Garage Recommendations - 70 Won’t Start

[Fox]

Can anyone recommend a decent garage in the West London/Middlesex/Surrey areas ?

My 70 won’t start and I’m running out of ideas

Last weekend I started as normal and got it out of the garage and shut it off and it wouldn’t start again , I rolled it back in the garage and left it for a week as I thought it may be flooded but today it’s still not starting , checked fuel and it has fuel , pulled a few plugs and they don’t look too bad , checked the spark and there is a spark but it looks a bit weak to me , I tested a brand new lead I have and still a weak spark, distributor cap all looks ok

Called the RAC out today and he was 90% sure it’s the coil , I have MSD electronic ignition

So I went and got a new coil (Blaster 2) and still nothing

Anything else I can check ?

Could it be the MSD box itself ? Not sure how to check the function of that though and would rather know for sure before spending £400 on a new one which is why I might just get a specialist garage to look at it

Thanks for any help

[stevec2004]

Hi Justin,have you tried putting the old fashioned points and condenser set up back in to see what happens?

[Fox]

Thanks Steve , not yet mate , going to check a few more things today first and go from there

[moozmoozmooz]

What MSD unit do you have, I have run a msd and associate them with spark amplifiers in my application it was triggered by standard points. I am in the process of returning my under hood to stock standard and the unit at the moment sits on the bench, I have the instruction /install manual filed somewhere and can dig this out, I seem to remember there being a trouble shooting section.
Out of interest my unit gave a bright blue spark (quite incredible really could double my spark gap)

Best wishes

[Scaf]

I had the “pick” up dial on my MSD which was the cause of my poor starting

[rider]

Easiest way to check a coil is to measure the resistance and see if its still in spec. If its a blaster coil that would be around 1.5k ohms if its an original fit spec that'd be around 3k ohms. Then the next check is the feed voltage into the top of the coil with ignition on and the earthing integrity. Don't leave the ignition on for longer than necessary to do a measurement, more than 15 seconds, as you can fry the electronic module if you do.

[ALLAN R]

I went through some pain like this a couple of years ago. I had the Mallory Hyfire module. Everything would be ok and then suddenly the car would just not start. Then after some fiddling it would work fine for a couple of weeks and then the same thing. I was triggering mine with a Pertronix Unit so I had no idea really what to blame. In the end I stripped out the Mallory module and just used the Pertronix unit and it has been fine ever since. I now have a spare Pertonix unit so its just one screw in the dizzy and two connectors to swap it if there is an issue. This said the Pertonix unit is getting on 10 years old now and no issues with it. When I stripped the Mallory unit there was some slight burning on the board and corrosion. So much for weather protection. In my opinion these modules are of no real advantage on a street engine, just extra complication really.

In my long motoring history I've only had one coil fail and that failed when it was hot and intermittently so the engine would run for a while and then stop. Putting my hand on the coil showed it was red hot. A weak spark could be anything. It could be dodgy wiring on these older cars. it could be the MSD unit. It could be tracking in the dizzy cap. It could be the coil HT lead. If it was one of the plug leads the engine would run easily on 7 cylinders. If you are using points to trigger the MSD it could be dodgy points, the condenser or as said a grounding issue in the dizzy. Make sure the lead grounding the dizzy plates is in good order. If you have a Pertronix unit, looking on the net, these usually fail completely, so no spark at all.