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5.0L (1979-1995) MustangTechnical discussions on 5.0 Liter Mustangs within. This does not include the 5.0 from the 2011 Mustang GT. That information is in the 2005-1011 section.
OK still no start...
Timing looks good I have it at about 12 degrees
New wires, new cap and rotor, and replaced the 2.3 with a 5.0 bap sensor.
What should I check, I have fuel, I'm gonna pull a plug and check spark here in a bit.
TFI module??? (I've seen a few threads with issues with this)
Update: Switched out the distributor base/tfi module and pulled #5 plug and checked for spark. Have spark (looks strong, blue) Set timing to 13 BTDC and tried cranking again...got a massive backfire (knocked insulation from the ceiling and had the neighbors running out of their house to see what happened)(sprayed a tiny bit of starting fluid in about 5min before the backfire) So I'm gonna call it quits for a bit but it's never tried to fire off like that before. So I have 2 theories: 1 Bad TFI, 2 the lifters are a used set and felt on the soft side and they're finally pumping up with oil and are actually opening the valves.
Last edited by Aaron Schulte; 10-15-2018 at 06:23 PM.
It sounds like a timing issue,if its backfiring.
How exactly did you go about setting it to 13° without the engine running??
When you dropped the distributor in the block,was the #1 piston at tdc on the compression stroke?? If air wasnt felt coming out of the plug hole right before the 0° mark & timing pointer were aligned (while you were rotating the crank) you're on the exhaust stroke instead.
If it was indeed on the compression stroke like its supposed to be,was the 0° balancer mark and the timing pointer aligned with each other when you dropped the distributor in the block so that the rotor was pointed at the #1 position on the distributor cap,with the distributor fully seated??
(Or)
Did you rotate the crank until you felt air coming out of the #1 plug hole,then stop rotating it once the 13° balancer mark was aligned with the timing pointer, then drop the distributor in the block so that the rotor is pointed at the #1 position on the distributor cap, with the distributor fully seated??
Second method...I'm almost off work but I'll double check and try again here in a bit.
YESSSS!!!!! It's Alive. I was 180 degrees off. Ran it for 20min at around 1900-2300 rpm , no leaks other than a little coolant out of the cap while warming up. No weird noises. I still have to finish up alot of little stuff but it runs!!!! I locked the distributor at 12 degrees initial and put the spout back in.
Last edited by Aaron Schulte; 10-16-2018 at 05:30 PM.
Im glad to hear you got it running finally.However,if you used the second method (with the 13° mark aligned with
the timing pointer when you dropped the distributor in place) that indexed position
of the distributor isn't correct.The engine
will start and run with it in this position,
but it'll be off by quite a few degrees.If you click on the link at the bottom,then scroll down to the DONT(S) sections in black/
red then read all the information thats Timing related,it will explain what occurs when the distributor is indexed incorrectly.
Something else I wanted to mention,related to timing,is score marks.This info is only valid/helpful if the block & distributor youre working with are oem parts (explanation= when the 5.0 engines were assembled at Ford,the engine builders would take a hammer/chisel & cut a score mark in the block & distributor housing to identify the oem 10° base timing setting,so that timing could be set correctly in the future without the use/need of a timing light.The picture below shows those score mark locations. They will help if youve got the oem block & distributor still.All you have to do is get the
#1 piston to tdc on the compression stroke, with the 0° balancer mark aligned with the
timing pointer,drop the distributor in the
block so that the rotor is pointed towards
the #1 cylinder position on the distributor cap then rotate the distributor until its oem
score mark is aligned with the oem block
score mark and timing will be sitting at the oem 10° position.
I think the timing is dialed... I have a stock distributor and matched up the marks like your picture and added 2 degrees so it's like 1/8th in off. I have 16-17 in/hg vacuum at idle 750-800 rpm rock steady with not more than 1/2 in/hg of flex. With an e303, ported e7's, and ported gt40 I think that's a pretty good reading.
Gotcha.I just wanted to give as much info as possible so you could double check everything.On a carbed engine,its easier to get away with the ignition timing being off a few degrees compared to a sefi engine,which requires the timing to be pretty specific in order to prevent the injector sequence issue described in the link.
10-14-2018, 03:02 PM
