My truck (1990 ford F150, 4,9 strait six and 5 spd,140K on it) started surging real bad and no power, than wouldn't start. I changed the fuel filter still no go. So I pulled #1 plug to check for spark. NO spark! So I know the ICM mounted on the side of the distributor is a common problem. So I pulled the distributor in order to get those tiny screws out. I marked the location of #1 and the location on the side of the block and also at the base. Took ICM to Auto Zone, they tested it and it hard failed everytime. Bought a new one, Reinstalled everything but now I cant keep it running. I realize now I screwed up, by not putting #1 at TDC, than pulling the distributor. I've read so many different posts about setting the timing, I'm confussed. Two sets of timing marks, on the pulley and the block, compression and exhaust, plus my Haynes manual isn't accurate,on and on.

Can anyone explain the honest to goodness, easiest way to set up the timing? Thank you!

 

For future reference, there is a tool to get the small screws out of the module without removing the distributor. Its around $25 on the tool truck for the fancy one or about $7 at autozone for a basic one. Its more or less a thin wall 7/32" socket.

There is nothing wrong with marking and pulling the distributor without putting it on #1 tdc compression. But when you pull it that way you need to mark where the rotor is pointing since that is where it needs to point when it goes back in. There is no need to mark #1 terminal if you didn't point the rotor at it in the first place. You do need to mark position of the distributor case at the base or just make note of the case's position. If you don't pull distributors very often it would prob be best to mark it at the base. But you are past that point now.

No matter what method you use you will need to set/check the timing afterwards. There is more than one way to do this, but unless you have spent a lot of time working with engines a timing light will be the easiest and most accurate way. If you can't borrow one from somebody you can buy cheap ones for $20 or $25, or maybe the parts store has one as a loaner tool.

In fact you may have the timing close enough all you need to do is adjust it for the truck to run right, might be worth checking the timing with a light before you pull the distributor again.

The correct timing scale is the one on the passenger side of the engine for our trucks. It is a separate metal piece that bolts on with the timing gear cover and extends partway over the dampner.

The correct mark on the dampner is a faint scribe mark about a quarter inch long, looks like a light chisel mark more than anything else. It is not the large notch. I recently verified this when I had my engine out and on a stand. I replaced the cam and timing gears and I am very sure of this.

https://www.ford-trucks.com/forums/1075573-95-f-150-i-6-timing.html#post10469335

Post #8 on the page I linked above explains this nicely, with photos. However my actual scribe line was much harder to see than the one in the photos, I think somebody remarked that one with a chisel. I had to sand my balancer and look closely to find my mark, same way with my extra balancer. After you find it You will want to put some white paint or something on it to make life easier.

The quickest way I know of to get the timing close enough to run is to clean around the #1 plug with compressed air and pull it. If you turn the engine manually the process will go a lot easier if you pull all the plugs. Wad up a damp (not soaking, just a little damp) paper towel and pack it firmly into the #1 plug hole and turn the engine over with the crank bolt (clockwise for the 4.9). You can also turn the engine by bumping the solenoid with a screwdriver but its easy to go past tdc if you don't have practice at it. With either method you will hear a pop and the towel will blow out of the hole - now you know you are on the compression stroke.

The timing mark you found earlier should be either on the timing scale or close to it. Turn the engine until your mark is lined up with the larger V cutout on the scale. This is 10 degrees btdc, and where you want the engine sitting to install the distributor. If you want to verify this I will put the procedure at the end of my post.

I have found the Haynes manual to be accurate regarding timing and firing order. Yours is what they refer to as the newer version. It is basically the same for both versions as far as rotation and order, they just moved the location of #1 on the cap relative to the hold down screws. You will want to use the newer version or your plug wires probably won't reach.

So, mark the location (or double check your existing mark) of the #1 terminal onto the top of the distributor base where you can see it easily.

It is worth noting that the oil pump driveshaft - the hex shaped rod sticking out of the bottom of the distributor, is held in with a small snap ring. You can pull the shaft out with little effort, make sure the shaft is all the way in and seated firmly, you may have to reseat the distributor a couple times and you don't want the rod to drop out. If the shaft or clip are worn, a new shaft is less than $10.

Put the distributor in with the module pointing roughly the same direction it was when you took it out, or refer to the cap hold down screw locations in the manual to get the base in the right position. The rotor will turn a bit as it goes down, watch which direction it turns and adjust for it until the center of the rotor points directly at your mark for #1 on the base, and the base itself is in roughly the correct position.

Check where the base of the dist meets the block, it should be all the way down and contacting the block, if it is about 1/8" or so from touching the block the oil pump driveshaft is not in the oil pump. If this is the case, don't try to force it, just pull the dist again and get a straight screwdriver large enough to reach down and turn the oil pump a little bit. It might take a couple tries or it might drop right in. There is another way to get the pump to line up without manually turning the shaft with a screwdriver, but that's a secret!

Replace the bolt and hold down leaving it loose enough you can turn the dist, but not loose enough it can turn itself. (don't turn the dist by the module, might break it.) Reinstall the plugs, cap, and wire it as shown in the Haynes manual and fire it up.

Timing should be close enough to run, but prob not close enough to run well. Let the engine come up to operating temp and set the timing with a light. 10 degrees btdc is the factory spec, but my 4.9 runs better at 12 degrees and from what I hear most of them do if the plugs and wires and coil are in good shape.




To Verify TDC:

Find an assistant to watch, or if you can turn the engine from above with a breaker bar or ratchet (which you probably can't on the 4.9) you don't need an assistant. Pull all the plugs if you didn't already, then feel with a plastic drinking straw into the #1 spark plug hole. You should be able to feel the top of the piston easily with the straw. If you can't feel the piston, turn the engine (clockwise) until you can.

Leave the straw sticking out of the spark plug hole and turn the engine (clockwise) slowly, the straw should raise up a little, then sit still for a little bit, then start going down. When it starts going down make note of the balancer position.

Now turn the engine backwards (counterclockwise) the straw should rise a little, pause, and start going down again, stop here. Directly between this point and the position you noted earlier (straw moved down clockwise) is tdc. Top dead Center (tdc) can either be on the compression stroke or the exhaust stroke, if you did the paper towel trick from above you should be on tdc compression stroke.

Check for your timing mark, it should be at 0 degrees, or just a little above the larger 10 btdc V shaped cutout. Turn the engine back to the larger cutout and you are ready to install the distributor.

 

Excellant info, Thank you, thank you. This has been a super PITA, just for two little screws! Consdiering at one point while pulling the distributor I managed to drop the hold down wedge, down the distributor hole! Flex magnet was NOT successful in retrival. So I ended up pulling the pan and fished it out. New Gasket installed. Than to top it off, my spout connector disappeared. Not sure were it went, but my neighbors curous 8 year hold was "helping" me and asking 1,000 questions. Not sure if it got knocked off into mans land or walked away! So had to get one of those from a junkyard.
So I think at this point I'll verify everything from square one. TDC on Compression lined up just above the big notch (10BTDC) Set at 10 as my base timing. See if I can get the distributor to seat. Thanks again I'll keep posting progress.

 

Again thank you for your help! Tweaking the worm gear for the oil pump made all the difference, for getting that "one tooth" to be right on the money. It starts and runs, now all I have to do is fine tune the timing with a light. Thanks!

 

Got a timing light on it and set it at 12BTDC. Spout conector reinstalled. Idles smooth. But no get up and go! Plus it only starts when it wants toooo. LOL I think I have other issues. Possible worn or weak electronic pick-up inside the distributor and or a bad throttle position sensor. Neither of these have ever been changed and the truck has 140,000 miles. Any imput to this is greatly welcome.

 

Glad to hear it is running!

Sorry I forgot to mention the spout connector, glad you already knew about that part.


Is the engine light on?

Has the truck had a tune up recently?

How about the fuel filter? If its not new, I'd pull it and check it if you are short of cash or just replace since you already have it out.

Those are the only things I would consider replacing until you can figure out what is bad and test it. Replacing parts that don't need it gets expensive fast and with the quality of parts these days can even make the situation worse. Sadly your 20 some odd year old part may be better than a new replacement.

If a tune up and filter don't fix the problem, or if they are good, (or if you have an engine light on) then I'd check the codes. There are 3 classifications of codes, KOEO - Key On Engine Off, CM - Continuous Memory, and KOER - Key On Engine Running.

This site has instructions for pulling the KOEO and CM codes:
http://oldfuelinjection.com/?p=13

Here is a video I found, it shows KOER test, and may be easier to understand since it is visual:

The KOER test may show if there is a problem with your tps, but it can be picky about the WOT (Wide Open Throttle) test and say there is a problem when there is not.

There is also a timing control portion to the KOER test, but you would have to have somebody looking at the timing with a light - shortly after the WOT test if I remember correctly. I'm a little fuzzy on that because my scanner tells me when to check the timing.

Another way would be to use the test light method (explained in article on site I linked first) instead of the interior engine light. Then you could watch the flashes from under the hood and be able to check the timing control by yourself.

Oh, you may notice a difference in how they ground the test lead. The article has you ground it to the battery or the body and the video uses the Signal Return. The signal return is basically a ground circuit for the computer (all the sensors use this ground) so either way will work.

You could get ahold of a code reader/scanner, but the manual way is free.

Parts stores around here don't seem to have OBD1 readers for some reason, but might in your area.

Another thing that might be good to check is the fuel pressure, around 55 to 60 lbs at idle I believe, should drop off a bit and then come back up when you raise the rpm's. If you shut the truck off and just cycle the key to the on position a couple times without starting the truck, it should hold pressure for a fair amount of time.

Also a good time to check fuel pressure regulator while you have the guage on the system. Pressure should go up 10 lbs or so if you unplug the vacuum line to the regulator and block it off with your finger, should go back down when you put the line back on.

Time for me to go to work, good luck.

 

Mystery solved! Did a pressure reading of the fuel pump. Reads 45PSI, good enough to let it run but not good enough to let it start on it's own. (starter Fluid assist!) R2 the fuel pump, now it works as advertised. I'll go out later and reset the timing, now that I have good fuel presure. Thanks for your assistance.

 

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