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Discussion Starter #1
1989 5.0 AOD
Did lower + upper intake gaskets in this truck + added many parts during the repair such as new Distributor/TFI, TPS, FPR, and explorer injectors.

Got it running but at high Rpms it falls flat on its face almost stalling no matter what gear it's in. I'm not sure if the distributor was set in 180 degrees off or if the harmonic balancer halves have spun. Or if a new part is at fault such as injectors or FPR.

You tell me. Does pic look like it's 180 degrees off? Timing pointer is at 10 degrees BTC and rotor is pointing at core support.
 

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Are you at top dead center of the compression stroke on #1 cylinder when you are checking it?
 

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Discussion Starter #3
I hadn't originally set the tdc with the new distributor; previous owner did and said HB may of slipped rotation and needed replaced.
So just now I pulled the distributor and I'm getting the puff of air under my thumb (tdc) 180 degrees out/off of the 10 BTC.

Is it safe to conclude the harmonic balancer has indeed slipped 180 degrees? Pic from top TDC (notice my light scratch mark on side of HB) and pic from bottom at TDC cylinder #1.
 

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'96 XL EEC-V 347 E40D 1356 411 6" lift 35x12.50x15
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Maybe paint an alignment mark on both parts of the HB and fire it up,
if it moves during your test run,,,, you know the rest....
 

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Discussion Starter #5
Tried to restab the distributor at tdc but won't start due to being so off (same problem PO expressed spun no marks to go off of). Going to conclude it spun and replace it.
 

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Man of endless projects
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it would not run with timing 180* off. its hard to start with timing 40* off for that matter. and theres 720* of possibilities since theres 2 revolutions of crank per combustion

unless you are thinknig the fuel injector timing is off. the dizzy caps sometimes have a 1 on the cap to designate which post should be plug 1. the rotor should point to that post when you stab it with cylidner 1 in at TDC compression stroke. this will make the fuel injectors fire at the correct time. how much this will affect performance is iffy. in a batch fire fuel injections 6 of 8 injectors are fired out of time anyways. however on the Explorer 5.0, the service manuals specificly state that if the camshaft syncronizer (replaces distriburtor on coilpack engine) is installed wrong, the incorrect injector timing can damage engine.



did you pull the SPOUT when checking timing? was the SPOUT put back in? SPOUT needs to be removed when checking timing otherwise it will be be retarded and loose power. same if the SPOUT is left out. when you are done setting timing and put SPOUT back in, watch the timnig and rev the engine to make sure timing advance is working

the balancer may have spun. pull plug one and put a soft rod in it and slowly approch TDC on the balancer to verify if it is accurate. use a soft rod so it doesnt bind and damage anything like spark plug threads

does the truck run smooth otherwise? maybe wrong firing order? any misfires? any codes? idle smooth? vacuum lines correct and undamaged? vacuum leak? sensors plugged in? clogged cat? TPS issue?

might need to pull plugs and see if any cylinders specifically have any issues
 

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1986 Bronco, 351w, Edelbrock aluminum top end, Holley 600, 4" BDS lift, 35" Maxxis Razr's, stuff..
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1989 5.0 AOD
Did lower + upper intake gaskets in this truck + added many parts during the repair such as new Distributor/TFI, TPS, FPR, and explorer injectors.

Got it running but at high Rpms it falls flat on its face almost stalling no matter what gear it's in. I'm not sure if the distributor was set in 180 degrees off or if the harmonic balancer halves have spun. Or if a new part is at fault such as injectors or FPR.

You tell me. Does pic look like it's 180 degrees off? Timing pointer is at 10 degrees BTC and rotor is pointing at core support.
In the dizzy photo this is taken from the front, correct. So it’s pointed at about 5 o’clock?

So you found TDC, and went back to 10 BDTC on the crank,

then removed and reinstalled the dizzy with the rotor pointing at 1 (typically about 2 o’clock),

and you’re sure all the plug wires are assigned correctly?

Did you check TDC with a stick per Kingfish? Get on the puff stroke then fine tune with the stick.


Sent from my iPhone using Tapatalk Pro
 

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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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Im voting for spun balancer. That rubber looks pretty hard, maybe broke, cant quite tell on my phone.

Dont buy a dorman one... Mine lasted 1200 miles, yes 1200.
 
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Put it to tdc and set the timing with s vacuum gauge. It'll get you running while you order a balancer.
 

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The best way to find if it's at TDC is to pull the number 1 spark plug and VISUALLY confirm that the piston is all the way up. You can also do this by putting a long screwdriver down into the hole and watch it rise.
When it's at the very top, the timing mark should be pointed at (or very close to) zero. If it's way off, the HB is bad.

Then, once the HB is good, to set the distributor:

Make sure the engine is at TDC on the compression stroke. You can confirm this by rotating the engine clockwise and wait until you feel air coming out of the #1 cylinder. Then continue to rotate the engine and put the timing mark at your desired timing (ie. 10°).

Point the rotor toward the #1 post and then stab the distributor and make sure it's fully seated. Once it is, rotate the distributor housing until the closest arm on the stator (the star underneath the rotor) is pointed at the magnetic pickup.

Tighten it all down and put it together. When you fire it up, your timing should be dead on.
If it sputters, backfires, and pops, you got it stabbed on the exhaust stroke and it's 180° out.
 
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