Just tuned up my 4.9 with new plugs, cap, rotor and wired. Had to replace the distributor as well. Am at TDC with the #1 cylinder in the compression stroke, thew rotor pointing at the #1 terminal on the cap. The timing mark groove is at 7 o'clock and will not line up with the TDC timing marks no matter how many times I take it around. Any suggestions? Could the previous owner have re,oved the damper pulley and gotten it back on wrong? I thought there was a keyway to prevent this but I could be mistaken. I am at a loss - needless to say I have the front torn down to the timing chain cover in case I need to check the alignment of the gears but it isn't my idea of a good time. Help please!

 

Was it timed properly BEFORE you did all this work? If so, previous owner probably did not do anything wrong and instead you did something wrong. If not, then visa versa. I have never timed a 4.9 so I can't give any step by step instructions.

 

Sounds like either the engine isn't really on TDC or the damper has slipped. Did the truck run after the part replacment session?

 

I have no idea if the truck was properly timed prior to my replacement session but it did run but not great due to old plugs, etc. It did run afterwards for a minute or so but stalled out and wouldn't re-start. Checked the fuel and it's getting fuel. Went back to the drawing board via the manual and re-set the distributor to the same markings as the old that I pulled out with the exception of setting the number 1 cylinder to the top of the compression stroke and re-checking the location of the rotor in reference to the #1 terminal. I've never heard of the damper slipping but I am open to suggestions. I appreciate the answer.

 

What I would do if in doubt regarding something like this is remove the valve cover and locate the valves for cylinder #1. The dampener will tell you top dead center, but it wont tell you if it's power or compression....but the valves will. Get to TDC as per the dampener and look at the valves. If the valves correspond with what the dampener is telling you then all is well with the installation of the dampener. If the valves and the dampener do not correspond then you have a problem.

 

Actually the dampener pulley groove for TDC is sitting at the bottom (about 7am) when the piston and rotor are lined up - this is what is driving me crazy. Thanks for your answer

 

OK, well do what I said and that will tell you first of all if you are really on compression stroke and secondly if the valves and the dampener correspond. If this checks out good then you know that you are doing something wrong.

 

Terry,

The dampener pulley slips on some of the older trucks due to the insulater material gets old and timing mark becomes inaccurate. Find TDC with the #1 cylinder in the compression stroke, get the rotor pointing at the #1 terminal on the cap, like you did, and disconnect the SPOUT plug from the harness going to the distibutor, this allows you to set the base timing without the computer involved. Set the timing by ear and listen for the lifters start to chatter and back it off some till it sounds good. Lock it down, reconnect the SPOUT plug and then disconnect the - neg battery for 15 minutes to let everything reset, then take it for drive. I had the same problem on my F150, the timing mark was at about 7:00 also and I couldn't get it anywhere near the scale on the timing case cover. Setting by ear works pretty good in this case and my truck runs great. Not much else you can do except get a new dampener pulley.
If anybody has a better idea for a quick fix on this, chime in as that's what the Forum is for.
Good luck and let us know how it tuns out.

Johnny


1988 Ford F150 Custom 4.9L 4 speed glaspack w/dual exhast alloy Fordwheels
1990 Ford Mustang LX 5.0 AOD hatchback BBK H pipe w/Flowmasters
1993 Ford Mustang LX Coupe 5 speed


.....................................God Bless Henry Ford.......................................


Ford F 150's Rule the Road

 

Johnny


Thanks for your help. Much appreciated! Terry

 

Thank You Johnny! I ran into a Ford mechanic as well as another 4.9 owner, both of whom said, and experienced (without question) that the Dampener Pulley (Harmonic) most definetly has a habit of slipping when old and worn. Napa carries them (approximately $109.00). Will try this fix and see how it goes.

Thanks again for everyones help - love reading the different threads.