TSD

Nige, Don't describe the old modded ECU as 'state of the art'... I've got coffee all over the monitor now

It depends how the coil is wound. The coils could be wound in the same direction or in opposite direction on the former. I imagine they are wound in the same direction, and the system is operating almost the same as an isolated transformer. The current through the ground terminal is due only to the imbalance between the 'used' and 'wasted' spark voltages. If you insulate one side, the other plug still fires, using the centre tap as ground return. It is a little less efficient than an isolated coil, because you cannot use the fact that the 'wasted' spark is established at a lower voltage to gain voltage on the 'used' spark side. (If they were wound in opposite directions, then it would effectively be two small coils firing together in the same polarity. Also radiated and conducted electrical noise woul be increased, which is bad for type approval testing and for all the complex electronics they keep filling cars with.) That's because a misfiring plug is still sparking, just not near any combustible mixture, so the other plug can still fire. An o/c lead breaks the circuit , and no plug can fire, unless the insulation breaks down. The insulation on gen. parts EDIS leads is very good IME. Dave

From a mail shot received this week... For a limited period, Alibre is offering the standard version of their 3D cad software for $99 / £99. Alibre The UK distributor is Mintronics I've used their limited free version in the past, and I thought the paid version looked decent value at £800, so it looks a proper bargain for £99. It's not SolidWorks, but if it was, it would be priced accordingly. (No connection, or commercial interest.) Dave

The voltage rating (which I've never seen specc'ed, but never looked either) is irrelevant unless you already have a misfire. The voltage at the plug rises until the spark ignites, then no further, in fact it drops to a sustaining voltage, that required to maintain the arc through the now ionised gas path.

I recall two brothers (who may hang around this forum now and again) who had a very convincing looking chequer plate floor in the dunny

You're not helping...

I can see the time coming where I ask myself each morning "Which Ibex shall I take to work today?"

I *think* that I disagree with BBC on the theory, but in practice he's correct. You need to complete the circuit for current to flow, so if you disconnect one end of the coil, you drop two cylinders. But in practice it's very hard to disconnect the coil, all that happens is that it arcs out from the end of the coil to vehicle earth, which can happen externally from the end of the coil body, or internally through the insulation. EDIS has a large margin of spare energy (as evident in the photo Fridge posted), and it's much easier to strike an arc in air at atmospheric pressure than it is in a fuel rich mixture under pressure, so a long spark is quite easy to acheive. When the coil is fired, the terminal voltage continues to rise, until the arc is established (or internal losses use up the available coil energy) Once the arc is ignited, it takes much less voltage to sustain the current path through the ionised air track, so overall spark duration may not change by much, especially as EDIS will ensure the coil is fully charged by extending the coil charge time before the next spark. The coil may arc over internally without apparent damage, either because the manufacturer incorporates a 'failsafe' spark gap into the coil design, which ignites at a voltage much higher than needed to light off the plugs, or by simply punching through the insulation. This isn't usually too much of a problem as the oxide residue created by burning the insulation is also an insulator, but I suspect it makes the coil more likely to break down at reduced voltage - and so become a 'weak' coil. (I don't know if there is a failsafe gap included, but I would if I were designing it, and it's easy to imagine it could be done at zero cost). Dave

I'm obviously missing something, explain?

One of three things happens :- 1) Nothing 2) The disconnected end arcs out from the end of the coil, and you get a very weak spark on the connected cylinder. 3) The coil arcs out through the internal insulation, and the coil never works properly again, due to reduced breakdown voltage The coil drivers don't really want to be switching a fully charged coil either, so ecu/edis damage is possible (though probably not likely).

Not different banks, different cylinders running reversed polarity. EDIS is a wasted spark system, using four double ended coils. Two cylinder spark at a time, one on compression, the other on exhaust stroke. The same charge of electricity discharges through both spark plugs, but in opposite directions. The current path is from one end of the coil, from tip of one plug to the body, then through the engine block and the body of the second plug, to the tip and returning to the coil. Because the erosion of the plug is affected by spark polarity (like welding with reverse polarity) the effect is different on 'normal' polarity plugs to the reverse polarity ones.

Over wetting the plugs with fuel can cause them to fail, causeing misfire. I can only guess at the mechanism that causes it, but I saw it several times when messing with the first MS units. When I was working with the prototype EDIS code, I never had any plug failures I could relate to that. Every time I've seen your truck, starting hasn't seemed to be its strong suit, so that might well be part of the problem. The hot spark does tend to increase the erosion of the plug though, and remember that half the plugs are firing reverse polarity, which changes the erosion / metal migration pattern. Ford USA used to spec single platinum plugs for the cylinders firing 'normal' polarity, and double platinum plugs for those running reversed. Maybe worth the price of one set of double platinum plugs to see how long they last? Dave

"Your tax dollar at work" It's a few years since I did this, so my memory may be wrong on exact detail, and there may be better stuff available now. At the time I was looking for a good quality plug to fit a standard in-car cigarette lighter socket. I was looking worldwide, and I bought and tested to destruction every likely candidate I found. I never found a plug that was capable of a reliable 15A. (By reliable, I mean a continuous 15A for many hours without problems). The sockets usually have a decent amount of metal, and using fat wiring helps conduct heat away, in short they aren't usually the problem. The plugs normally have a spring in them which doesn't conduct heat well, and looses it's temper when it heats up, making the problem worse. Good quality plugs will have a flexy copper braid up the middle of the spring, or some other method of preventing the current travelling through the spring. If there is an inline fuse, that will get pretty hot running near it's rated current, and that can destroy the spring and/or melt the plastic body. The plugs with the removeable red cap (converts them to a DIN style plug, if you didn't know) all appear to be a copy of the Hella design, and most share the same design flaw. They are usually a fraction too long, so when you plug them in to a 'real' cigarette lighter, they have a tendency to pop out on every bump. Filing off the tip a bit lets them seat on the spring which holds the ciggy lighter before it pops out. Obviously this doesn't apply if you use the accessory sockets, rather than a cig lighter socket. Farnell sells a '15A' copy of the Hella plug which has a solid centre pin where the fuseholder normally is. They heat up less, having no fuse. Marinco makes a decent plug and socket combo (each half is compatible with 'normal' versions, but offers a splash seal and a twist lock when used together.) Either of those is reliable at 8A, maybe more if you use fat wire and are lucky.

I don't have any pics of this panel installed, but this is the CNC panel I had made for the Ibex.

The hose connector on the cooler is Tee'd into the fat riser pipe into the bottom of the expansion tank. The oil cooler connections on the rad are blanked off.

Don't you mean Brickiln

On my rover diffs, the ARBs had 3/16" tube, and the fitting on the diff housing had an internal 3/8-24 parallel thread. The only source I could find in the UK was as ARB spares, but they were easy to source in the US.

<geek> Bosch claim the maximum efficiency of a typical aircooled alternator is around 65%. Mean efficency in normal use is typically 55%. For a given current load, a larger alternator (ie higher power capability) will usually be more efficient than a smaller one. It will be electrically more efficient, but that is offset a little by the increased rotational mass requiring increased energy during acceleration. Copper losses in the field coils and diodes are constant wrt to rotational speed, but mechanical losses, stator copper losses and Iron losses are roughly proportional to rotational speed. </geek>

Why not generate a PWM output, either using the onboard timers, or simply decrement a counter in the main program loop (if the loop has fairly stable timing) or via an interrupt routine. Feed the output via an integrator to the LM3914 (bargraph driver that FF used). That only uses one pin from the micro.

From the International WSM Crank main bearing journals 63.471-63.491mm ( 300tdi = 63.475 - 63.487 ) Crankpin diameter 58.725-58.745mm ( 300tdi = 58.725 - 58.744 ) Google 'service_manual_hs28l.pdf' for a download. Note this isn't exactly a bootleg - the manual was a free download from International when the engine was in production, as was the parts catalogue.

As others have said, I think you are entitled to repair or replace to the pre-accident condition. The insurance company will want to reduce their costs as far as possible but they must use a competent assessor and repairer, and with JFs opinion available to you, they'll have a struggle to get anything past you that you don't agree with. I'm going to keep your photos handy for the next time I consider not having the Ibex as my daily driver (which isn't often!). JF had a demonstrator 250HT for sale a while back - if it's still for sale, and acceptable to you, the ins. co. may go for that if you suggest it, given the time delay in building a new truck and the ongoing costs of providing you with alternative transport? Glad you are OK (at least compared to the alternatives!) Dave 5F041

IIRC the filter is slightly compressed by the brass nut when fitted, so they always look a little bit squashed. Good luck!

I notice you have the mechanical fuel pump... is it possible that there is sediment collected in the pump body? Do you have a decent filter before the pump? Have you checked it recently? Have you checked for water in the fuel? Why do you say it's defo not icing? Have you checked the floats aren't sticking in the carb? Do the easi-start thing. The vacuum bulb on the dizzy is open to the atmosphere on the Essex. I had some very odd symptoms once when some mud got in there - the timing got shifted randomly as the mud jammed the diaphragm in different positions. You won't have mud, but you could have sticking timing? Dave

Where do you think it's above 0C ?

I agree with you Steve, but I wouldn't try squirting petrol into a hot Essex lump, they can be a real pig to start when warm if the fueling isn't just right, and lead to a wrong conclusion. Easistart will do the job just lovely though!