Ford 302 F150 timing chain/distributor help please!!

story: Ford pickup suddenly stopped running, though several months before I had replaced a leaking timing chain cover, new water pump etc. - I noticed the chain was very loose, but I was ignorant and did not replace. Anyway, after getting the pickup home I could not get any fire to the plugs, and thought about the chain. Did the chain jump? Slowly but surely I replaced just about everything - new distributor, plugs, wires, cap, rotor, coil, module, and finally the chain and sprokets. When put back together it starts but dies when put in gear and barely idles, but occasionally will run perfectly. When the harmonic bearing mark shows TDC for number 1 piston, the rotor points to number 4 piston on the dist. cap. When I replaced the timing chain and gears I aligned them with marks pointing to each other, though the rotor again was not pointing to number 1 on the cap. Help!!!

thanks for any input Shawn

Reply to
Shawn
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Shawn opined in news: snipped-for-privacy@mb-m06.aol.com:

That was confusing as he!! How about year of truck/engine and please go through the pertinent info not in detail sequence, but as it ended up!

iOW as it stands NOW!

here's how i understand it:

-timing chain replaced, marks lined up on sprockets, straight line from cam center, across marks to crank center

-rotor points to cyl 4 at tdc

-engine USUALLY runs like crap but sometimes perfectly

here's what I think is the firing order:

1-5-4-2-6-3-7-8

So i cant see how that can happen... are you SURE you know which is #1? it's the frontmost cyl.

Reply to
Backyard Mechanic

Sounds like you distributor is in wrong.

You need your distributors rotor to point at the #1 plug while the engine is at Top Dead Center TDC of your Compression stroke on the #1 cylinder.

I pull the #1 plug then stick my thumb over the spark plug hole and bump the starter until the compression pops my thumb off, (this indicates that you are starting your compression stroke) At this point I insert a long plastic drinking straw into the cylinder (you could use a long plastic zip/wire tie, I like plastic cause it can't scratch or gouge threads, cylinder walls or piston tops) then I spin the crank by hand (with a socket and ratchet/breaker bar if needed) until my high tech plastic indicator reaches the top and starts back down, I move the crank back and forth to insure I am at absolute Top Dead Center. Works right every time. Now for inserting the distributor, there is not much space between the distributor gear teeth, it is quite easy to miss by one (maybe more) tooth. Be very observant and careful during this part of the process. The gears wrap around the distributor shaft, and it ends up sliding into a different spot then it starts at, you have to allow for that when you start out. If your oil pump drive is leaning to far to one side to easily slip up into the distributor shaft you can stick a glob of grease between the low side of the hole and the oil pump drive shaft to hold it in the center. If it's not right pull it out and do it again.

Good Luck

Reply to
351CJ

If the timing is off since you installed the timing chain, you either did not get it right or you failed to properly torque the damper bolt allowing it to shear the key or, the cam sprocket bolts were not properly tightened allowing them to loosen in which case the cam is not likely turning at all. Those are things you have to determine to your own satisfaction.

First step in timing the engine is the cam. Do not rotate the engine with the cam chain off unless you have removed all of the rockers to prevent valve damage. Removing all of the spark plugs will ease turning the engine if it still has decent compression. You should have the crank sprocket and cam sprocket marks aligned when you install them. If you are installing a timing set with multi timing, make sure you are using the "0" mark unless you have good reason to chose one of the others. When you drop the distributor in, the rotor should be, as nearly as possible, just before arriving at the #1 post when fully inserted and properly oriented to allow timing adjustment. You may have to rock the engine back and forth a bit to get the oil pump drive to align enough to drop the distributor in. This is easily done before the front of the engine is buttoned up so you can tell exactly what you are doing. Once the distributor is in and located so that timing can be adjusted after the engine is actually fired, the TDC mark on the damper should be aligned with the timing pointer indicating "0". When you install the plug wires, make sure you use the correct firing order. The regular 5.0L/302 uses one firing order while the

5.0L HO and 351W uses another. Some performance cams for the 5.0L will use the same firing order as the HO & 351W.
Reply to
lugnut

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