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Discussion Starter #1
So, this happened.

Last monday was supposed to be a great day: We were finally going to bring our mustang up for examination before getting a title here in the Netherlands.

Let me clear up a few things first: I recently replaced the water temp. and fuel gauges because they were broken. Since I saw that they gave a reading which in my opinion looked OK given the current conditions I took it for granted that they were now working (Stupid me).

The examination centre was about 20 miles down south from where I live meaning that we had to go on the highway for the very first time. We decided to drive 50-60 mph without stressing the engine too hard. Halfway there we noticed that the temperature gauge gradually was increasing to hot. Once it reached hot we decided to stop, let it cool and check if anything was wrong. First thing I noticed was that our radiator was overflowing hot coolant through the radiator venting tube on the ground. Our fans (2x SPAL 13A, 1x SPAL 11A for tranny rad cooling) were spinning too. We did add extra coolant last saturday so I had a feeling it was related to that, hence we decided to continue driving.

About 5 miles further we had to take a turn and merge into another lane so we gave a little more gas and that's where everything went south. We heard a loud bang coming out of the exhaust followed by another bang which we have not yet determined. "Luckily" I made a video while it happened:

After this we were forced to pull over and check for any leakage or broken stuff (such as melted fuses), since we didn't find anything wrong we decided to crank it again but no luck. So we had to tow towards the examination centre, once we arrived we were not able to make it start again EVEN with a battery booster the starter was not able to make it run. As dissappointed as we are we had narrowed the issue down to not having a spark coming from the coil. We did notice some of the coolant sprayed over the engine block.

My theory while driving back (we got picked up) was that some of the coolant sprayed over the magnetic pickup connector causing a short in the distributor thus not triggering the electric ignition controller.
Once home I ripped out the electric ignition control and started debugging the issue with the troubleshooting guide made by MSD. I was able to generate a spark using a jumping wire:
Which leds me believe that something is up with the distributor itself. While doing some research I saw some horrific cases where the distributor gear on the cam was totally shredded. I certainly hope this is not the case for us. Next thing I will do is take off the distributor cap and maybe the distributor as a whole. Does anyone have some advice on what I should do? Is a whole engine teardown and rebuild required?

The setup we are running is as follows:
MSD 6AL-2 ignition control (MSD 6421 MSD 6AL-2 Ignition Control)
MSD 8478 Ford 351W Street Pro-Billet distributor (MSD 8478 Ford 351W Street Pro-Billet)
Holley 4781C 850CFM Double Pumper carb (Holley 0-4781C 850 CFM Double Pumper Carburetor)
351W block with Trickflow aluminium cyl. heads[/MEDIA]
 

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It certainly sounds like coolant sprayed into the ignition system and shorted it out.
My question is why would you put an 850 DP on a 351? Unless it's a full race engine that"s way too much carb.
 

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Discussion Starter #5
It certainly sounds like coolant sprayed into the ignition system and shorted it out.
My question is why would you put an 850 DP on a 351? Unless it's a full race engine that"s way too much carb.
We bought it like that and since it ran just fine we never bothered to change it. I was aware it is too big, but what are the actual cons? I haven't noticed any so far.
 

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If you decide to change ignition systems I'm a big DuraSpark fan. Factory Ford and easily adapted to early engines.
 
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Well. I've been running an MSD 6 box, MSD coil, MSD wires and a pro billet MSD distributor for years without a hitch. I do believe there was a period of time when MSD was having problems with their electronics but I don't know what period of time that was. It may be that they are not making stuff to the quality level that they once were but I don't know since I've never had any problems.

My old MSD 6 in fact got so old that the red paint started to peel off due to the box oxidizing under it so I did this to mine;


When you have a mysterious bang come out of the engine like what you had it is probably a good idea to check everything you can think of to check. The backfire might have been the distributor module frying its brain or shorting out.

It is also possible that the distributor turned due to the hold down bracket being a bit loose. That could throw the timing way off and it might still run that way and run hot. If it slings the distributor around enough that would cause a back fire.

I assume when you said it wouldn't crank that you were actually saying that it would crank over but not start? If the engine is bound up and won't move at all you gotta bigger problem.
 
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The remove a distributor you simply remove the cap, unplug or unhook wires and hose, remove the hold-down bolt and retainer and pull the distributor up and out. Putting a distributor in correctly is not as easy...

You can check if the distributor is loose by trying to rotate it with your hand. It should be too tight to turn.

The cons of having a racing carburetor on a normal engine are the car will run badly, use too much fuel, be hard to start and maybe wash the oil off the cylinder walls leading to wear. It was a bad idea by a previous owner.
 

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Actually you can have a larger cfm carb and it run just fine. The cfm of the carb does not indicate that its jetted incorrectly. You could lose a bit of low end torque because of it. But honestly its the least of your concerns at the moment.

It sounds like you've destroyed the distributor gear but that usually takes a bit more time. Although if I remember correctly there is a member here that had a bad gear on his new distributor.
 

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Discussion Starter #10
If you decide to change ignition systems I'm a big DuraSpark fan. Factory Ford and easily adapted to early engines.
Well. I've been running an MSD 6 box, MSD coil, MSD wires and a pro billet MSD distributor for years without a hitch. I do believe there was a period of time when MSD was having problems with their electronics but I don't know what period of time that was. It may be that they are not making stuff to the quality level that they once were but I don't know since I've never had any problems.

My old MSD 6 in fact got so old that the red paint started to peel off due to the box oxidizing under it so I did this to mine;


When you have a mysterious bang come out of the engine like what you had it is probably a good idea to check everything you can think of to check. The backfire might have been the distributor module frying its brain or shorting out.

It is also possible that the distributor turned due to the hold down bracket being a bit loose. That could throw the timing way off and it might still run that way and run hot. If it slings the distributor around enough that would cause a back fire.

I assume when you said it wouldn't crank that you were actually saying that it would crank over but not start? If the engine is bound up and won't move at all you gotta bigger problem.
You are correct. Let me rectify myself here: It was unable to start but it does crank yes.
 

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Discussion Starter #11
i am in the garage as we speak and I pulled out the distributor only to find a severly damaged gear, I will post some pictures in a bit.
761408
761409


I know I need to clean and filter out all of my oil now. But do I need to rebuild my whole engine now because of the debris?

Also: Do I need to buy a new distributor or can I just replace the gear? I'm not sure how to test whether the distributor is still alive.. Some tips?
 

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I've had this happen before. You need to inspect the condition of the gear on the cam that meshes with distributor. When this happened on a friends car, he was able to only repair gear on distributor. Cam was fine. Changed oil, inspected oil pump and replaced it. Engine was OK. You need to inspect carefully. Possibly look at a bearing cap when you have the pan off. It is a gamble...
 

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Maybe the picture is deceiving but it looks like the socket for the oil pump driveshaft is misshapen? Take a good look at the cam gear, spin the engine by hand through two revolutions to make sure the cam gear is good and there are no pieces of distributor gear stuck in it. I'd probably drop the pan and clean it out. No this shouldn't need a complete rebuild.
 
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What kind of cam are you using? Making sure you are not running a billet core which requires a steel distributor gear instead of iron.
 

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Discussion Starter #15
Maybe the picture is deceiving but it looks like the socket for the oil pump driveshaft is misshapen? Take a good look at the cam gear, spin the engine by hand through two revolutions to make sure the cam gear is good and there are no pieces of distributor gear stuck in it. I'd probably drop the pan and clean it out. No this shouldn't need a complete rebuild.
Cranking the engine using the starter would achieve the same result I'm assuming, so that works just fine luckily.
 

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Discussion Starter #16
I've had this happen before. You need to inspect the condition of the gear on the cam that meshes with distributor. When this happened on a friends car, he was able to only repair gear on distributor. Cam was fine. Changed oil, inspected oil pump and replaced it. Engine was OK. You need to inspect carefully. Possibly look at a bearing cap when you have the pan off. It is a gamble...
I will check, remove and clean the oil pan and pump. Any suggestions on how to test the condition of the gear on the cam?
 

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Discussion Starter #17
What kind of cam are you using? Making sure you are not running a billet core which requires a steel distributor gear instead of iron.
We have not done any work on building the engine, this was the way we bought it. What's a good way to determine what kind of cam we have?
 

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A flash light down the distributor hole should show you the cam gear condition. Maybe you'll luck out and the cam is hardened steel on the gear and survived.
 

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You need to rotate the crankshaft with a ratchet and a 15/16" socket while looking at the cam gear in the bottom of the distributor hole. As the cam rotates look for any chipped or broken teeth on the distributor drive gear.
You can also use a 5/16', 6 point, deep socket to see if you can turn the oil pump. The pump may have sucked up a piece of debris that got jammed in the gerotor and locked up the pump which locked up the distributor which sheared the teeth on the driven gear.
 
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