1. Ignition Problems

So, first start of the van today. Wired her up and turned her over, starter motor kicks in and engine not firing up. All the work, the blood, sweat and tears of the last 10 months and nothing. There goes the night of glory I had planned. So what next, the moment I had dreaded – trouble shooting. So having read a little I started with the basic elements needed to get her going:

1. Fuel.
2. Air.
3. Spark.

So, having spent a good day going over the wiring my Type 4 is wired as per the 1976 Bentley diagram with the exception of the diagnostic unit. I am guessing by the fact it had been ripped out it was more trouble than not but happy to be corrected on this. The only slight difference I have is that my fuel pump is an electric in-line pump and was connected direct to terminal 15 on the coil (positive +) – probably a little unsafe, relay ordered. I had replaced the fuel lines and filters and connected them to the carb, so barring carb issues I was happy here. So when key engaged, fuel pump ticks and fuel being pumped out – also happy I have 12V on the coil at turn over, 12V to the pump and more importantly fuel to the carb. Checkpoint 1 – SORTED! Unless Carb shagged???

Next Air, now I know there are no blockages and air filter is new. Easy! Checkpoint 2 – SORTED!

So now the complicated piece – Spark! First things first, is everything connected up as it should be? YES. So, let’s undo a plug and work back. Plug one unscrewed (easiest one to get to with tinware on!) Next earth the cathode to the engine block and turn over. NO SPARK! Now, my HT leads are all new, but the distributor is not, let’s earth the lead going to the central position on the distributor cap and turn over – STILL NO SPARK (this does not discount a faulty distributor cap, it means there is a problem earlier in the circuit somewhere). So, worked back to the condenser or coil – 12V on terminal 15 – CHECK! Continuity (the green lead) between Terminal 1 and the points – CHECK! So, now chin scratching time. Time to check the relationship between the points and TDC on Cylinder 1. Now when I built the engine the TDC mark was all marked on the distributor (and checked several times during the rebuild) so I know my mark is right. At this point in the engine cycle you should have the points open – mine are which is good, right?? So in theory this should induce the 20,000 Volts needed to generate a spark, but it isn’t ??? SHIT BALLS! So this could be one of two things (my opinion as Vehicle Electrician with 9 minutes experience!). The coil is buggered -1. The points are buggered – 2. Cheapest thing to test is the gap clearance in the points – this should be xxxxx. If this is correct the only other component to worry about is the capacitor – if you think this is buggered just buy some new points – they cost £3!!! All of this is OK! Next thing is our only other option – buy a new coil, these are not £3 but £65. Ordered and now retesting..

Thought it might be useful to add a little science section on the how a spark is actually generated, clever lads them old fella’s! Hopefully helps with the fault finding process:

So a condenser or coil is essentially a huge inductor. Imagine two coils wrapped around each other and in turn a magnet. One coil is fed by 12V and has a small amount of coils. 12V flows through this to earth via the points until they open. When they open , this causes a reverse voltage, which in turn creates an Electro Magnetic Field (EMF) which in turn creates a huge voltage in the secondary coil, which has a huge amount of coils (in our case and conveniently 20,000 volts) which is fed in turn to the spark plugs via the distributor cap – SIMPLES!!!

1. Fan Issues – Install & Debug

So here is a quick video I pulled together when I debugged the fan installation for the heating system. Hope it helps?

3. Broken Wheel Hub Stud.

If this happens, like me you’re an idiot! Don’t use a torque wrench on your nuts! Throw away buy another off Dave!