Testing my patience

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Jayro

Well-known member
Joined
Mar 30, 2022
Messages
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My Car
73 mustang baby blue with clevo 351
Hey guys,

Looking for some advise. So the new 351 went in. Now I know I’m not great at setting timing so had it towed to a tune shop. The guy seems to be very knowledgeable and has put an effort in. Dyno result was disappointing but apparently the accelerator cable is not allowing full range on the holley. Apparently car is idling and driving ok. So It’s a new accelerator cable and bracket to come.

Onto the next and main issue. Car won’t start without jump starting it. Has a brand new battery and the battery checks fine. Seems the starter solenoid possible issue and there is a black box under the starter solenoid that bolts to the inner guard, any idea what it would be?

Also he is saying to replace the alternator? Could this cause this not start issue as well or? I’m just not sure as the alternator has been fine do not sure why the day we try to get the new motor cranking we decide it’s dead.

Happy to replace anything but not just for the sake of it.

Cheers
Jase
 
The box under the starter solenoid is usually the voltage regulator. Stock color is blue, but some after markets might be black. If it starts with jumper cables it is not likely a solenoid issue as the solenoid still has to work properly to engage the battery + to the starter. The symptoms point to a weak battery terminal connection or a weak battery. Was the battery load tested? Where the jumper cables both connected to the battery terminals? Or was the - (black) connected to an engine ground?
 
You don’t need a new accelerator cable unless it’s frayed. There’s an adapter to get the correct range of movement for the cable. If your mechanic doesn’t know that, then you need another one.
 
When you say you can't start the car without a jump - what does it do when you try to start it? Does it just click, or turn over slow or what? The alternator wouldn't have anything to do with it not starting unless it's not charging the battery. +1 with jpaz on the adapter for the throttle.
 
So when we try to start it with jumping it it just clicks. Battery terminals are great, battery tested fine. When it doesn’t click on the odd occasion where it will start to turn she fires up great.

Great to know about the cable extension. Thank you.
 
How was the battery tested, or checked?
If it was checked with just a voltmeter and without a load on the battery that will tell you nothing about the battery condition. A battery with a bad cell can still show 12 volts, but when a load is placed on it drop to less than 10 volts. Connect a voltmeter to it and turn ln the headlights and heater fan, see what happens to the voltage.

When you jump it where do you connect the negative cable? It's also possible you have a bad ground.
 
How was the battery tested, or checked?
If it was checked with just a voltmeter and without a load on the battery that will tell you nothing about the battery condition. A battery with a bad cell can still show 12 volts, but when a load is placed on it drop to less than 10 volts. Connect a voltmeter to it and turn ln the headlights and heater fan, see what happens to the voltage.

When you jump it where do you connect the negative cable? It's also possible you have a bad ground.
Ok thanks for that mate. I’m picking the car up in an hour to get it home. Then I’ll test it and check those things and will confirm where he is connecting to jump it.

Thanks 🙏
 
You don’t need a new accelerator cable unless it’s frayed. There’s an adapter to get the correct range of movement for the cable. If your mechanic doesn’t know that, then you need another one.
He is saying that when foot down all the way that it’s not got the range to open the carby all the way. So are you saying there is an extension of sorts I can use? Because $600 for a cable and bracket doesn’t excite me 😆
 
You don’t need a new accelerator cable unless it’s frayed. There’s an adapter to get the correct range of movement for the cable. If your mechanic doesn’t know that, then you need another one.
What is this "adapter" you mentioned, and where does one purchase it? I had swapped a four barrel into my two barrel car years ago, I don't believe I used any adapter for the cable linkage. I do remember an extension that Holley sold for the kickdown lever to work properly.
 
No one seems to have mentioned the GROUND cable to the motor. I'm not sure what the 73's had ,but the 71's had a cable that not only attaches to the motor, but also the body at the voltage regulator. The connections must be clean, zero paint! On mine, I have 2 grounds attached, one at the back and one at the front. Maybe overkill, but......
Here is the pic that shows the body ground connection.
 

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For the accelerator cable adjustment I enlarged the holes in my cable bracket (see pic) to allow fore/aft adjustment. I also used this bushing: https://www.amazon.com/Moroso-64920-Carburetor-Linkage-Bushing/dp/B000CONZ7Y along with a ball stud to connect the cable end to the Holley carb. These two steps allowed me to get full travel on the carb with the stock cable.
1659799896903.png
Also, there may be a difference in cable length between the stock 2v and 4v cables for 73. Not sure this would be an issue, though.
 
A throttle cable costs around 45 buck US, where is the 600 coming from?
There are two cables. the 71/72 has a different pedal connection to the 73. Make sure you buy the cable that matches your throttle pedal. A few months ago, I needed a new cable, the old one snapped, and for some reason, I had to shorten the cable at the pedal by nearly 1". I could not get full throttle.......... or even half throttle.
Check the cable on yours for this problem. To fix is not easy. I opened up the eye crimp, cut the cable where necessary, re-crimped the cable then siler soldered the joint, but lead solder will work as well, Make sure it's clean and zero oils or grease, even finger oils.
I have some pics somewhere. If I find them I'll update.
 
Agreed with Stanglover. Check the motor ground. A jump will provide that ground (depending on where you clamp the cables).
 
Hey guys,

Dyno result was disappointing but apparently the accelerator cable is not allowing full range on the holley.
Must be on a chassis dyno if your throttle cable is being referenced. I am curious as to what was done during the engine rebuild to your 351, what were your expectations, and what, in fact, did the chassis dyno record at the rear wheels, at what RPM? Again , just curious
 
Best thing to do is externally charge the battery overnight. Some auto parts stores rent battery testers. These actually put a resistive load on your battery to check its capacity and will indicate good fair or weak.....or you can take it in to your local parts house and have it tested there.....along with your alternator. Quick tip....after you've started your engine, remove the positive cable from the battery. IF the engine keeps running, your alternator is fine. If it dies, bad alternator. Grounding. Make sure your block is grounded to the frame and then to battery negative. If your connections are loose, you'll have trouble all the way around....especially starting the engine. The starter relay (some call it a solenoid) is not defective if you can start your engine with a jump. The starter solenoid is actually either mounted to the side of the starter or is internal. A solenoid is sometimes called a linear motor so on a starter, the solenoid is the device that causes the starter gear to move into and begin spinning the flywheel/flex plate.
 
If the battery load test is OK and the solenoid checks out OK, next step would be to check resistance on the starter cable from solenoid to starter.
If wire is old & corroded, that could cause issues. Also, would be worthwhile to check the starter motor. If starter itself is corroded, gunked up , rusted, that can create similar issues you describe.
 
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