Superperformance - Having engine trouble - need help

DownTown · #1 (**permalink**) 07-26-2018, 12:04 PM

So I was out driving yesterday after the car sat for nearly a week and the car ran fine for 20 - 30 minutes. I stopped and started it twice and then on my way home it just loss power. So after towing it home, I tried to start it. All it does is crank but it seems as though I don't have any spark to kick it over. Fuel is pumping to the carbs, so I know I have fuel, it's just dropped dead on spark. I have all electric devices working and battery is well above 14 amps, headlights work, fans work, blinkers, brake lights, etc.

I just need some insight on where to start looking to problem solve this.

Roush 427 sideoiler, with MSD distributor cap. I checked all the spark plugs are tight and in place and the distributor cap is tight. All battery cables are tight, all electrical connections to the Holey Carbs is hooked up.

DownTown

1966Snaake · #2 (**permalink**) 07-26-2018, 12:21 PM

My first guess is a bad MSD (Might Shut Down) module. I personally do not own one, but fellow drivers have found themselves on foot because of this.

patrickt · #3 (**permalink**) 07-26-2018, 12:25 PM

MSD units are very easy to test to see if they are making a spark. Do that first: https://www.msdperformance.com/suppo...ng_techniques/ That's the first step. If you're making a spark from the coil, then the next step is see if you're getting sparks at the spark plugs, but first things first.

DownTown · #4 (**permalink**) 07-26-2018, 01:02 PM

Alright let me check there first and get back to you guys, thanks for the insight.

pgermond · #5 (**permalink**) 07-26-2018, 01:56 PM

Dollars to donuts its the magnetic pickup.

tortuga · #6 (**permalink**) 07-26-2018, 03:47 PM

Quote:

Originally Posted by pgermond

Dollars to donuts its the magnetic pickup.

I had one that looked like it had been on the sea floor since the war...

I pull the cap periodicall and check mine now...

pgermond · #7 (**permalink**) 08-07-2018, 06:01 PM

Quote:

Originally Posted by DownTown

Alright let me check there first and get back to you guys, thanks for the insight.

Did you ever figure it out?

Jim Vander Wal · #8 (**permalink**) 07-27-2018, 03:50 PM

Downtown,

You don't indicate your chassis number, would help.

An ignition box (MSD or otherwise) is usually mounted in the engine compartment on top of the passenger side foot box or in the passenger side foot box forward of the dash.

In case you don't know the box is about the size of a hardcover book, can't hardly miss it and it won't fit behind the dash, or it least I can't imagine getting one in there.

The ignition system does not need the ignition box, it will run with the supplied Superformance wiring.

Cheap plug - order a wiring diagram from Blas, a few post before this. Best investment you'll make for your car.

Jim

patrickt · #9 (**permalink**) 07-27-2018, 03:59 PM

You really can't miss it. Here's a pic of mine, which is tucked neatly under the passenger side of the dash. Of course, I ain't got no SPF....

Note the capacitor. Everyone with an MSD unit should have one.

RockBit · #10 (**permalink**) 07-27-2018, 04:54 PM

Quote:

Originally Posted by patrickt

Note the capacitor. Everyone with an MSD unit should have one.

Patrick - what does the capacitor do?

patrickt · #11 (**permalink**) 07-27-2018, 05:12 PM

Quote:

Originally Posted by RockBit

Patrick - what does the capacitor do?

The capacitor is installed "across" the positive and negative feeds to the MSD box. If it was just a wire it would be "short-circuiting" the two wires. But, it's a capacitor, so once it reaches its fully charged state it stops the direct current going across it but continues to act as a "shock absorber" for direct current voltage spikes, thus protecting the MSD box from them. Plus, if your alternator is leaking AC current out, a capacitor across the lines acts as a short cut for the AC to pass right through and head back home without ever going in to the MSD box to help muck up the electronics.

RockBit · #12 (**permalink**) 07-27-2018, 06:09 PM

Quote:

Originally Posted by patrickt

The capacitor is installed "across" the positive and negative feeds to the MSD box. If it was just a wire it would be "short-circuiting" the two wires. But, it's a capacitor, so once it reaches its fully charged state it stops the direct current going across it but continues to act as a "shock absorber" for direct current voltage spikes, thus protecting the MSD box from them. Plus, if your alternator is leaking AC current out, a capacitor across the lines acts as a short cut for the AC to pass right through and head back home without ever going in to the MSD box to help muck up the electronics.

Great explanation. Thanks. I’ll put one on mine.

tortuga · #13 (**permalink**) 07-28-2018, 06:38 AM

Quote:

Originally Posted by patrickt

You really can't miss it. Here's a pic of mine, which is tucked neatly under the passenger side of the dash. Of course, I ain't got no SPF....

Note the capacitor. Everyone with an MSD unit should have one.

What kind of capacitor? Source?

Seems like a great idea, basically an Ac shunt if I remember from my EE100 class decades ago...

Steve H
SPF 1764

patrickt · #14 (**permalink**) 07-28-2018, 07:03 AM

Quote:

Originally Posted by tortuga

What kind of capacitor? Source?

Seems like a great idea, basically an Ac shunt if I remember from my EE100 class decades ago...

Steve H
SPF 1764

MSD makes it. Part #8830 -- it's just a 26Kufd capacitor, but you have to wire it in correctly or your car won't run at all.

tortuga · #15 (**permalink**) 07-28-2018, 11:11 AM

Quote:

Originally Posted by patrickt

MSD makes it. Part #8830 -- it's just a 26Kufd capacitor, but you have to wire it in correctly or your car won't run at all.

Ordered, thanks for following he tip Patrick!

rodneym · #16 (**permalink**) 07-27-2018, 08:43 PM

It's gotta be on the inside of the firewall, in front of the passenger.
The cap that Pat mentions is a nice bit of insurance. I installed one, along with knurled finger tight screws and a quick disconnect(or) for a road side repair but alas, no issues with the MSD.
Perhaps the Russians?

snapier · #17 (**permalink**) 07-28-2018, 04:57 PM

My Superformance (SPO1400) had the same problem after 2 weeks of trouble shooting I found out that I had a faulty magnetic pickup in the MSD distributor and also a failed Control box that is just under the glove box. This was tuff to troubleshoot because both must have failed at the same time. Good luck.

patrickt · #18 (**permalink**) 07-28-2018, 05:12 PM

Quote:

Originally Posted by snapier

My Superformance (SPO1400) had the same problem after 2 weeks of trouble shooting I found out that I had a faulty magnetic pickup in the MSD distributor and also a failed Control box that is just under the glove box. This was tuff to troubleshoot because both must have failed at the same time. Good luck.

It's pretty rare for two electronic components to fail at the same time without an underlying cause of some sort. Jump starts, misbehaving alternators, flaky voltage regulators, a "fast" battery charge, they can all hasten an MSD demise.

Blas · #19 (**permalink**) 07-28-2018, 06:03 PM

Poor grounding and improper installation are the major causes for MSD failures from what I have seen. Spikes in the wiring are a close second.
Blas

tortuga · #20 (**permalink**) 07-29-2018, 08:31 AM

Quote:

Originally Posted by Blas

Poor grounding and improper installation are the major causes for MSD failures from what I have seen. Spikes in the wiring are a close second.
Blas

So to prevent to the maximum extent the early demise of the Msd box, should a capacitor to shunt spikes and direct heavy ground be run from the box to a very good ground? What else would fall under poor installation?

Thanks