I tried to check the timing on my 1993 4.9l last night with no success. Couldn't find the timing mark on the damper. Manually rotating the engine with a ratchet I finally found a notch, about 1/8 inch wide, machined into the lip at the rear of the harmonic damper. Assuming that's the TDC mark, I painted a white stripe next to it to make it easier to see. Started the engine again and looked all over with the timing light for that mark, finally found it smack at the bottom of the damper! That's at 6:00 o'clock looking at the front of the engine. What the heck? I assume the outer shell of the damper has spun on its hub. Is this a realistic possibility?

There are two possible locations on the timing gear cover for checking the timing. Looking at the front of the engine, one location is a bolt-on degree indicator at about 10:30. The other is a group of degree marks cast into the timing gear cover at about 1:30. Which one of these sets of marks is the proper one to use, assuming the TDC mark on the damper is returned to its proper orientation?

Regards,
Bob P.

 

Bob, you want to use the set of marks on the left at about 10:30 as you describe it. It's not fun, but if you can't read degree numbers next to these marks its best to crawl under with a toothbrush or similar brush and clean around the marks so you can see the degree numbers. Next you have to pull the spout plug before you start it to check the base timing with a timing light. On my 90 F150 the spout plug is just to the right and slightly above the distributor (standing at the radiator and looking under the hood). Looks like a square electrical plug that is grey, attached to wires coming out of right side of dist. Yours may be somewhere's else. If you have a manual check it for location if the plug isn't readily visible. Check timing with spout plug pulled. It should be 10 degrees BTDC...that's base timing for most 4.9's. If not, you'll have to loosen the dist. bolt (another fun job, be careful, you can lose skin and knuckles on this one) a bit and rotate it slightly until you are at 10 degrees, then lock it back down. I think your timing indicator may have slipped as you said, could have happened if the timing gear/cover were changed in the past. Mine sits at the 10:30 position and the base timing notch-indicator is noticably longer than the rest. If your marks at 10:30 aren't numbered, count them and post back, and I'll check mine to see how they are numbered and post or email that to you.

 

Thanks for the response. I'm glad to know which set of timing marks is the correct one.

Now if I can figure out what's going on with the damper I'd be set. As it is, with the SPOUT connector removed, the timing light finds the mark on the damper about 120 degrees before top dead center! Obviously that can't be right, the truck runs great and gets 17 mpg, so the next task will be to determine where the timing mark on the damper is located when #1 piston is at top dead center. I'll try that tonight and let you know.

Regards,
Bob P.

 

Bob ,
The Timing Mark for your engine is very hard to see , it is only a tiny indentation / slit . I had to paint a white mark across the balancer to see it with the timing light . Unless you have removed the distributor or done something else to change the timing , Im betting it is still on 10 Deg BTDC .The 300 uses gears on the crank and on the cam so there is very little play and wear as opposed to a timing chain . Once you find the mark on the balancer , do as Tim described in the above post concerning the SPOUT connector .
Paul

 

Thanks, guys, for the responses. I found the REAL timing mark on the damper, wire-brushed it, and painted it white. When I re-checked with the timing light, all was well!

Thanks again for the help!

Regards,
Bob P.