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1985? 5.0 project car

3K views 31 replies 4 participants last post by  myblue67 
#1 ·
So a friend and I acquired what we were told is an '85 5.0. It's rusty, hasn't driven in years, and gutted inside since the owner put a roll cage, E brake, and shifter for racing. We're going to try to at least get it running since the internals seem to be in good shape. I pulled the carb off and I am not sure what model it is to get a rebuild kit. It's a motorcraft 2 bbl. I thought it was a 2150 but believed those came on earlier models? It's also entirely possible that the car isn't actually an '85 so I will check on that too. There are no other markings that I see and there was no identification tag. What carbs came stock on this year? I will send a picture when I get it out of the chem dip.


Also, where should we start? It was left with the fuel lines and battery unplugged. The carb had some nice spiders in it, but the chem dip should fix that issue. Obviously we will need a new battery but where does one start when given a car with little back story?


Thanks a lot

SG
 
#2 ·
I would check the oil first and get it cranking even without the carb
to see if you have a free turning engine and listen for compression. I would
rebuild the carb or replace it , clean out the gas lines and get rid of any old
gas that might be in the tank Put fresh gas in and try to fire it up. Once you
get to run you can check everything else. Some info I found said your carb
is a 2100 but I'm not sure
 
#3 ·
Thanks a lot for your help! It looks like some of the wiring has been ruined by rats who made their home on top the engine.. is there a way to bypass the ignition switch and get spark to the engine? Also how in depth was the electrical on these cars? I'm way more familiar with the 64-68 mustangs. Do they have an ecu? It definitely runs on points rather than electronic ignition. And from looking up the carb options it seems as though an 85 would have come with a 4 bbl so I'm leaning towards it being an earlier model. Does this sound right? I'll obviously check the VIN to confirm

Thanks
 
#5 ·
Thanks. Are you talking about the starter solenoid on the left fender? Is the starter located on the left side under the exhaust headers as in earlier models? Or somewhere else?
 
#8 ·
Yes that is your starter soleniod. I am more familiar with the 87 and up
models. In the 87 the soleniod is located on the drivers side fender. And
yes the starter is located on the passenger side below the exhaust. In some
ways the 82 is a completely different animal from the 87.
 
#6 ·
And what's the box behind the wiper fluid tank? Looks like an ECU type device. Idk how technological this model was. I'm used to older models. And I foundout it's an '82.
 

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#9 ·
Thanks. Yah I'm more familiar with the 67..so quite different haha. I was able to hook the battery to a charger and get lights to show up on the dash when I turned the key. Obviously the battery is completely dead. But should it not be able to crank the engine if it's hooked up to a charger or some outside device? The engine has oil that's not too dirty and the radiator is completely filled with coolant so I'm hopeful that the engine is in running condition. Is there any way to check that the fuel pump is working?
 
#10 ·
In some cases you can crank it when coonected to a charger but probably
not with a completely dead battery especially when it won't hold a charge.
If I am not mistaken you have a mechanical fuel pump which needs the engine
cranking to produce fuel pressure. You can check that after you clean out the lines
empty the tank and refill with fresh gas.
 
#11 ·
#13 ·
The 82 5.0 Mustang came equipped with a 2 barrel Motorcraft 2150 carb & Ford stepped up to a 4 barrel Holley 4180 carb on the 83-85 models with a 5 speed.They used CFI on the automatic models.
The idle air mixture cannot be adjusted because of a tamper proof primary metering block.The 4180's secondary metering blocks can be replaced with the blocks from a 4150 carb,after minor modifications,which will improve WOT performance.

The box you were asking about is referred to as a Duraspark ignition module.

You should be able to check the fuel pump simply by turning the key to the start position to crank the engine for 5 seconds at a time.If you dont have a friend around to crank the starter while you watch the fuel line,you can just wedge a pipe/sledge hammer handle between the seat & clutch pedal to keep it floored,turn the key on and hold a screwdriver across both solenoid posts to jump the starter.Aim the fuel line into a gas can so you can get an idea of how much is coming out.Since the fuel lines are probably completely empty from sitting,it might require a few key to start cycles to get the fuel line primed.
 
#16 ·
Thanks for the reply. I have confirmed that it's an '82. It has an automatic trans but I haven't confirmed that it is stock. It has some racing 3 speed shifter on it that doesn't quite work, that I need to figure out how to fix. So I was assuming for the fuel pump that once I was able to finally crank the engine I would know if it were working if fuel started shooting out. I accidentally did that on my '67. Was a real fun clean up. :D
 

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#23 ·
So we hooked the battery to a quick starter. Used the method of connecting the solenoid contscts. Kept getting a weird constant humming from the coil. The starter didn't crank. I pulled both. The starter appears to be in working condition. Is there a way to bench test it? I'm going to replace the coil. And battery.
 
#24 ·
Are you sure the humming noise is coming from the coil?? It could be coming from the starter solenoid,if the contacts got welded together due to low battery voltage.Lightly smacking the solenoid with a hammer will unstick the contacts.You also need to make sure the metal plate on the back of the solenoid and the fender apron surface has clean metal to metal contact because the solenoid is case grounded.If this area is not clean or the mounting screws arent tight,that will keep the solenoid from grounding.
The following link details how to test the coil.
Part 1 -Ignition Coil Test -No Spark No Start Tests (Ford 4.9L, 5.0L, 5.8L)

You also have to make sure (by probing the battery posts with multimeter leads while youve got the key in the start position) the battery has at least 9.6+ volts,either by itself or with the additional help of the jump starter.Less than 9.6 volts=the battery wont physically be able to crank the starter.
The primary and secondary grounds must also be tight & corrosion free.
Primary= neg battery post to engine block.
Secondary= cylinder head (rear) to firewall.

(Source Stangnet)
No Crank checklist for 5.0 Mustangs

No crank, slow crank and stuck starter solenoid problems have the same root causes – low battery voltage and poor connections. For that reason, they are grouped together.
Use the same initial group of tests to find the root cause of both no crank and stuck solenoid problems.

Since some of the tests will bypass the safety interlocks, make sure that the car is in neutral and the parking brake is set. Becoming a pancake isn’t part of the repair process…

1.) Will the car start if it is jumped? Then clean battery terminals and check battery for low charge and dead cells. A good battery will measure 12-13 volts at full charge with the ignition switch in the Run position but without the engine running.
A voltmeter placed across the battery terminals should show a minimum of 9.5-10 volts when the ignition switch is turned to the Start position and the starter engages or tries to engage. Less than this will result in a clicking solenoid, or slow cranking (if it cranks at all) or a starter solenoid that sticks and welds the contacts together.

Most auto parts stores will check your battery for free. It does not have to be installed in the car to have it checked; you can carry it with you to the auto parts store.

The battery posts and inside of the battery post terminals should be scraped clean with a knife or battery post cleaner tool. This little trick will fix a surprising number of no start problems.

The clamp on with 2 bolts battery terminal ends are a known problem causer. Any place you see green on a copper wire is corrosion. Corrosion gets in the clamped joint and works its way up the wire under the insulation. Corroded connections do not conduct electricity well. Avoid them like the plague...

If the starter solenoid welds the contacts, then the starter will attempt to run anytime there is power in the battery. The cables and solenoid will get very hot, and may even start smoking. The temporary fix for a welded starter solenoid is to disconnect the battery and smack the back of the solenoid housing a sharp blow with a hammer. This may cause the contacts to unstick and work normally for a while.

A voltmeter is handy if you are familiar with how to use it to find bad connections. Measure the voltage drop across a connection while trying to start the car: more than .5 volts across a connection indicates a problem. The voltage drop tests need to be done while cranking the engine. It's the current flowing through a connection or wire that causes the voltage drop.


2.) Check the battery to engine block ground down near the oil filter, and the ground behind the engine to the firewall. All grounds should be clean and shiny. Use some sandpaper to clean them up.

3.) Jump the big terminals on the starter solenoid next to the battery with a screwdriver - watch out for the sparks! If the engine cranks, the starter and power wiring is good. The starter relay is also known as a starter solenoid.


4.) Then pull the small push on connector (small red/blue wire) off the starter solenoid (Looks like it is stuck on a screw). Then jump between the screw and the terminal that is connected to the battery. If it cranks, the relay is good and your problem is in the rest of the circuit.

5.) Remember to check the ignition switch, neutral safety switch on auto and the clutch safety switch on manual transmission cars. If they are good, then you have wiring problems.


6.) Pull the starter and take it to AutoZone or Pep Boys and have them test it. Starter fails test, then replace it. If you got this far, the starter is probably bad.

Starter solenoid wiring for 86-91 Mustang

Starter solenoid wiring 92-93 Mustang or earlier Mustang with upgraded high torque mini starter.

Electrical checks for the switches and starter solenoid

Remove the small red/blue wire from the starter solenoid. Use a screwdriver to bridge the connection from the battery positive connection on the starter solenoid to the small screw where the red/blue wire was connected. The starter should crank the engine. If it does not, the starter solenoid is defective or the battery lacks sufficient charge to crank the engine.

If the starter does crank the engine, the problem is in the clutch safety circuit (5 speed) or Neutral Sense Switch or ignition switch.


See the Typical start circuit diagram above for wiring information for troubleshooting.

You will need a voltmeter or test lamp for the rest of the checks. Connect one lead of the voltmeter or test lamp to ground. The other lead will connect to the item under test.
Look for 12 volts on the white/pink wire when the ignition switch is turned to the Start position. Check the ignition switch first.
No 12 volts, replace the ignition switch.

The next step will require you to push the clutch pedal to the floor (5 speed) or put the transmission in neutral while the ignition switch is turned to the Start position.
Good 12 volts, check the clutch safety switch (5 speed) or Neutral Sense Switch for good 12 volts on both sides of the switches. No 12 volts on both sides of the switch and the switches are defective or out of adjustment. Check the wiring for bad connections while you are at it.
 
#27 ·
The coil harness wires usually originate from a plug that connects to the Duraspark module I believe.Look at the picture below and trace the coil wires to see if they lead to a harness plug.Its the harness listed for a 79-85 model.
Did you download the pdf's then compare your harness wire colors with the matching year in the pdf?? 79-86??

In your original post,you stated you didnt know what year the car was.Do you mean the cars year or were you referring to the year of the engine/components?? The vehicle safety certification label on the driver door will tell alot about the car.The vin will too.The 10th digit lists the year.H=87 J=88 K=89.You can go backwards for earlier models.You would have to look on the block in the starter area to get the blocks year model,which is in casting # form.

Did you see sparks coming from the coil at the coil post/distributer wire area?? If yes,that usually means your wire is leaking voltage (arcing) The plug wire is likely bad.If its arcing,the other spark wires might be too.If its not the wire arcing,the coil might have a crack in it,arcing voltage from that crack or are you referring to the area where the coil harness plugs in??
 

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#28 ·
I was able to confirm that the car is an '82. The spark was coming from the distributor wire area to the coil post. I tried to find that wiring harness in that picture at NPD and there's was not as complete.
 
#29 ·
Here you go.I got the picture from LMR (Late Model Resto.com) The link is below.Its high though $139.99.They also sell just the coil harness pigtail with two wires also for $9.99........
It says the harness is a stand alone assembly though and not the original harness.It says its used for efi to carb conversions,so you mighy need something simpler.It says it'll work with splicing,but whays the point of spending that kind of cash if youve gotta splice,right?? I'll see what the harness looks like on the diagram and hit you back tomorrow.

https://lmr.com/item/LRS-14289A/1979-85-Mustang-50L-Duraspark-Harness

https://lmr.com/item/HDW-12029A/Mustang-Coil-Connector-w-Pigtail-Harness-79-85

I'll download those pdf's tomorrow and look through the 82 harness,now that we know what year were dealing with for sure.
 
#30 ·
Oh thanks a lot. I just got a new battery and I'm going to install it so I can see what the next step is.
 
#31 ·
Good news/bad news. Put the battery in and turned the key and nothing happened. But then when we did the solenoid jump, it started cranking. What exactly is the solenoid jump bypassing? And where should I start next. It's obviously an electrical issue at this point.

Oh and where is the neutral safety switch so I can check that like you said.
 
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