Beware of "cheap" electronic ignition modules

[HappyJack]

I’m at the very end of finishing up the center mount Weber Carb install on Emma and have been driving around town to “road test” her prior to taking a long trip to the beach.

Yesterday on the way home from the store, Emma started to hesitate and run ragged.  Bt as I got closer to my house, everything seemed to smooth out and I thought all was well.  That evening I went to start the car and move it out of the garage and it would not start — it would turn over but not even try to catch.  I figured I was having carburetor problems with the new Weber…….!!!  Naturally one tends to jump right on the last thing done to the car as the cause of its problems……..

I  thought there must be something wrong with the fuel flow — but I had plenty of fuel in the lines and carb.  I thought maybe float level in the bowl — still thinking that the new carb was the culprit.

After wasting a lot of time troubleshooting the fuel system, I finally checked the ignition and found no spark — not even a little.  I quit for the night and Royal came over this morning to help, as Ed would say, “sort things out”

Royal, as a good and smart VW-based Tdr owner, had a spare distributor with points installed and preset to the correct gap.  We pulled the distributor out of the car and installed Roy’s spare and Emma started right up.

I think it was Paul who first highlighted the importance of having a spare distributor == and one that had a set of points and cap installed and ready to go.

It turns out that I had pulled the electronic ignition module out of a $79.00 009-type distributor that I purchased last year from CIP1 and put it in a Vacuum advance Bosch distributor I had in the parts box & installed it in the car since the Weber had a vacuum port ready to supply a vac advance-type distributor.

Well that module failed and lucky for me, it finally quit for good while the car was sitting in the garage.

I just ordered a new Pertronix SVDA distributor.  I’ll pull and return Roy’s spare and  install the new Pertronix SVDA.

I also ordered  a set of points and condenser and rotor and cap for the Bosch distributor.  I’ll install those parts, set the points, and put it   in my Pack Up Kit as a spare.

Yes Paul, I learned a lesson and will not disparage those old fashioned points ever again.
And I advise staying away from those bargain basement electronic ignition modules & distributors so equipped.  I paid a little less than $120 for the Pertronix.  I paid around $80 with shipping for the failed unit — definitely not worth the $40.00 savings……..not a good place to economize unless you are looking increase your odds for having to  troubleshoot  a hot engine on the side of the road…

The new distributor will be here Tuesday — just in time for a beach trip Wednesday!!

“Happy there is nothing wrong with our Weber center mount carburetor install” Jack

 

 

[Paul Mossberg]

Glad you sorted it out Jack!

Keeping a spare distributor in the car might be overkill. But I definitely recommend anyone with an “in distributor” electronic ignition module to carry points, condenser and rotor.

Swapping those parts in takes just a few minutes on the side of the road. Set the gap and you’re back on the road. If you have to swap distributors, you might be dealing with timing issues on the side of the road too.

Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica Roadster

If you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)

[edward ericson]

I once needed a coil. Borrowed it from a fellow VW person. And my voltage regulator (in)famously failed on the way out to Pittsburgh a few years back, but the P.O. had thoughtfully stowed a good one under the passenger seat, so no problemo.

[Royal]

It was (or at least it should have been) almost as quick and simple as Jack’s telling of putting my spare distributor in his TDr, and everything being just ducky.  But alas, a few years ago, in our designated Carlisle  hotel parking lot, Schu was having trouble getting spark.  I offered that I had a complete spare distributor, ready to install.  Schu, took my cap and rotor and his TDr fired right up.  He replaced the parts I had loaned him, but I had already installed his old (bad) cap on my spare distributor and stowed it back in its designated spot aboard my MiGi….and the cap that Schu bought for me never made it onto my distributor.

So the distributor that I was carrying in my ready spares bag for the last several years was no good because it had Schu’s bad cap.  I should have known better than put off immediately installing the new cap that Schu bought at the Carlisle show field.  Glad to have discovered it in Jack’s garage rather than on the road away from home.

All’s well that ends well.

 

 

 

• This reply was modified 8 years, 3 months ago by Royal.

[Royal]

Depending on how cock sure, or paranoid, or….whatever you are, you may add to or delete from my list of ready spares always aboard my TDr (I run an electronic Pertronix on MiGI):

Fully ready to be installed distributor with points (set), rotor and cap

Voltage regulator

Condenser

Spare ignition wire

4 spark plugs

20+/- feet of hook up wire and a few wirenuts

a few feet of iron baling wire

fuel filter

duct tape

an assortment of metric bolts and nuts

and, of course – tools including a metric adjustable wrench

and a soft bound edition of “Murphy’s Law”.

 

 

[newkitman]

If I recall correctly, John Muir’s Book has a section  which covers an “A” kit (for local driving) and a “B” kit (for trips.) The “A” kit has fan belt, points, plugs, condenser, rotor, cap, one coil wire,the longest spark plug wire and a couple of spare bulbs all stored in a shoe box. The “B” kit had the “A” kit plus a few other parts (generator, fuel pump, etc.)

Allen Caron
VW based 53MGTD - "MoneyPenny"
"If one thing matters, everything matters" - from the book The Shack

[Toller]

Roy
Have you got a picture of a metric adjustable wrench, living in Canada that adopted the metric system of measurement over 30 years ago, I have yet to source a metric adjustable wrench. Also the farmers in your part of the country must have some pretty tough cattle to be using iron baling wire. Up here they still use sisal or poly string/nets for baling hay or straw. I have a roll of fence bracing wire that I use for fixing split cedar rails, I will have to put some in Sabine in the event I have to make some buckshe repairs.
I picked up a set of SAE/metric sockets and box wrenches in a carry case that is now part of the ballast in the front of the car. I am using Muir’s book and some recent Samba postings to build a kit of tools and parts to add to the ballast

David B Dixon
Port Perry ON CA
Sabine

[Paul Mossberg]

OK, let’s not laugh at carrying bailing wire.

The full story will take too long to tell here. But the short version is: Years ago, my wife (at the time) and I, and a family of four whom we had just met in an airport, ended up in a VW Micro Bus taxi, traveling across Mexico from Guadalajara to Manzanillo. Trust me, there are no highways!

Mid-way through the trip, the engine drops to idle. Driver and I get out, open up the engine cover. Broken throttle cable, luckily right near the carb. Driver walks out into a field where workers were bailing hay by hand. Comes back with a foot of bailing wire.

We used the bracket and set screw normally used at the carb linkage, to attach the bailing wire to the end of the throttle cable. Then simply tied the bailing wire to the carb linkage.

On our way in less than five minutes.

Paul Mossberg
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica Roadster

If you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)

[edward ericson]

I like to call it “mechanic’s wire.”

[HappyJack]

Finally got the Pertronix Single Vacuum, Dual Advance (SVDA) distributor installed, adjusted, and the timing set to 34 degrees Before Top Dead Center with the vacuum hose disconnected from the side of the distributor and the hose plugged.

But before I could get out of the garage for a test drive, I started to over-think the setup and questioned where the vacuum was being supplied on this current Weber Center Mount carburator.  There are 3 potential sources of Vacuum from the Weber carb — 1 labeled Vac Advance and 2 just labeled “vacuum” on the parts breakdown for the Weber IDF 40 carb.

So I called Royal up, he came over with his vacuum gauge and sure enough, the port marked “vacuum advance” did not work as expected.  It produced 0 vacuum at idle.  All the other setups we had seen had around 15″ hg vacuum at idle.

So I popped the set screws out of the two ports that were labeled “vacuum” and hooked those up to the distributor.

Car ran ok but not great and had a hesitation off of idle….classic Bosch 009 distributor behavior that the Pertronix SVDA was supposed to fix.

We quit for the day without a plan of attack to fix the problem.  Royal went home and around 4 AM the following morning, emailed me with info he gleened off of an internet search about how the Weber Carb vacuum port works.

As it turns out, the port marked “vacuum advance” is the one to use.  It just works differently than most — it starts at idle at 0″ hg vacuum and then eases up as you accelerate.  This is done specifically to cure the off-idle hesitation with after market carburetors  and distributors.

I hooked it up as recommended, buttoned up the back end and went for a test drive…runs great with no off-idle hesitation.

…Lesson learned — don’t try to over think the situation and don’t think that everything you read on line is accurate.  Unfortunately, as the old saying goes, “opinions are like assholes — everyone has one but most are full of …” most of what I read conradicted most of what I read…….until Royal found the one post that explained in great detail how the Weber butterfly plate blocks off the vacuum port hole at idle, but as soon as you come off of idle, it allows vacuum to be applied to the distributor, changing the timing and thus getting rid of the “infamous 009 dead spot.”

So now that I’m actually using the correct vacuum port, the car runs great, the electronic points replacement module seems to be doing its job admirably, and all is right again in Emma’s world.

This ends (I sure hope) the saga of the cheap electronic ignition module — and sheds some light on the importance of using the correct source of vacuum (your carburetor, your intake manifold etc.) for your SVDA distributor.

Happy Jack

 

 

[edward ericson]

Glad that worked out, Jack. And thanks for the good info. I’m sure you’re not the only one who overthinks things to the point of screwing them up!

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