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Hi all. I have a 66 Fairlane with a 289 and she will not start. Short background: Had her out last week and she ran fine. Parked in the driveway and shut it down, and then she would not start again. After investigation, found out my Pertronix distributor crapped out so i put in the old stock distributor. After setting timing from TDC, i am getting spark, have fuel pressure, but will not turn over. I think i am getting some combustion because i hear the exhaust making noise. I even tried advancing timing and then retarding and still nothing. The gas tank is pretty much full and the gas is maybe 2 weeks old.

Im no scientist, but i thought gas+spark+compression=ignition! Apparently not.

Some more details, i am running a Flame Thrower coil and have bypassed the resistor wire, so thats not an issue. She is pretty much stock outside of headers, Edelbrock 650 and performer intake.

Anything i am overlooking??? I feel like i am missing something simple. Please help!
 

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Welcome aboard and what do you mean by "it will not turn over"??:frown2:

Is it Hydro-Locked and the engine is locked up.....cannot rotate the crank shaft ??:surprise:
 

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Timing chain jumped.

If it still has the original stock chain and nylon gears, they will often jump on shutdown.

You say,

but will not turn over
Do you mean it won't crank?
Or do you mean it won't fire?

You say,

i thought gas+spark+compression=ignition!
Did you actually check compression?

I learned this as...

If you have spark and fuel and no mechanical problems,

then it should fire.
 

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Discussion Starter #4
Sorry, she turns over, crank moves with no problems. But will not fire. Timing chain huh?
Did not check compression. The engine has run fine for a long time. Not sure if compression would all of a sudden be an issue.
 

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Sorry, she turns over, crank moves with no problems. But will not fire. Timing chain huh?
Did not check compression. The engine has run fine for a long time. Not sure if compression would all of a sudden be an issue.
Yes, timing chain.

Check compression, that will tell right away if the chain skipped.

When the chain jumps, compression will be very low to non existent.

A good experienced ear can tell from the sounds the engine makes when cranking, if the chain skipped.
The engine will make weird wheezing sucking noises that are different from normal intake and exhaust noises.
 

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Discussion Starter #6
Ok. That sounds logical. Ill check compression next. For a fairly stock motor, what should i expect for compression?


Ive read on other forums that if i advance the distributor about 10 degrees and it starts, then its probably skipped. Can the engine continue like that? Or will the chain need to be replaced?
 

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After investigation, found out my Pertronix distributor crapped out so i put in the old stock distributor. After setting timing...

When you put the stock distributor in, are you sure cylinder #1 was at TDC _of the compression stroke_? Otherwise it could be off by 180 degrees. A simple thing to check before replacing the timing set.


Pat
 

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Discussion Starter #9
Yes, i checked TDC multiple times and even flipped it a few times. After thinking about it, i believe the rotor was in a different position each time i took off the distributor cap, which means the timing chain is slipping gears. Im going to check the compression, timing chain play, and timing next to confirm that the gear is the problem before tearing it open.

Thanks for the info.
 

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Ok. That sounds logical. Ill check compression next. For a fairly stock motor, what should i expect for compression?


Ive read on other forums that if i advance the distributor about 10 degrees and it starts, then its probably skipped. Can the engine continue like that? Or will the chain need to be replaced?
As said above, approx 100psi compression.
IF the compression check shows that the chain skipped,
do NOT attempt to start the engine by messing with the timing.

It will skip again and could cause severe engine damage if it hasn't already.
Valve to piston contact is not pretty.

Whoever gave you that advice on the other forum, is not very smart.
 

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When the timing chain jumps, the cam/distributor timing get behind. From working on old worn out engines back in the day, if the timing chain jumps, you'll often be able to start it by advancing the timing a lot. (Sometimes, you have to move all the plug wires one spot clockwise.)

The above doesn't mean I recommend it, as it still won't run right. It's just something that will often get you home in a pinch. And, yes... there is a chance it could jump some more, and run the pistons into the valves, which is an expensive repair.

That being said... As was said, do a compression check. If you have a baseline, this can tell you if the chain has jumped. When the chain jumps, the cam timing gets retarded, which decreases cranking compression. The difference in cranking compression should be fairly obvious... especially if it has jumped more than a tooth. If it has jumped very far, there often won't be enough compression to start the engine.

If you have 120+ psi, it's probably not the chain... unless advancing the distributor allows it to start, as that's a pretty tell tale sign.

Good Luck
 

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I've messed with a lot of motors and never saw a timing chain jump a tooth......not saying it can't happen but I'd think a motor has to be worn VERY BADLY for it to happen??:surprise:

My guess is the OP put his old distributor in and set TDC on the exhaust stroke.......maybe??:frown2:
 

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I've messed with a lot of motors and never saw a timing chain jump a tooth......not saying it can't happen but I'd think a motor has to be worn VERY BADLY for it to happen??:surprise:

My guess is the OP put his old distributor in and set TDC on the exhaust stroke.......maybe??:frown2:
Until he reports the results of the compression test, we can't be sure if the chain jumped or not,
but it is a very real possibility if the engine still has the *stock* timing set.

Are you not familiar with Ford's stock "silent" timing chain and gears?

During the 60's and maybe into the 70's Ford made timing sets with nylon coated teeth on the cam gear.
Presumably for "quiet running" cam drive.

Those nylon teeth wear relatively quickly. The nylon also "disintegrates" from the constant heat/cool cycle.

I have personally experienced 4 different encounters with Ford engines that jumped the chain because of those worn stock nylon gears.
I say personally, because I was involved in fixing all of these failures.

1. On my buddy's 67 Galaxie 289
2. On my own 65 Mustang 289
3. On a friends 68 Shelby 428 CJ
4. On a 66 Fairlane 289

On all but 1 of these, the chain jumped on engine shutdown and would not restart.
On my personal 65 Mustang 289 it jumped while I was driving when I gave a hard throttle hit,
and all of a sudden the engine began to run really bad.

Once I shut it off it would not restart.
At the time I already had experience with a jumped chain, and I knew immediately what happened.

Replacement "factory type" nylon gears were also available at one time,
but most folks that I know used the all steel replacement sets. No more nylon teeth to strip.

Obviously you have not been around all that many stock engines from the 60's.

Stock nylon cam gear....



Damaged nylon gear...



Here's a good one.... :wink2:



Oh, and by the way.... One more thing to worry about...

Where do you think all those chunks of broken nylon end up?

Ya, in the oil pan....

....and if they happen to get sucked into the oil pump... because the screen has a tear...

They lock up the pump and twist the distributor gear and shear off the roll pin....

.... and that leads to no oil pressure...

Not a nice thought, hey?
 

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in 74 i had a 67 gto i drove from mississippi to california. when i pulled into my dads driveway istalled it. wouldn't start again. same thing; nylon teeth gone. that was the only thing that broke.
i have seen the twisted oil pump drive from the valve guide seals being sucked up the oil pump
 

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Discussion Starter #16
I will check compression when i get some time. Traveling this week. Is it dangerous to turn the engine over if the timing is off that bad? I dont want valves to bend.
Also, i recently changed the oil, would there be nylon chunks in that, or would they all rest at the bottom of the pan?
 

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*IF* the timing is badly off... then YES it is dangerous to turn or crank the engine over.

You can turn it carefully by hand (socket on the front crank bolt)
and if there is piston to valve contact, you will feel it.

If piston to valve contact has already happened, then its all too late.

I assume you have already been cranking it to attempt to start,
so go ahead and do the compression check.

*Some* of the nylon chunks *might* come out the drain, but unlikely all of them would.

More likely they all stay in the pan... :(

For the record; all 4 of those others I worked on with jumped chains, we just left the chunks in the pan.
We got lucky.

There is a screen on the pump pickup and luckily all 4 never had a problem after the new timing set.

I only mentioned it as a "possibility" of what can happen...

If your luck is anything like mine... well...

Also FWIW, I have torn down quite a few 60's engines and found those chunks in the pan,
but they were not the reason for tear down.

Those engines were just ready for rebuild anyway. (lotsa miles)
On those the chain never skipped and the chunks never locked the oil pump.
 

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If you're worried about piston to valve interference, roll the engine over by hand first before using the starter. You'll need a 15/16 ratchet wrench. Turn it like you're tightening the bolt. If you hit solid resistance, stop. If it rolls over freely for several revolutions, you should be able to use the starter motor to check cranking compression.

Good Luck
 

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You might also check the roll pin on the distributor. They have been known to fail. It would also cause the rotor to change position.
You mentioned "fairly stock". has the engine ever been apart or just had external add ons? If it has been apart , the timing chain is usually replaced and rarely with another nylon gear.
Randy
 

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You might also check the roll pin on the distributor. They have been known to fail. It would also cause the rotor to change position.
You mentioned "fairly stock". has the engine ever been apart or just had external add ons? If it has been apart , the timing chain is usually replaced and rarely with another nylon gear.
Randy
The roll pin doesn't generally shear... unless something causes it to shear. That something, is usually debris getting caught in the oil pump, locking it up. When debris locks up the oil pump, either the pin will shear and/or the driveshaft gets turned into a Twizzler. As a Ghetto Repair, you can often spin the oil pump in the opposite direction with a oil pump priming tool to eject the debris. It's another one of those tricks that might get you home, or something to do with an old worn out engine you have zero inclination in repairing properly. lol

Ideally, if there is a sheared pin or twisted drive shaft... You pull the pan, clean/replace the oil pump, replace the pickup, clean the oil pan... and install a new timing chain (if it feels loose). You can check the timing chain by turning the engine over frontwards than backwards, checking for slack. The timing chain part can be a lot more work added (depending what all is on the front of the engine), and is most important if you're dealing with the stock, old nylon gears.

Good Luck
 
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