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*trying* to restore a 72 mustang - cranks, doesn't start

This thing is a piece of work. The previous owner took out the Cleveland engine and dropped in a 460. I suspect the wiring is a little out of whack, but I was able to get the electrical system hooked up enough to crank the engine. When I turn the key, I hear a sound like the engine wants to start, but it doesn’t (sort of like a weak battery…but I just put a brand new one in).

Could this be the starter motor? Possibly no fuel getting pumped in? (Before anyone suggests the obvious…I put a few gallons of gas in it already).

I’m an accountant pretending to be a mechanic, so any guidance would be VERY much appreciated! Feel free to poke fun as well…I’m a good sport.

Just give a quick squirt of starting fluid down the carb. If it starts, there’s a fuel problem.


Take the air cleaner off. Look down the carburetor while operating the throttle linkage. You should see fuel squirting into the middle of the primary (front) venturis. No fuel? Find out why, like maybe a failed fuel pump.

Fuel’s there? You’ll need a voltmeter. Check the voltage from the POSITIVE side of the coil to the NEGATIVE battery post with the key in the “on” position. You should read 12 or so volts. Then check the NEGATIVE coil terminal to battery NEGATIVE. With the key in the “start” position, with the starter cranking the engine over you should see some value lower than 12 volts.

Do this stuff and report back to this post.

I assume you have checked to make sure there is spark getting to the plugs. If you have spark and Tester’s suggestion of using starting fluid doesn’t make it fire up then mark the position of the distibutor. Then try adjusting the disty while cranking the engine to see if the timing is off slightly. If that doesn’t work then there is most likely a valve timing problem.

Is the new battery large enough to turn that big 460? Try what Tester, Jay and Cougar suggested and post back. I’d clean the plugs, clean the rotor and cap contacts (until I got it running, then get new stuff), mark then loosen the distributor, and then put a second battery on it (jump start it), squirt starting fluid down the carb throat, and crank it. Keep the butterfly open on the carb with a screw driver while you crank it, and when it begins to run, adjust the distributor until it starts to run better. Rocketman

Thank you everyone for your suggestions so far. I will try everything here as soon as I get back to my garage in a day to two. I’ll post results shortly. In the mean time, feel free to keep the suggestions rolling!

THanks again!!

Something I just though of…

Rocketman, you asked if the battery was big enough to crank the 460. WHen I went to AutoZone, I told the clerk the original engine was the 351 Cleveland. Is it likely that alone could be thr problem? Just not enough “juice” to crank the larger engine? And I can put another battery in there…you suggested jumping…does that mean jumping the car in the classic terms, as in actually hooking jumper cables from my regular vehicle to the battery in the Mustang?

Thanks again.

Yes! Get more “juice” to the ignition system . . . so you can turn that big old 460. Can you take the battery back for an exchange of the proper one? I know you said that you’re an accountant . . . did you keep the receipt? Rocketman

Try again tomorrow and it might just start. Check the negative battery cable for oldness. If it hasn’t enough youth, it must be corroded. If the rubber is crscked, it’s no good. Test it? Connect a jumper cable to a metal part on the engine and the other end to the negative terminal on the battery. If the starter cranks faster, change the cable.

Ah yes! Receipts, receipts, receipts! How many amps do you think I need? Is it the “Cold Cranking Amps” that I am concerned with? I see one that has 800. You think that should be sufficient? I’ll be back home tomorrow, so I’ll be able to go through the procedures listed in this thread. I’ll report back soon!

Check the Ballast resistor/wire too, it’s easy to overlook.

Ed B.

I have no idea about the amps you’ll need to turn that 460. I’m a college professor who used to be a mechanic, years and years ago . . . in the 1970s and early 80s! Ask the folks where you bought the battery if the 800 you have is for the original 351 or will it work for your 460. I’d be willing to bet that your battery is too small. Don’t jump the battery if you have a chance to take it back for a bigger one, get the bigger one and try that first. Most electrical parts are not returnable, I believe. Rocketman

“The previous owner took out the Cleveland engine and dropped in a 460.”

460’s don’t just “drop in”… What kind of ignition system is being used? Points?, Motorcraft electronic, Aftermarket electronic? Have you checked to see if you are getting ignition spark? Remove the coil wire from the center of the distributor and hold it near (1/2") any metal and have someone crank the engine. You should see nice fat sparks jumping off the end of the coil wire…

BTW . . . what kind of '72 Mustang? What kind of shape? I used to have a '68 Fastback, and then a '69 Torino, easy stuff to work on, but the worst rust buckets I ever owned. My best friend back in the day was the Son of a Ford Dealer . . . and I worked for a Mopar Dealership . . . so I either had a Ford or a Mopar in those days. I kinda remember fixing just about every part of those old cars at one time or another. The good old days? Rocketman

True, it probably was not “dropped in,” but rather pushed, prodded, choked, squeezed, hammered, and shimmied in. Those cars have a ton of room under the hood, but am definately feeling the pain of the enormous engine. You should have seen me trying to squeeze the brake booster in there!

Also, Rocketman, it’s a Mach 1 fastback. '73, not a '72.

If it was a Cleveland, it was the same size as the 460. The Windsor engine was the small block. A 700 cca battery will be able to crank a 460; it used to crank with less. I think it is an 8.5 to 1 compression ratio engine.

OK everyone who has offered suggestions, here is my report back:

Tester: I sprayed starting fluid down the carb. Nothing.

JayWB: Fuel does not squirt down the carb. It’s completely dry. I checked the voltage and it reads 12.5v.

Caddyman: I took the coil wire off of the distributor and saw a spark when I turned the ignition. It was not as grand as I imagined, but then again, I wasn’t sure what to expect. Maybe it was normal, but at least there was a spark present.

pleasedodgevan: The 460 is quite a bit larger than the Cleveland. It’s 2" wider, 4" longer, and an inch higher…plus it weighs an extra 150 lbs.

Soooooo, does this, in everyone’s opinion, point toward a fuel pump issue? Possibly completely non-functional? I traced the fuel line from the tank to the pump and it looks as though it is all connected. Is it possible to start (even for a second) with starting fluid if there is absolutely no fuel getting to the carb?

Thanks again.

Starter fluid should give it a short rev, try opening the choke and spraying the fluid directly in the carb, (Caution fire hazard). Did the engine run in your experience? you can remove a plug attach the wire, ground the plug to the engine block and see if you have spark there. (do not hold plug shock hazard) and make sure starting fluid has dissipated, if spark is good at the plug it’s and a few attempts with starting fluid doesn’t work then check timing, or improper plug wire connections, re firing order. No spark at plug check points, rotor cap etc.

It usually isn’t a good sign when spraying starter fluid into the intake doesn’t help the engine want to fire. It appears you have spark, though you haven’t tested it all the way through to one of the plug wires. You also need to see why fuel isn’t getting to the carb but the starter fluid should have still worked. It sounds like you have good compression since the motor isn’t turning over real easy but a compression check of all the cylinders would be a good thing to do and know where you stand with each one.

Here is a link that may help you for the firing order of the engine. See if that matches your current setup. If that is good then trying moving the disty as I stated earlier.

I agree with Cougar here . . . starter fluid down the carb throat and cranking should produce something. Go back to basics . . . first, go over you ignition system and make certain that you are getting good spark to the plugs. If you know the wires and other stuff are OK, move on. If not, change them if any parts are suspect (this IS a project car anyway, so you’ll be keeping it and any $$ you put in will benefit you). Spark testers are cheap, less than $15, get one and use it. If the spark comes back OK, then move on to the fuel. The pump is easy enough to test . . . if electric or mechanical, you can “jump” it to make it work, check for fuel output. Check the fuel filter also. But as Cougar suggests, your results with the starter fluid points away from fuel, more toward spark and or timing. Learn how to do it and run through the basics of the electrical system and timing. It’s fun, you’ll never forget it, and you’ll feel great when you solve it. My bet is on weak spark or bad timing. Rocketman