ideas on why it broke down???
 

Today I drove my Cobra in a 4th of July parade. It did really well, never even close to over heating. I was suprised since it is kind of warm today. Well anyway I made it through that and then when along some back streets to try and find my daughter. As I was pulling out of a parking lot it back fired once or twice and then shutdown. I checked and it is getting fuel. There appears to be no breakage in the motor anywwhere. It turns over and it occasionally pops like it wants to start up. Any ideas on what I should look at??

here is what is under there..

395CI small block
Weber IDA-48 carbs
MSD 6AL ignition system
MSD distributor
MSD coil

Make sure you didn't shear the pin on the distributor drive gear. I broke mine twice. The second time i could hardly tell until I took it apart. Get the #1 piston top dead center and see if the rotor is where it should be. First see if the button on the inside of the distributor where the coil wire hooks burned up!
Scott

Make sure your battery is charging, because if it isn't and the voltage drops below a certain # the car will not run with that MSD distributor, as it takes up lots of volts.

What scooter said -- pull the distributor cap and see if that rotor spins

timing changed
 

check to see if your distributor clamp is loose.


Dwight

Sound similar to what I had with my 351 Windsor back in November 2007.
Distributor and Camshaft gear stripped.

Dex....

I would have to agree. MSD strikes again.

Well I pulled the distributor and all looks good.. Gears look good, pin looks good. I tested the trigger and it works.. I am wondering if it is the 6AL itself that has faltered. Is there an easy way to test that???

If you sheared the distrib pin it may show no oil pressure.

make sure you check the coil. It sounds similar to when my coil fouled.

The simple way is to disconnect the coil wire from the dist. and lay it where the contact is an inch or so from a ground (intake/valve cover/block etc. Not near fuel though!) then use a remote starter switch or a helper to turn the engine over. If the MSD is working and you are sure the dist. is good then you'll have a LARGE series of sparks from the coil wire. Before you do that, make sure that you are clear of the wire and arc path because you do NOT want to get hit by that puppy! Yes I do know that.:JEKYLHYDE

Steve

I have had MSD boxes fail with similar results. I have also had an timing chain burp (Jump) with similar results.

The MSD manual can be downloaded here (http://www.msdignition.com/downld1.htm ) Page 9/10 they have a "Checking for Spark" cheat sheet. ---they also have a customer support line. The other thing I would to check is the quality of the electricity feeding the MSD units.

MSD: Customer Support Department at (915) 855-7123, 8 - 5 mountain time.


The other item to review would be if the timing chain has slipped a gear(tooth) this can be checked by popping out the plugs, valve covers and follow the firing order closely.

--Steve

I have had several MSD boxes fail.. on several different cars. They don't like heat. See if you can bypass the MSD 6AL box and get the car to run.

I've had a MSD box fail and leave me stranded. After taking the box apart and observing the quality that goes in one of these, I'll never run one again or anything from MSD. If you have a component in your car that could leave you stranded and you don't need it, then rip it out of the car if you really enjoy driving.

I am betting too that it is the MSD box, they don't like heat at all.

I have started putting all of mine up under the dash away from any heat.

Scott S

That is exactly what I have done to cure that issue. I even mount a small computer cooling fan with it.

MSD distributors are GREAT. But the boxes are really prone to over heating... and cooking themselves.

The MSD tech. told me not to mount it under the dash as they get quite hot and need air flow to keep them cool and that doing so is asking for trouble.

Jim

My SPF came with the Ford Duraspark as all SPF do and then most change to MSD. I have not had time nor the desire to be honest to change mine since my car runs so well. My Ford Duraspark failed at about 20 miles, I went to autozone and picked up a new one for $19.99 with lifetime warranty and plugged it in (about 5 minutes) since then have had zero issues, car runs perfect. I have no doubt the first failure was a case of infant mortality. The Duraspark does not have a rev limiter but I rarely see 5K rpm's anyway. Now I carry a spare duraspark and coil in the trunk (the replacements from SPF) it takes less than 5 minutes to change both, no tools they are both plug and play.

I have to assume the duraspark was used in over a million cars and trucks ford manufactured so the design is proven. Not only that it is $200 cheaper than the MSD and does not buzz like an msd.

Hey every one. I have my MSD box under my dash, and it has never failed in 5 years. so maybe that is a good place for it. The only two times I have ever been stuck because of an ignition problem it has been the distributor gears, once the pin and once the teeth being stripped. MSD distributors are really prone to corrosion under the cap, and I once had a no-start where that was the problem (didn't get stuck that time, just scraped off the crud). I have had an MSD dist with a mechanical advance that got rust in the advance mechanism as well, I car started but wasn't running well. Took me a while to figure that one out.

If you do the jumper test (jump the purple and green wired of the dist as described above) and you get spark, then I would imagine it HAS to be the distributor. Only other possibility is fuel or carb. If you have an electric pump, check the fuel pressure. Maybe check carb floats (stuck float) etc.

I have heard stories about bad MSD units. My new policy is that I carry around a small package containing a spare distributor, MSD box, and coil on long trips. Doesn't take up much room and it's good insurance. I check the spare dist for corrosion once in a while. I think the most important part of that package is the spare distributor.

As has been mentioned, going for ultimate simplicity has it's advantages. For those out there who have had bad MSD experiences, I have had some people recommend a Pertronix distributor to me, with a built in HEI ignition module. One wire to ignition hot, hook up the coil and that's it. They say that the multi spark isn't that beneficial, all you need is the capacitive discharge for higher voltage. I decided to stick with the MSD world.

I have used an HEI distributor for years....2 wires ...tach and power...never gives any problems and revs to 8000 rpm???? why mess with anything else. IMO the simpler the beter....Oh and mine is a Procomp billet dizzy that I bought new on ebay complete for $60-00 odd ... It has achrome molley gear that works with all types of cams...and no I don't sell them!
John