Technical Cruising and 50 MPH and car suddenly cuts out.

[Sbf500]

Morning all.

So out for a trip to the local hardware shop and on my way home cruising along in 4th gear at aprox 50 MPH the car suddenly cuts out. Had the feel of HT leads falling on the exhaust so I was very supprised to open the bonnet to find them sat happily in place in there holders.

So first thought was ignition, had a spark at both plugs, not sure if it was a strong as could be but nice and blue. Checked the king lead for good measure andt his has a very strong clear blue spark.

Next checked for fuel, pump was working fine, emptyed the float chamber by removing the main jet and then checked it would re fill it which it did.

So now i am scratching my head and it is starting to get dark so out came the AA. We checked everything again, changed the condensor for a new one, swapped out the rotor arm, swapped the coil and swapped the plugs. Still nothing, unforfuately I didn't have a spare distributor cap or HT leads with me or at home but I was still getting a spark at the plugs.

Even with easy start it wouldn't fire. So then I wondered if the timing has somehow gone wildly out, nope checked static timing and it was fine, or at least enough to start and drive home, even took the rocker off to ensure it was happening before any valves were opening. Checked valve gap while there as well.

It was so sudden the breakdown and the fact that not even easy start would get it to fire I suspect ignition but the fact I have a spark is really stumping me. I have a new cap and HT leads on there way but wondering if anyone else has experienced anything similar which they can point too. It just wont fire at all, cranks and cranks and cranks.

Thanks

 

[Goldnrust]

Firstly, I’m sorry to hear of the brake down!

Secondly, it sounds like you’ve covered all the basics!

You’ve got spark and you’ve got fuel, one thing you haven’t mentioned checking is compression, might be worth a quick check, even if it’s just a thumb over the plug hole type approach to check both cylinders are equally sucking and blowing.

Also, double check you’ve not swapped plug leads over during the ignition checks. If the problem was ignition, and you’ve fixed it with the new parts mentioned above, but somehow mixed the leads up then the spark would be 180 degrees out at the cylinder but would read fine on the static timing check at the crank.

 

[Sbf500]

Firstly, I’m sorry to hear of the brake down!

Secondly, it sounds like you’ve covered all the basics!

You’ve got spark and you’ve got fuel, one thing you haven’t mentioned checking is compression, might be worth a quick check, even if it’s just a thumb over the plug hole type approach to check both cylinders are equally sucking and blowing.

Also, double check you’ve not swapped plug leads over during the ignition checks. If the problem was ignition, and you’ve fixed it with the new parts mentioned above, but somehow mixed the leads up then the spark would be 180 degrees out at the cylinder but would read fine on the static timing check at the crank.

Yes that did happen, and I left the king lead off at one point. I got very excited thinking it would then be all fixed but no. Compression test is definitely on the list of things to check although turning over by hand there is definitely compression on both cylinders so I’m not hopeful.

 

[Elliott 4]

Morning all.

So out for a trip to the local hardware shop and on my way home cruising along in 4th gear at aprox 50 MPH the car suddenly cuts out. Had the feel of HT leads falling on the exhaust so I was very supprised to open the bonnet to find them sat happily in place in there holders.

So first thought was ignition, had a spark at both plugs, not sure if it was a strong as could be but nice and blue. Checked the king lead for good measure andt his has a very strong clear blue spark.

Next checked for fuel, pump was working fine, emptyed the float chamber by removing the main jet and then checked it would re fill it which it did.

So now i am scratching my head and it is starting to get dark so out came the AA. We checked everything again, changed the condensor for a new one, swapped out the rotor arm, swapped the coil and swapped the plugs. Still nothing, unforfuately I didn't have a spare distributor cap or HT leads with me or at home but I was still getting a spark at the plugs.

Even with easy start it wouldn't fire. So then I wondered if the timing has somehow gone wildly out, nope checked static timing and it was fine, or at least enough to start and drive home, even took the rocker off to ensure it was happening before any valves were opening. Checked valve gap while there as well.

It was so sudden the breakdown and the fact that not even easy start would get it to fire I suspect ignition but the fact I have a spark is really stumping me. I have a new cap and HT leads on there way but wondering if anyone else has experienced anything similar which they can point too. It just wont fire at all, cranks and cranks and cranks.

Thanks

Hi, yes. I can be driving along at 50 and my car completely cuts out. Has yours stored any fault codes in its memory? I’ve had two new coil packs and leads fitted. Mines a fiat panda. What’s yours? Please see my thread.

 

[Sbf500]

Hi, yes. I can be driving along at 50 and my car completely cuts out. Has yours stored any fault codes in its memory? I’ve had two new coil packs and leads fitted. Mines a fiat panda. What’s yours? Please see my thread.

Thanks Elliott. Unfortunately at 51 years old little Muso being a classic 500 is about as technical as a type writer, sometimes it would make life a lot easier if he could tell me what was wrong but as he can’t it is the old process of elimination I think.

 

[Elliott 4]

Oh crikey - I didn’t realise you had an old model. Mind you my fault codes haven’t really helped much as we are still in the dark.

 

[Elliott 4]

Oh crikey - I didn’t realise you had an old model. Mind you my fault codes haven’t really helped much as we are still in the dark.

If we get to the bottom of it I’ll let you know, just in case it’s the same thing causing yours to cut out.

 

[Ant Knox]

I've had similar when running at higher speeds after being sat in hot conditions or having just been run (so effectively a hot start) it would seem to have been a vapour lock. After a bit of a cool down, it ran fine, and has ever since. Could also be the coil pack breaking down in the heat.

 

[Elliott 4]

That’s brilliant that yours has since run ok. It’s had two new coil packs.

 

[Sbf500]

Right so an update, it’s not fuel related, pump is working fine, put on my spare carb and cleaned out the one on the car and not a thing with either. Replaced all the ignition with either new or known working spares and still nothing. Did a compression test and all fine.

It has a spark, it has fuel, it’s not heat related as it has been sat cold for a couple of days. Could the timing some how have gone out of whack. The static timing is as per the book which is pretty much bang on and only needs a slight tweak when using a timing gun but all I can think of is that the spark is not hitting the cylinders at the right time. I’ve checked and rechecked the leads are on the correct cylinders.

Could the timing chain have jumped a tooth? Surely that would have made a horrible sound and deposited bits of metal in my sump. I really am clutching at straws now.

 

[Sbf500]

So turns out I had no idea what a good spark looked like. What I was seeing while swapping parts was a week imitation of a spark. Basically my expensive swiftune condenser had bitten the dust with less than 2000 miles on it. Not happy for £30. Also my spare was duff. Popped in a new spare today and nearly blinded myself (slight over exaggeration) with the power of the spark. After that car fires straight up.

I think from now on I am just going to stick to the £5 mid range Bosch ones and just treat them as a consumable and carry a few at all times as they are quick to swap.

 

[fiat500]

So turns out I had no idea what a good spark looked like. What I was seeing while swapping parts was a week imitation of a spark. Basically my expensive swiftune condenser had bitten the dust with lads that 2000 miles on it. Not happy for £30. Also my spare was duff. Popped in a new spare today and nearly blinded myself (slight over exaggeration) with the power of the spark. After that car fires straight up.

I think from now on I am just going to stick to the £5 mid range Bosch ones and just treat them as a consumable and carry a few at all times as they are quick to swap.

That's what I do, although I'm not sure that they are always genuine Bosch despite having believable packaging; the same applies to "Marelli" ignition parts. My current condenser has done 7.000 miles with no issues.

 

[Goldnrust]

Glad to hear you’re sorted, and that it was an easy fix in the end.

…and we’ve all been there. A few years back I didn’t spot a weak spark on my motorbike and chased various issues before a fresh condensed showed me what a real spark looked like.

 

[lazylobster]

So turns out I had no idea what a good spark looked like. What I was seeing while swapping parts was a week imitation of a spark. Basically my expensive swiftune condenser had bitten the dust with less than 2000 miles on it. Not happy for £30. Also my spare was duff. Popped in a new spare today and nearly blinded myself (slight over exaggeration) with the power of the spark. After that car fires straight up.

I think from now on I am just going to stick to the £5 mid range Bosch ones and just treat them as a consumable and carry a few at all times as they are quick to swap.

I would have a word with Swifttune as this is not good and there may be a faulty batch.

 

[the hobbler]

I would have a word with Swifttune as this is not good and there may be a faulty batch.

I completely agree with Lazy Lobster---I have never known this sort of problem with the Swiftune Condenser--show them your invoice number and ask them to comment.

 

[Sbf500]

Annoyingly I can’t find my order email or receipt. Anyway, from getting the multi on it I get zero resistance so it isn’t charging up which is then confirmed when I switch to volts as I then get zero volts and no discharge. So it looks like a complete short. I’ll take the wires off and see if they are the offending part or if it is internal.

It explains the very sudden way in which the engine just stopped. Anyway tested all my other condenser and have two spares in the car now so hopefully that won’t stop me for long again.

Would it be as fun if there wasn’t an element of risk in not making it home?