flat spot of the flywheel is the counterweight, it needs to be straight up and down on the spark plug side of the engine. Then remove the 4 crank pulley bolts and line the marks up. To the indicator and put the bolts back in. That flat thin area of the flywheel will be on the intake/exhaust side.

Hope this helps clear things up.

I think that's what I did...Someday I'll have to get a light and check. Thanks for the help.