MSD 6-AL spark test - scary results !

[Julian West]

Dear All,

Can anyone help please? I'm experiencing ignition problems, I'm running a 302 with an old style MSD 6-AL pn 6420, an MSD Blaster coil pn 8202, and an MSD Pro-Billet distributor pn 8479.

I check for a spark as per the MSD manual, ie remove the plug lead, unplug the green/violet distributor lead & short with a jumper lead.

I'm getting a spark alright, but it's more like a welding arc! & continues to arc even after I've removed the jumper wire!

Any suggestions?

Thanks in advance,
Julian

 

[Randy V]

I suggest you call MSD Support and get that spark box looked at. (915) 855-7123

 

[Randy V]

There’s nothing wrong with the coil and the distributor is just a simple hall effect sensor (no amplifier), so presumably nothing wrong there.

 

[Julian West]

Thanks Randy,

I think you are right, the 6-AL could well be the problem.

The coil, leads plugs, rotor arm & distributor cap are all new. The inside of the distributor was corroded somewhat & this has been properly cleaned & serviced.

I forgot to add, the rev counter is going haywire, even when the engine is not running.

I will take your advice & call MSD later.

Appreciate your help,

kind regards
Julian

 

[JP Verweij]

Those MSD Blaster coils are a real missery. You better replace that with a Bosch blue coil.
Had lots of failures with the Blaster coils.

 

[Fred/Belgium]

Hi JP,

Do you know an address in EU where I can order ?

Grtz
Fred

 

[Julian West]

Those MSD Blaster coils are a real missery. You better replace that with a Bosch blue coil.
Had lots of failures with the Blaster coils.

I have heard of other failures but I should add my MSD ignition system has run faultlessly since I installed it 16 years ago, I've driven numerous track days, sprints etc.

Sorry if you've had a bad experience with MSD, I guess QC isn't what it used to be.

 

[Davidmgbv8]

If it is not a coil failure then it is probably a broken diode that when cold has contact but as it heats up it expands and breaks the contact. Had an old crane unit do that and it made me crazy because after the car cooled down it fired right back up.

 

[JP Verweij]

Hi JP,

Do you know an address in EU where I can order ?

Grtz
Fred

Bobine 0 221 119 027 Bosch voor o.a. ALFA ROMEO, ASTON MARTIN, AUDI, AUSTIN, AUTOBIANCHI, BMW, CITROEN, DACIA, DAF, FIAT, FSO, INNOCENTI, LADA, LANCIA, MERCEDES-BENZ, MG, MITSUBISHI, MORGAN, MORRIS, NISSAN, NSU, PEUGEOT, PORSCHE, RENAULT, SAAB, SEAT, SKODA, STEYR, TALBOT, TOYOTA, TRABANT, VOLKSWAGEN, VOLVO, WARTBURG | Winparts.be - Bobine

Zie ook de whatsapp die ik je gestuurd heb.

 

[Fred/Belgium]

Tx
Ordered

 

[Julian West]

If it is not a coil failure then it is probably a broken diode that when cold has contact but as it heats up it expands and breaks the contact. Had an old crane unit do that and it made me crazy because after the car cooled down it fired right back up.

Thanks David,

very interesting. Looks like the 6-al will need replacing or repair.

 

[Liam39]

I had an issue with a faulty hall effect sensor in the distributor. The rpm reading randomly cut to 0 when driving, worsened by heat. Not saying this is your issue, just adding that the hall effect sensors can fail, although MSD cdi boxes are known to be unreliable.

 

[JP Verweij]

... although MSD cdi boxes are known to be unreliable...

I never ever had issues with MSD 6A & 6AL & 6 BTM boxes. Have 4 cars running them for 20+ years. Points triggered, MSD Pro Billet triggered and Ford Duraspark triggered.
GT40 is running a used one sourced on ebay.

Blaster coils are unreliable, just google it.

Otherwise, that little red clowns box as we call it overhere in the Netherlands does what it advertises.

 

[Randy V]

I’ve had very good experiences with the MSD Blaster coils, but I have taken care to mount them in an upright orientation as all oil filled coils should be mounted. Epoxy filled coils can be mounted in any position.
Here’s a blurb from MSD on them and a photo of one of my many installs (my street rod)..
“The Blaster Coil is designed to mount in most factory canister coil mounts. MSD also offers a Chrome Coil Bracket, PN 8213. It is recommended to mount the PN 8202, PN 82023, and 8223 coils in an upright position. The High Vibration Coil, PN 8222, can be mounted in any position due to its epoxy potting compound.”

 

[Julian West]

Thanks all for your input.

After a call with MSD tech, it was established my long serving 6-AL had failed. A replacement digital 6-AL has resolved the problem.

Kind regards
Julian

 

[Liam39]

In my last 289, I wired the 6AL with a Deutsch connector so I could bypass it in seconds for when it fails. This is how little faith I have in MSD CDI boxes.
When I was much younger, I lost a national title because of a MSD. Once bitten, twice shy.

 

[Brian]

I did the same with my Cobra so megasquirt's internal BIP373 could directly fire the coil. I haven't had to use it yet. All I have to do is unplug the MSD from the loom and plug in the bypass plug that's zip tied to it.

 

[Howard Jones]

Julian, When the same thing happened to me several years ago I sent the bad one in for repair. It has served as my backup for many years now and as per Murphy's rule, "once you have a spare on hand you will never need it" The other two in my GT40 and SLC have worked fine ever since....................knock wood!

If I remember correctly getting it fixed was less than 1/2 the cost of a new one, Something to think about.

 

[Ron Earp]

That thing will light your ass up! Might shoulda kept it around for entertainment purposes!

 

[Julian West]

Thank you all for your input & suggestions. My new digital 6AL is installed & fully operational. I would have liked to send the old unit back to MSD for repair but shipping costs & import duties add a lot to the repair costs so it was cheaper to source a new unit here in the UK.

The digital version offers some improvements, including a single block connector which makes it much easier to disconnect when working on the cars electrics. Also the rev limit can be indicated on the rev counter, which is a nice touch.

Kind regards
Julian