XFlow randomly stops running, why and how to fix?

[TexasDreamer]

1991 XFlow twice over the last 4 months has stopped running for no apparent reason. The first time I was decelerating on a frontage road about to turn off and it just quit. No hiccup, no sputter. Needles on the gauges went to zero and the engine stopped running. I coasted to a stop in a safe place, thought about it for a minute, then turned the key and it started right up. Yesterday I was making a left turn through an intersection at low speed and it just quit again. I didn’t notice the gauges. I started it up while still coasting and it ran fine all the way home. At twice in four months it’s very intermittent so it will be hard to know if I’ve really fixed it. Any idea on what’s wrong and how to fix it?

[Jonathan Kay]

Any work done or changes made before this happened?

What sort of ignition system does it have?

It sounds as if you're losing electrical supply to the ignition system and the gauges. So check connections at the battery and the battery and engine earths and have a look at the ignition switch and its connections. Wiggle each while the engine is running and see if you can reproduce the problem. If you can't then inspect, wiggle, disconnect, clean, reconnect. 

Have you got a multimeter and would you like the wiring diagrams?

Jonathan

[ECR]

1990 cross flow and I had intermittent misfires over quite a long period. Eventually it dumped me by the roadside in France. I eventually discovered that the Faston connectors to the back of the alternator had oxidised and that was the cause. Apparently the wiring to the rear of the alternator is part of the ignition feed. Worth a look and easy to fix just clean them up

[Sooty]

Sounds like alternator issue, how tight are the connectors on the back of the alternator. They do suffer from heat damage from the No1 primary and the wiring goes hard and brittle as a result.

[Jonathan Kay]

Inspecting the connectors and wiring at the alternator is always a good idea. But I wouldn't expect a fault there to take out all of the instruments... 

Jonathan

[revilla]

... and I wouldn't expect it to start again after a minute. The one thing you fiddled with in the meantime was the ignition switch. I'd stay there.

[barry watts]

Good suggestions already, but I would also go through the fuses and clean all the contacts. Also my crossflow would start fine but not the next time after switching off.  That turned out to be the master switch.

Good luck.

[OldAndrewE]

My thoughts would be the ignition switch as well.  Obviously the battery is fine as it is turning over and starting after the "event" so there should be power but it sounds like it is behaving as if it has just been turned off. Burnt/corroded contacts in the switch?

[SM25T]

Any chance your knee touched the key ? Doesn't take much to stop it dead, which is rather disconcerting.

[TexasDreamer]

I had a quick look at the ignition switch. The contacts look slightly corroded. I'll clean them up first thing when I have more than a few minutes. I did find a purple/Yellow disconnected wire near the fuse box. Wonder where it is supposed to be connected? I'm not sure on the ignition question. There is a silver box under the dash which says Lucas electronic ignition amplifier. 

[TexasDreamer]

[Jonathan Kay]

[Jonathan Kay]

"I did find a purple/Yellow disconnected wire near the fuse box. Wonder where it is supposed to be connected?"

Purple/Yellow is often "Horn to horn relay".

Do you know if the horn is original, and does it work?

Jonathan

[Jonathan Kay]

"I had a quick look at the ignition switch. The contacts look slightly corroded. I'll clean them up first thing when I have more than a few minutes."

Before doing that start the engine and wiggle those wires and the key in the switch and see if it cuts out. (The fault is so intermittent that it's going to be hard to know if any intervention has made a difference.)

Jonathan

[Tazio]

I have a spare ignition amp if its any help.

Alan

[Wrightpayne]

I had an ignition switch fail - I got a replacement switch from Rimmer Bros in the UK for a Landrover Defender that fitted into my original lock barrel.

I took the switch apart. Inside is a set of contacts (that the wires connect to) and a copper shoe with various holes and slots. When you turn the key the copper shoe bridges the contacts applying power to each as the key is turned. Behind the shoe plate is 3 or 4 little springs that apply even pressure to make a good connection - one of my springs had broken.

Mine just cut out completely and wouldn't even spin the starter. It was at a track day and someone spotted the red ignition light flicker when turning the key which helped narrow down the fault cause.

Ian

[AnkerB-S]

The Lucas Electronic Ignition Amplifier is a companion to the Lucas distributor with optical "points". Many Z-flow owners have replaced the Lucas system. I replaced mine with a Burton Power one with an Aldon Ignitor inside.  Much simpler and supposedly more reliable.

[Roger King]

Absolutely anything is more reliable than that particular Lucas item, but seeing as the gauges failed as well it sounds far more like a power supply issue.

[TexasDreamer]

Wiggling the key didn't cause the failure. Pawing all around under the dash didn't' cause it either. All the lights, horn etc. work as expected so no matter how messy the wiring is, it's functional and I'm not inclined to spend time figuring out what was done and why. So far, I have cleaned up a lot of electrical connections. Before I worked on them, I wiggled and pulled to see if engine stopped. No luck so it's hard to know if this will fix it or not. Cleaned up the Alternator connections, the ground connections as directed in the Owners Manual, the fuses, the ignition switch. I'm going to let it ride and see what happens. Thanks for all the advice :)

[Jonathan Kay]

Thanks for the update.

Hope it doesn't recur. But if it does I'd take the opportunity to immediately play with the connections of interest and see if the gauges come back to life.

Jonathan