GT Won't start

[saintjamesy89]

Hi everybody, went to start doing stuff with the GT today and it won't start. I put two cans of fresh petrol in her, battery is new (as is all the ignition system apart from coil), it smelt of petrol so must be drawing some through. When I bought her she wouldn't start, and drawing no fuel through was the problem but it spluttered and coughed then which makes me think this time it's electrical.

Only thing I noticed is that the earth strap from the gearbox was attached at the gearbox, but the other end wasn't attached to anything - there was a lead going from the inner wing to the battery negative lead though. So would there be an earthing issue? All it did was turn over, not even a hiccup or splutter. All the interior electrics worked well and bright. I ended up getting really pissed of, 2 and a half hours yielding absolutely nothing... Gave up when it got too dark to see in the engine bay.

What could have changed since october when she was starting on the 2nd revolution of the engine?

[mat_fenwick]

The fact the engine earthing lead isn't attached to the battery will mean the starter motor return current has to find an alternative path - i.e. through control cables, gear linkage, driveshafts etc and then through the lead from inner wing to battery. That might make it slower to turn over if it was cranking more slowly?

Slow cranking might make it more difficult to start, but I wonder if the problem is ignition related. If the ignition module is mounted on the engine (and hence relying on the engine earth) if that is missing it means the voltage across it could be lower. I've known some modules fail to work when they drop below a threshold voltage.

But that's all speculation - can you put a spark plug in a HT lead you've pulled off, and rest it on the cam cover. If that sparks when you crank it, it's less likely to be ignition. Although it could be that it sparks out of the engine, but not under compression...
If it doesn't spark, then it's an ignition problem.

[saintjamesy89]

It cranks over really quickly thanks to a posh new battery It just won't bloody start! Where can I attach this earth cord? Or doesn't it matter. It's the platted metal type about 1 inch wide, will reach the battery tray base from the gearbox (where it's attached) and it's fairly rusty.

By ignition module Mat, do you mean coil? This is mounted on the bulkhead and has 4 loose spade connectors (like dodgy, loose and dirty etc) on the top around the coil-> dizzy cap lead.

I'll try sucking on the fuel line to the pump to see if fuel is coming through, and the spark plug on the cam cover too (didn't do this today as I was worried i'd electrocute myself!). If the spark is ok, and fuel is coming through, what does that leave, fuel pump and carb?

Thanks for the advice Mat, I hate it when car stuff goes wrong and I don't understand what's going on. The facilities don't help either, it is just a tiny garage in a row of 7 in the middle of nowhere, not even any street lights! The lights on my TXD aren't brilliant anyway.

[mat_fenwick]

Have to go out now, but ignition module is not coil, am assuming electronic ignition not points. If coil on bulkhead my theory is unlikely to be the problem as module is usually with coil.

DO NOT touch sparkplug when cranking! Also careful when sucking ( ) so you don't get a mouthful. Any clear pipes you can check? Check for spark first - engine needs air, fuel, spark and compression - if any is missing it won't start.

Earth lead needs to go to battery negative terminal, but if cranking fast it must have found alternative path. Can possibly melt throttle/clutch cables and make them stick!

[saintjamesy89]

I'll sort that earth out then Mat, i'm almost certain it won't reach the negative terminal but will see, then check for the spark. Thanks for your help

[Kitch]

You've got to check for a spark and fuel, it's the first place to look. Get hold of some carb cleaner or similar, or better yet pore some petrol directly into the top of the carb and try again. This eliminates fuel supply. Then pull a spark plug out and test each HT lead on it, including the coil, by cranking it over and holding the plug near the engine to allow the spark to earth. In fairness, plugs do find it easier to spark in atmosphere rather than under compression, but if you've got nothing at all it'll show up straight away.

I'm with Mat, my initial reaction is the ignition module. You could try spraying the coil with WD40 or something to make it colder (can wake a dead coil up temporarily) but it could also be the fuel pump, which is mechanical on those. It's all speculation really though, only you can see the clues and signs.

The earth lead might be causing the amp to receive a weak signal.....get hold of a jump lead and clip one end to the engine, the other to a nut on the strut top or something. That'll replicate what that strap does, though I would expect slow cranking if it wasn't happy due to a poor earth.

[Gary]

If the earth lead you mentioned is a flat & platted then it goes from the gearbox to the bolt that secures the battery clamp.
Another possibility for non start is that the choke flap has stuck closed causing the engine to over-fuel and soak the plugs, may be worth taking off the air pipe on top of the carb and wedging the choke flap open with a peg or something similar and holding the throttle flat to the floor whilst cranking.
You may have to remove and clean the plugs if they too wet.

[saintjamesy89]

Thanks Kitch, for your down to earth wisdom. If I wasn't busy being cold and irritated I may have followed your logic and tested the stuff that is needed for combustion, but then again, maybe not! I did pour a trickle of petrol into the carb to no change, it was just a trickle so I assumed it wouldn't do anything.

That sounds about right, thanks Gary. Interestingly there is no battery clamp, just a plastic tray on top of the battery plate and a long, oddly angled bolt sticking out the side . I was wondering how the battery was supposed to be secured, there is an overhang (on the wing side) where the base of the battery looks like it'll slot in, so I assume the clamp will act in a similar way.

Would someone please clarify the difference between a coil and ignition module? I know of the former but not the latter. And maybe what the latter does?

[electrokid]

The centre lead on the distributor cap is connected to the coil via a high tension (HT) lead. The coil is the device that changes low voltage into high voltage to produce the spark. The 'ordinary' wiring that is attached to the coil will go to the ignition module. The ignition module produces the right low voltage signal at the right time to cause the spark.

[mat_fenwick]

The module will look something like this:

[B-Hive]

My money is on the module connector plug between the dizzy and the module, if left sit around they can get poor connections. If if started easy before I wouldn't play with the carb nor even suspect the earth strap (especially with a fresh battery)

So I would pull this connector apart (being careful nit to lose the locking wire) and just give both sides of the plug a little clean/scrape with a micro screwdriver.

If its not the connector then I'd then suspect one of the wires on that lead. The MK1 TRS has a similar issue currently but always seems to manage to kick if I jiggle that lead..

Anyway worth a try ...good luck

[Jayboy]

Might be worth pulling the spark plugs out and cleaning them too cos they're likely to be gummed up after so much cranking. Regularly have to do this on the 4x4 cos water got in the fuel when the filler neck rusted away. Always fires up straight away afterwards

Also try disconnecting the supply and return pipes on top of the fuel tank (under a plastic disc beneath the rear seat squab) and placing them in a fresh can of petrol - you'll need to extend the pipe so it will reach the can using some extra piping/sleeving. Even petrol just a few months old is nowhere near as combustible as fresh fuel and can cause starting issues.

[saintjamesy89]

We have no spark, or no detectable spark with cyl 1 HT lead (with attached spark plug) resting on the engine mount. Had to get a passer by to watch while I cranked.

I took off the coil and ignition module and will look at getting replacements, then hopefully i'll have a running GT again!

[saintjamesy89]

Lol, that is the exact same ignition module Mat, your post saounds like you just plucked it from google or something. What are the chances!

[mat_fenwick]

It was a general Google search, but I picked one that rang vague bells from years working on various 205s, in the hope that it would be the same. It's shared over lots of cars. I know you like shiny new bits, but the problem may be with wiring rather than the components...good luck! Worst case is you'll have spares.