View Full Version : TR4/4A TR4 ignition timing

05-22-2005, 09:45 PM
I just purchased a 65 TR4 that hasn't been running for several years. Prior to being stored, the head had been rebuilt and replaced (hopefully timing chain replaced correctly). After doing all the things you need to do to start an engine after a long storage, I fired it up. It started almost immediately and after a little fine tuning stayed running for me to drive it, but it really doesn't run smoothly, so I'm attempting to adjust all the needed settings. The problem is, setting the ignition timing correctly. I can get the timing hole lined up with the marker, but the #1 piston does not seem to be at TDC and the distributor rotor is slightly off the #1 plug hole. If I move the crank about 1/4 turn further, the piston reaches TDC and the rotor lines up perfect with the #1 plug hole. Is this normal and should I just paint another mark on the crank pulley and adjust it to that mark. Also, how do I figure out the advance degrees to set it at. If anyone can help me I'd greatly appreciate it. /ubbthreads/images/graemlins/confused.gif

Geo Hahn
05-22-2005, 11:22 PM
Is this normal

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...should I just paint another mark on the crank pulley and adjust it to that mark.

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That should work. For advance try about 3/8" on the crank pulley (using your new mark). That's close enough to 5 degress that you should be able to dial it in from there.

05-23-2005, 12:18 AM
I have two suggestions here:

First, let's assume the hole is correct. The rotor always looks a little different than the manual says. I'm not saying it's right on your car, but I'd suspect that only after you're certain you correctly tuned the car.

Make sure you performed a static timing like the manual says. I'm sure you must know the drill.

If not, just use a wire and light bulb. That's what the old Chilton and other manuals recommend. You can use your turn signal bulbs if you don't have an extra one.

Do this only after you've properly set the point gap with a feeler gauge--carefully.

Pull the crank toward you until the marker is lined up with the hole. Then, with the ignition key turned on, and with a wire connected to the bulb, coil and ground, all at the same time (I usually touch the bottom of the bulb to the timing cover bolt, one end of the wire to the bulb housing and the other to the connector on the distributor side of the coil), rotate the distributor until the points just "open," meaning the bulb lights up. The bulb should just come on. Now tighten the distributor up so it won't rotate. Then, to get 4 degrees BTDC, use the adjusment dial on the distributor. Your manual should explain all of this, and the distributor shows you which way to turn the dial to advance or retard.

Static timing is best, and after you're done you can check it with a timing light if you really want to, but that shouldn't be necessary.

OK, that's my first suggestion. Proper point gap and timing.

My second is to make darn certain you have four good plugs, a good distributor cap and, most importantly for rough running, good plug wires and no "shorting out." Make sure none of the rear boots on the plugs are too close to any metal, such as the fuel line or any other steel. I've seen that be a problem due to the design of the fuel lines and other equipment on TRs. Bad wires or "arcing" from the plugs will ruin a car's performance.

Good luck.

05-23-2005, 11:55 PM
My mark on the pulley is off 180 degrees so I have to time using the static method and the car runs great. By chance, the pulley has a fracture so I have to change it which will let me get the timing mark corrected. From what I can see, the timing mark should set opposite from the key on the crank. Nothing in the manual to tell where it goes when reassembling.

05-24-2005, 08:26 AM
Thanks for the replies. I'm going to try and set the timing at the mark I made with the piston at TDC and the rotor inline with the #1 plug. I purchased a advanced unit off of ebay and won't be able to see if this setup works until I can replace the old advance(it wouldn't move at all, finally broke it after 2 days of trying to move it). I'm sure that was also part of the problem. Anyways, thanks again. I'll let you know how it turns out.

Webb Sledge
05-24-2005, 06:48 PM
Are you sure the distrubutor gear isn't 180 degrees out? The car will run with it out that much, but it will act a bit wierd. I made that mistake on my car. Easy fix though.

05-25-2005, 09:11 AM
Assuming valves and point gap are set correctly, here's what I do (and it has always worked well for me)... Time for maximum RPM with engine at fast idle (1500-1800 RPM), note the RPM, then retard the timing until the engine speed drops approximately 100 RPM. That should get you in the ball park. Next, drive it, and listen for pinging during acceleration in third or fourth gear. If you don't hear any pinging, advance the timing until you hear slight pinging, then retard slightly. If you hear pinging, retard the timing in small increments until it goes away.

Because of the unpredictable operation of the centrifugal and vacuum advance mechanisms on the TR4, I don't think it's possible to time them with a timing light.