View Full Version : TR4/4A TR4 Timing and Distributor Gear

11-10-2008, 10:48 AM
I'm almost ready to "button up" my distributor after installing a new timing chain and tensioner. I've dropped the distributor gear down onto the cam gear and lower distributor bush. I'm looking for the classic offset angle where the slot in the gear points to Pushrod Tube No. 1. I can get it just a bit before and a little bit after, but at TDC it doesn't seem to be pointing dead on.

Is this typical? I'm fairly certain I lined the crank and timing sprockets correctly, and valves 7 and 8 seem in balance. I'm definitely at TDC. Should I suspect I'm off on the cam sprocket by a notch, or is the angle of the slot not all that precise. If I drew a straight line I'd be off the center of the Tube No. 1 by 1/4 inch to 3/8 inch.


11-10-2008, 02:16 PM
I have not done it for awhile, but it sounds like you have something wrong perhaps just a little. If you lined up the marks right on the sprockets that should be fine and make sure you are at TDC with the compression stroke. Look at the valves and see that number one valves are closed when the mark on the pull hits the stationary mark on the timing chain cover. Or Pull number one plug and put your thumb over the hole and turn the engines over and when it pushes your thumb off that is TDC compression stroke. If I remember right, the drive gear only fits in the oil pump one way for it to truly bottom out in its hole, and I think it pretty much points the rotor right to the push rod. The drive gear slides and turns as it goes in also and you might have to get a long screw driver and move the oil pump slot a little to accommodate the slid. Anyways try and start it to see what happens.

11-10-2008, 03:04 PM
If I'm not mistaken (and PLEASE correct me if I'm wrong) if the dots are lined up on the timing chain gears, you're on the #4 TDC, not #1. Turn the engine one full revolution and THEN drop in the distributor drive gear.

11-10-2008, 04:50 PM
I believe the "pointing towards #1 pushrod tube" is only approximate; so no harm done if it points a little in front of the tube.

If valves 7 & 8 are on balance (and you have a stock or factory performance grind cam); then the cam is at it's TDC position even if you've installed the chain wrong.