Engine won't start

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FL72Sprint

Member
Joined
Jul 1, 2019
Messages
8
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0
Location
Florida
My Car
72 Olympic Sprint 302
I recently picked up a 72 coupe with a 302 engine.  The previous owner began repairing the car after an accident.  Damage was pretty much only to the front end (up to the radiator / support).  The car was "running when last moved".  However, I'm not sure exactly how long since that supposedly was.

When I've tried starting it, it will turn over.  I will sometimes hear a popping sound (timing issue?) and other times where it seems to almost start (on a cylinder or two).  There has been a few times where it has actually started for 1-2 seconds.

Since I've had it, I've replaced a majority of the overall mechanicals.  Within the engine bay, I've replaced pretty much everything outside of the block itself and it's internals.  I've replaced the radiator, water pump, thermostat, distributor (plus wires and plugs), fuel pump, carburetor, oil pump, coolant and fuel hoses, starter, alternator, and p.s. pump.  I might be leaving a couple things out.  I've also replace the fuel tank and lines.  All these were replaced due to the condition of the installed ones.

Fuel is definitely getting to the carb.  The distro went from double to single vacuum, so I'm not 100% on the vacuum system.  I found a diagram of a single vacuum on here somewhere, but I can't find it again.  There's also a couple wire connectors coming off a wiring harness near the distro/#5 cylinder.  I'm not sure if they were ever used since nothing is really around the area they can reach.

I also thinking it could be a compression or timing issue.  However, I don't have the proper tools to test either of those.  

I can provide pictures (or wonderful hand drawings) if needed.  Any help is appreciated.

Thanks,

Matthew

 
Make sure cyl 1 is at btdc, with compression (no matter how good). align dist (pointer and cap) and check CCW fire order on wires.

Then you really need to get yourself a timing light...

 
+1 on the timing light and on the distributor alignment and firing order. Very difficult for a novice mechanic to get it running right without a timing light.

Are you getting spark when the engine turns over?

You need to find out what the wires are for. You can download the wiring diagram under the Mustang Data tab at the upper right of this page or post the wire color codes and pictures of the wires so someone on the forum can help you with them.

 
As mentioned above you will need a timing light to get it running right. It does sounds like is a timing issue. You mentioned that you are getting fuel so the thing to try for now is first see if you are getting a continuous spark. Pull any plug wire and have someone turn the engine over for a few seconds. See if you are getting a repeating spark. If not, then you know you have a electrical issue. This could be anything from the coil to the distributor. If you are getting good repeating spark then move on to finding TDC on number one cylinder.

Do this by removing the #1 spark plug and using your thumb plug the hole. Have someone tap the engine until you feel the compression stroke. Use a breaker bar to finish turning the crank until you get the cylinder dead top. Check the timing marks on the harmonic balancer and make sure the pointer is at the TDC mark. Next, pull the distributor cap and see if the rotor is pointing to #1 on cap.

The rotor turns ccw so it should be a smudge after the contact on the cap with #1 on tdc . If not, loosen the distributor and rotate it until it is at least pointing to #1. If it is way off then you might need to pull the distributor out enough to advance or retard it a tooth on the gear. At this point the engine should fire and try to run. You may need to turn the distributor a little to get it running smooth. You will now definitely need a timing light to finish setting the timing. If still no luck then you may have a timing chain, cam or valve issue among other things. Good luck.

 
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Thank you all for the responses.

I get continuous spark. I’ll try adjusting the cylinder and distributor. The timing blade (not sure correct name) is present on the block. However, the timing marks on the balancer are gone due to rusting. I can feel the piston in #1 when it comes up. If I turn the shaft until it stops moving up on the compression stroke, would that get me close enough before a timing light is needed?

Also, does going from a double to single vacuum affect anything assuming all tubes are routed correctly?

 
It shouldn't affect anything. However, I wouldn't connect the vacuum until you get it running. Just make sure all the vacuum ports and hoses are plugged.

The timing marks are engraved into the balancer, so it just needs some wire brushing to expose them.

Yes, you can adjust the distributor so the points begin to open when the #1 piston is at TDC (top dead center). Make sure the rotor is pointing at the #1 terminal/spark plug wire. It may be easier to determine TDC with a piece of soft copper wire inserted into the spark plug hole. Do not use something that will scratch the cylinder walls or break off in there.

 
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As Don said, clean the balancer to find the marks.  Not for sure of your knowledge level on this but the are 3 different TC's  There  is BTC "Before Top Dead Center", ATC "After Top Dead Center" and TC " Top Dead Center.  Make sure you are on the TC mark when checking the rotor orientation to #1.



 
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I’ve been trying to get the distributor off and it’s not coming. It’ll still turn with the cam so it’s not bound up that way. Both the distributor and oil pump are new. When I removed the old distributor it only took minor convincing. There wasn’t any issues getting the new distributor in.

I’d prefer not having to go all the way down to the timing cover, but it’s looking like I won’t have a choice. Any ideas?

Thanks

 
Pulling the timing cover won't help with pulling the distributor out. You can't change the distributor timing there. The relationship between the crankshaft and camshaft has to remain where it is.

Can you rotate the distributor when the clamp is loose? Will it move up, even a little?

 
I know timing can’t be adjust under the timing cover. I meant to pull the cover in order to get to the bottom of the distributor shaft.

It will rotate a bit with the clamp loose. Only the housing will lift slightly, maybe 1/8 inch. There is no upwards movement on the shaft. I’ve pulled/pried about as hart as I’m comfortable doing, it being cast aluminum.

Is it possible it somehow got bound/stuck to the oil pump shaft?

 
Question - Is the rotor off on #1 contact when #1 cyl is tdc? Try to rotate the rotor ccw while pulling up on the distributor. Try using a block of wood under the distributor to pry up with while you try to turn the rotor. When you replaced the distributor did it go in hard when you were tightening the hold down clamp? It would be hard to jamb the oil pump shaft in the distributor unless you got some dirt or debris in the end of the distributor shaft. Should come out with a little persuasion.

 
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It's possible the oil pump driveshaft could twist in the socket in the bottom of the distributor shaft, just like an allen wrench can twist and get lodged in a socket head bolt. This would require the driveshaft to be worn or the oil pump stopped turning. You said you installed a new oil pump, is it a high volume high pressure pump? If installed correctly the one-way retainer washer on the oil pump shaft would allow only a small movement upwards of the distributor if it is jammed in the distributor shaft. If the oil pump driveshaft did twist in the distributor shaft I would also expect the bottom of the distributor shaft to be damaged, possibly split.

 
Oh joy, I believe fun times are ahead.

The new oil pump is high volume. Is that fine or should I get a regular flow? As far as I know it’s the original engine, which is why I went with high.

I pulled the timing cover and dropped the oil pan. The oil pump and shaft came off just fine. However, the distributor still won’t come out. I think the camshaft might need to be replaced. Once I can get the distributor out, I can verify. There are metal pieces in the oil pan, which I know recently got in there. When I turn the crank/cam to certain spots, the distributor shaft will spin freely, even though the two gears should still be meshed.

If the cam is missing teeth on the worm gear, can I just replace the cam or should I check/replace other internals?

 
The high volume oil pump puts a large additional load on the distributor drive gear.

Because it wasn't running when you stripped the distributors gears, it may not have blown metal filings all over the crankshaft and rod journals. However, because you already have the oil pan off I would pull a couple of rod caps (1 & 5) and the number one or two main cap just to check the bearing and journal conditions. While you have the timing cover off check the free play of the timing chain.

 
Will check those items.

But I think the metal came from the cam. From what I can tell right now, the teeth on the distro shaft are intact.

 
Run a standard volume pump, HV is not needed and can cause other problems. If the teeth on the cam look good, then I'd leave it be.

Since you have the pan off, you should be able to drive the distributor up and out of the block from below.

 
Finally got the distributor out. Had to pound it out from the bottom. Not sure what caused it to get stuck. The teeth on the distro looked fairly ok. However, the cam has definitely lost a lot of teeth. Here’s a picture of what I found in the oil pan. Could any of this come from anything but the cam?

Since the cam certainly needs to be replace, how hard is it to do? From the Haynes guide and online, it sounds somewhat straight forward. Looks came be deceiving though. I know there’s a lot of attention to detail, what part comes from which cylinder and the direction, etc. is it time to call I’m the pros? Time to complete doesn’t bother me and being in electronics repair by trade, I’m used to tracking where/how thing come from.



 
Not looking good. First questions is what caused the gear on the cam to fail. Did oil pump lock up causing distributor shaft to freeze? Or was the distributor not seated all the way? Also send pic of distributor gear too. Don't know what you are calling "fairly ok" is. Could be asking for more problems if you reuse it.

I would either pull the pump and check it or get a oil pump priming tool and make sure the pump is working ok. I would also do a very through check of all the internal parts while you have the pan off. Check the rods, caps, mains and all surfaces of the block for an damage or missing pieces.

That aside, replacing a cam for a novice can be somewhat overwhelming. Overall it is not that difficult just labor intensive. NOTE that if not done properly could cause major engine damage - valves and pistons. The main thing is to follow all instructions and don't take any short cuts.

If you do it yourself MAKE SURE you get the cam and crank alignment RIGHT. There is no room for any error here. Also will need to break the cam in - something the newbies over look and cause failure of the cam lobes. Plenty of support here on the site to help guide you if you decide to do it.

 
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[Time to complete doesn’t bother me and being in electronics repair by trade, I’m used to tracking where/how thing come from.]

As you are familiar with repairing things, you need indeed to take your time and do it right. It's not complicated, but needs be done right.

If the engine is not yet out of the car. I'd say buy an engine stand, you're going to need it.

Even if a cam change would be the only thing required, with so many metal bits, you do not want to inspect the engine while in the car...

Also, make tons of pictures while you are busy.

 
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