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1991 Ford Bronco 5.8L XLT
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Discussion Starter #1
I just pulled the engine to replace the oil pan gasket, timing chain cover gasket, water pump gasket, oil pressure sensor, manifold gasket, upper manifold gasket, valve covers gaskets, etc. Basically took the whole thing apart and put back together with new gaskets. Something is misfiring though and I'm not sure what. It's my first time "rebuilding" an engine and would appreciate any help/direction of what to try.

Here's a link to the video: New video by Will Mitchell
 

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1991 Ford Bronco 5.8L XLT
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Discussion Starter #3
I really appreciate the help!

I am not sure. The yellow mark I made when I removed the distributor is back in the exact same place, but I may have rotated the crankshaft. Would you remove the distributor and rotate the crankshaft 180 degrees and put it back in?
 

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Man of endless projects
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pull spark plug 1. rotate crank slowly with finger over hole till you feel pressure. rotate till at 10*. that will ensure your at compression stroke.

pull distributor. stab it in so the rotor is pointing to the post for plug 1 (come caps have 1 to identify). make sure order of plug wires are correct. this ensures fuel injectors fire in sync with spark. you will need a timing light to get timnig perfect but this will get it running if timing is the issue

 

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85 Bronco, 309ci I6 w/4bbl, np435, 4" lift, 37" Irok NDs, 4.56 w/ Detroit Locker and tru trac
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Okay so you need to pull the valve cover, and get the #1 piston to top dead center (TDC). Watch the rocker arms and rotate the crankshaft. Remove the #1 spark plug and jamb your pinky finger in there. You should be able to feel when tye piston stops moving up and starts to move down. TDC will be there twice per cycle. One on the compression stroke and once on the intake stroke. You want to measure TDC when the piston is moving up and the exhaust valve is closing. When it gets to the top, that is TDC. There will be a few degrees of crank rotation, where exact TDC cant be measured accurately. But thats why we have adjustable timing!

Now pick up the distributor, and mark the #1 spot on the body of the distributor. Point the rotor tip at that mark, and move it about 1/8" to one side because the gear on the bottom is helical. It'll move the rotor over to your mark as you insert it into the block. If the rotor points farther away, you went the 1/8" the wrong way. Pull the distributor and try it the other way. That should get you where you need to be to get it started and ready for setting the base timing. Any time you adjust the distributor in a EFI ford, the SPOUT connector must be unplugged.
 

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1991 Ford Bronco 5.8L XLT
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Discussion Starter #6
Big thanks to @BigBlue 94 and @Kingfish999 for the help. I got it back running this morning which was awesome. I'm going to summarize my steps for those who are dumb like me and don't know all this fancy lingo.

Proper Installation of the Distributor on a 1991 Ford Bronco 5.8L
1. You need to know what all the numbers mean. The firing order and number of the pistons are on this page: Ford Bronco Ignition. Essentially passenger side goes 1-4 front to back and then drivers side 5-8.
2. Now pull out spark plug #1. This is passenger side front.
3. Turn crank shaft until you feel pressure. As @BigBlue 94 notes, one time around is intake and one is compression so you can go around 10* twice. VERY IMPORTANT!
4. Once you feel the compression, rotate until your 10* mark on the balancer lines up with the timing gauge. This image shows it pretty well. http://img.photobucket.com/albums/v691/Doomsmith/TimingMarks6.jpg~original
5. Now that you have it aligned. Pull out the distributor.
6. Remove the distributor cap! The cap is what @Kingfish999 showed above. Underneath the cap it looks like this: https://www.supermotors.net/getfile/924199/original/pip-(40).jpg. Yes, like a single arm spinning around.
7. Now place the distributor back in the engine and mark where the distributor is pointing on the outside of the cap. (There is a white mark in the picture in #6).
8. Now place the distributor cap back on noting where the mark is and which wire it's going to hit first. Important to note that it spins counterclockwise.
9. Now place spark plug wire going to spark plug 1 at that first location. Then so on and so forth in the order linked in Step 1. Or here: 1,3,7,2,6,5,4,8.
10. Reinstall spark plug #1 and spark plug wire number 1.

Now as @Kingfish999 notes you should adjust this with a timing light once you get it running again, but I haven't done that yet. Seems like a lot of good Youtube videos on it though. Again, big thanks to @Kingfish999, @BigBlue 94, and @MS88Bronc for your help!
 

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Addicted to Junk
85 Bronco, 309ci I6 w/4bbl, np435, 4" lift, 37" Irok NDs, 4.56 w/ Detroit Locker and tru trac
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Other than you getting it running, the best part is you learned how to do it! That's why we're here!
 

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Man of endless projects
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the only issue is that your fuel injectors arent perfectly in sync with ignition if you do not install the distributor with the rotor at the correct post. its not really a big deal, especially for batch fired fuel injection and most people dont bother but its good practice to do. there is a 'hall sensor' in the distributor which can determine when its firing cylinder 1 so it knows when to fire the fuel injectors.

the reason its not important is because older trucks with batch fire fire 4 injectors at same time and the other 4 on the next revolution. so 6 of the injectors will always be out of time regardless how you do it. but it can make it abit more efficient if done correctly so the fuel sprayed in intake doesnt have to wait almost 2 revolutions to be used

the later trucks with sequential fuel injection actually fire the injectors in a proper order and can benefit better from it being installed correctly. especially the trucks with misfire detection
 
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