Sunday, March 18, 2012

Setting The Timing On Your Mustang

Every once in a while you will need to adjust the timing of your car.  You may do it for various reasons, one of which is to get a little more performance out of your car. 

Recently I had changed the engine in my Mustang, so now I will need to set the timing.  This post will cover how to do that.  I will point out the differences between the 94-95 and the 86-93 Fox body 5.0L engines.
Since I have the luxury of owning both models of 5.0L engines with a 95 and an 86 Mustang GT, I will show you how to set the timing in each model of the car.

The biggest difference in these two models of cars is the location of the spout connector.  on the 86-93 cars, the spout connector can be found next to the distributor.

As you can see the spout connector on my 86 is black.  It can be found right next to the distributor and needs to be removed prior to checking or setting your timing.
Here is an example of the spout connector on my 95.  It is gray and is located on the passenger side fender area by the Mass Air Flow box (where your air filter goes).  Just like with the 86, this spout connector needs to come out prior to setting or checking your timing.










Ok, by now you are probably wondering why we have to remove this spout connector.  The answer to this is the same in both scenarios.  If you have the spout connector in, the computer will actually automatically adjust your timing for you based on the situation that your car is running.  In certain circumstances it will retard your timing and in others it will advance your timing.

Your next step is to make sure that your harmonic balancer has the appropriate markings highlighted so you can see the timing value you want to set.  From this point on, I am only going to be referencing the 95 as the information is the same.  When I put my engine in my car, I installed a brand new harmonic balancer.  I took a silver marker and highlighted the lines on the harmonic balancer from 0 to 20 degrees advanced.

If you noticed, each line represents 2 degrees.  I placed an extra long line on the 10 because that is what the Mustang is timed at from factory.  This is the setting I should be aiming for with my stock car.  There are times when you would want to advance your timing.  This is why I have highlighted the bars after it.  It helps identify how advanced the timing is on the car.


There are 2 special tools you will need when performing this task.  One is a distributor wrench while the second is a timing gun.  If you look at the picture on the left, this is what a distributor wrench looks like.  You should note the difference in the shapes of the ends.  You could use this wrench as is and get the job done, but I would recommend using this with a ratchet.

The thing to note about the distributor wrench is that one end is a 1/2 inch while the other end is a 9/16 inch.
Depending on the make and model of the car you are working on will determine which end you need to use.

If you look to the left you will see we will be using the 1/2 inch end for our application along with a ratchet.  This usually makes things much easier to get tight.
The second special tool you need is a timing gun.  If you look to the left, I have one pictured here.  There are all sorts of brands, I just happen to have a craftsman version as those are the tools I typically use.

There are 3 ends that need to be hooked up with the timing gun.  The first two are the clips that get attached to the battery.  This powers our timing gun.  The third is the piece that hooks up to the first spark plug to signal that an electrical charge is going to the first cylinder.  Because of this you will need to clip this around the plug wire for cylinder #1.  don't worry, it doesn't pinch the wire or anything.

If you look at the base of the distributor you will see a bolt and fastener that need to be loosened.  Without this being loose, you won't be able to slightly turn the distributor to set the timing to the appropriate spot.  You will want to take your distributor wrench and loosen the bolt.

Make sure you remove the spout connector from the car and put it in a safe location.  You don't want to lose this piece as it could be very expensive and hard to locate a replacement.

To set your timing you will be aiming your gun pointed at the harmonic balancer from over he alternator.  Once you get in there, you will see what I am talking about.  If you are not in the right location, you won't be able to see the markings you put on your harmonic balancer.

I am going to assume your timing gun is now hooked up.  It is time to start your car.  You cannot time your car without it running.  It is a fact of life.  You will just have to deal with this.

Once your car is running and everything is hooked up you will ned to aim your gun to the appropriate location and pull the trigger.  What you will see is a rapid series of flashing lights that illuminate when the spark hits the first cylinder.  It works kind of like a disco light does, everything seems to be frozen for a fraction of a second at a time and his allows you to see the timing value you are at.

Since your distributor is loose, if you do not like your timing value you can simply turn the distributor and either advance or retard the timing.  Once you get it to the value you want it to be at shut your engine off.

At this point you will tighten the distributor bolt that you loosened in the earlier.  Don't unhook the timing light just yet because we want to verify that the distributor didn't move while we were tightening it.  Sometimes it does and it is just a fraction off and you have to loosen and set it again.

If your timing checks out after tightening our distributor down, it is time to unhook the timing light and put the spout connector back in.

This is a pretty simple process that should take maybe 10-20 minutes to accomplish.    

7 comments:

  1. sorry to hear you are selling your mustang. i have been using this blog as i am attempting this swap in my 87 gt and it has been incredibly helpful.

    will you still be keeping this blog active? I grealy apreciate the insight you offer and your quick responses to my various questions.

    i am gettng ready to remove the harmonic balancer on the explorer to remove the cam so i was reading over your section on that and the section on setting the timing.

    Did you go over removing the distributor from your mustang and swapping it into the explorer? i did not find that info and was hoping i just over looked it. I have never removed a distributor and harmonic balancer before or set the timing on a car.


    thanks for all you help!!!!!!!

    ReplyDelete
    Replies
    1. I must have forgotten that part in this article. The bolt I refer to in it is the only bolt that holds the distributor in. You will need to take the cap and wires off to get them out of the way and unplug the ignition control module. Once you remove that bolt and the clip that holds the distributor down (they come out together) you should be able to wiggle the distributor and pull up gently on it and it will pop right out.

      Putting the distributor back in will be a bit tricky. For this you need to make sure your #1 cyl is at top dead center on the compression stroke. Once you verify this, you line up the rotor on the distributor at the location you have your #1 plug wire. To help you out, it is usually pointing back at the engine. Keep in mind that when you put the distributor down the hole, the rotor will turn slightly so you will need to keep that in consideration when trying to line up your distributor. It is pretty common to be a single tooth off. If this happens, your car will either start, or try to start but will most likely back fire if it starts.

      One thing that happened to me was that I wasn't paying attention on if I was on the compression or exhaust stroke and that resulted in being a 1/2 turn off. If this happens, the car won't start. This is your first clue. At that point bring your #1 cyl back to top dead center and turn the rotor a half turn. and you will be lined up.

      One last tip and I think everything should be covered. At this point I am assuming that you have already primed your oil pump. You can reference my post on this to find out why. Sometimes when you do this, the oil pump shaft is not lined up with the distribor receptical. It's not hard to make this line up, You just need to turn the rotor a bit when you are putting the distributor down the hole. This will turn the oil pump shaft and allow you to line up with your gears.

      There is no exact science to this. That is why they make the timing light and why you have the ability to turn the distributor to advance or retard the timing.

      Good Luck and let me know if you need anything else.

      Delete
    2. I forgot to address the blog question... Yes this blog is going to stay active. I still have the 86 mustang and I am working on the interior of it now. Look for some posting about that soon.

      Delete
    3. For your harmonic balancer, there is a tool you can get from the loan a tool at your local parts store (like Autozone) and it will pull the balancer right off. It only slides on one way so installation is pretty easy.

      Delete
  2. Thanks for the descriptive reply. I got the tool for the balancer but I cant break the nut ont the pulley with my engine on the stand. How did you get that nut loose to remove the pulley?

    Did u sell the 95 yet?

    Thanks for keeping this site active. It has been massive help!

    ReplyDelete
    Replies
    1. Those bolts can be pretty tight. I used a breaker bar to get it broke loose. You will need to prevent the engine from turning over to get this to work. I had my engine on a stand with the old flywheel still in tact and used a prybar to wedge and stop the engine from turning over. If the flywheel is already off, you will be able to put 2 of the flywheel bolts back on and use a prybar leveraging on those 2 bolts to keep it from turning over. At least enough until it is broken loose. You will need to do the same when it comes time to torque it back down.

      The 95 is not sold yet. Probably going to have to drop the price some. It sucks because I have more money stuck into it than I will be getting for it. But can't have 4 cars for 2 people. Especially when you only have 3 stalls in your garage.

      Good luck!

      Delete
    2. This was really clear and very helpful. I had no idea where to look for the sprout connector. Thanks a lot.

      Delete