Running like a dream to rough then stopped all in 24 rs.Sorted. it was the Spark Plugs

[mojobaby]

You managed to get it started last Friday with the help of a friend.
If you're 100% sure that your timing is correct, then check the condition of the distributor cap. Clean up the terminals and make sure that the centre carbon brush isn't stuck in. It's got a spring so when you push it in, it will pop out again.

Take the leads off the spark plugs one by one and hold the tip about 5mm from the engine block while you turn the engine over. you should see a spark.

Clean up your spark plugs with a little wire brush and some fine sand paper.

If you have a spark at the plugs and it still doesn't start, then your timing is still out or you have a fuel supply problem at the spark plug area.
I would imagine that the tip of your plugs should be a bit wet after turning the engine over a few times

 

[Sprackers]

Hi Mojobaby

Wel I have just got back from working on the car and guess what ..................SHE STARTS!!!!!

I recieved the new points this ,morning and the new condenser.

I took the distributor off completely and fitted the points and condenser sitting at home, I then replaced the whole lot and repeated the process.

Flywheel notch in the middle.

Rotor arm pointing townards the Nº1 cable.

Replaced the dizzy head.

Got in the car....nothing.....I had a friend turn the ignition as I twisted the dizzy head. Just didnt fire up. So it wasnt the points or condenser.

So my thinking was check the spark at the spark plug.

Took the spark plug out and BINGO.........

They were filthy and carbon clogged.

With my wire brush cleaned the plug ends and also slid a piece of sandpaper in between the gap and sanded a little both sides.

All the plugs were blackended

replaced all.

Dizzy head back on.

Ligned up Nº1 lead to and of rotor head.

By this time my mate had got bored and gone home so I jumped in the car myself and turned the ignition........BRRRRRRRRRRRRRRRRRRRRRMMMMMMMMMMMMMMMMM

I managed to keep her running whilst I dived under the bonnet and twisted the dizzy and found the perfect position. anti clockwise about 40º from initial postion from 6 O'Clock to 4 O'Clock.

Conclusion:

Clean spark plugs.

I then got back just now and opened up my email and read your email. We would have got there.

I am still puzzled as to why this would occur in the first place and why overnight. ie the evenning before she fired up fine then the next morning she did not start.

Cold temperature?


Thanks for all the advice.




Now for a celerbratery Beer or 6

 

[mojobaby]

Hi Sprackers, well done, your perseverance paid off.
I'm sure that you can now set your timing with your eyes closed

 

[Sprackers]

Exactly hahaha.

I would point out that it would have been a lot quicker

I think as a guide dont follow my (popular)mis-conception as regards setting the timing.

Lets assume that you have CORRECTLY moved the flywheel notch to the middle notch in the bellhousing AND you have as a result the rotor arm pointing towards you when you lean over the engine from the offside (French car)

Lets assume you have done that bit correctly. That bit is not difficult.

From everything I read and was advised I believed that after replacing the dizzy head (rotor arm at where the Nº1 cable is) I thought that unless it is EXACTLY in the correct position the car would not start.

When I say 'correct' I thought that if the dizzy head was 0.05 mm to advanced or retarded of where the spark was, the engine would not start.

As a result I spent hours turning the engine over, then getting out of the car and moving the dizzy head 0.5mm at a time backwards and forwards thinking i was just missing the point of spark.

In fact, its going to fire up if the dizzy head is replaced and Nº 1 cable is 'appoximately' in-line with the rotor arm.

If it doesnt start when the dizzy head is replaced roughly in the right position then its probably not the timing.

 

[mojobaby]

If you follow the correct procedure then it is pretty straight forward. Of course it is possible to have the mark on your flywheel lined up and the rotor facing 180 degrees in the wrong direction. Thats because the flywheel turns around twice for a single rotation of the distributor.

I wonder why your spark plugs were so bad?

I bought my car when I could still get Super petrol. When they stopped selling it, the Renault garage told me to use SP95 unleaded and to get a lead additive which is available also in the supermarkets here.
Before this, someone told me to use SP98,(without a lead additive), which I did and failed my roadworthy because of exhaust smoke. My exhaust was black as were my spark plugs.
When I changed to SP95 and the additive, the smoke disappeared.

 

[Sprackers]

Yup got to make sure rotor is not 180º in wrong direction. Simple after you have done it about 27 times in 2 hours.

Good question as to why spark plugs so black.

I concur with the black smoke and black exhaust.

I will try you suggestion of the addative.

Am I right in thinking that petrol caled 'Super' here in France is leaded? and can I use that?

 

[mojobaby]

No, leaded petrol was phased out in 2002/3. Do NOT use E10 petrol!!

I use SP95 unleaded or "Sans Plomb"

Then put in the lead additive

 

[Tripyrenees]

Me too

 

[benchseat]

All very satisfactory, but one question remains : why did the timing go so far out that the distributor had to be rotated by 40º to restore timing to optimum?

Is the timing chain tensioner broken or badly adjusted so the chain is slack and it slipped a link on the sprockets? This happened to me once.

If it did, this would put the timing right out and possibly contribute to the plugs fouling-up in short order.

 

[Sprackers]

Hmmmmmm. Not sure as this is the first time i've heard about a timing chain.

I have actaully just replaced the dizzy again now and did the same.

rotated the Dizzy so that the Nº1 spark lead is right over where the rotor arm is pointing.

Jumped in car and she started....

Whilst she was running I jumped out of car and rotated the dizzy head slowely anti-clockwise and I could hear her speeding up the ticking over...ie getting to the optimum point.


It was the same amount of twist from 6 O'Clock to 4 O'Clock.

As regards the spark plugs carbonising (Iv'e just made that word up) I took a look at my Haynes manual (page 89)and it showed a photo of exactly what mine looked like.

Underneath the reason was the following

Carbon Fouling:
Dry,black sooty deposits.Will cause weak spark and eventually misfire.
Fault: Over-rich fuel mixture.
Check: Carburettor mixture settings, float level and jet sizes; Choke operation and cleanliness of air filter.

 

[malcolm]

Timing chains are reliable on these things. If they do start going slack on the later engines you are alerted by an annoying bong bong noise at idle. I've only had the trouble on overloaded versions of the engine in a R5.

I don't fully understand the sequence used to set up the car in this post, but I am aware that other settings can be altered to balance out things that are badly set, and that's a bad thing.

For me first step is new points set to the correct gap (normally about 0.4mm)

Then set static timing to about 6 degrees BTDC (before top dead center). Car will start fine.

Then unplug the vacuum advance and use a timing strobe light to set to between the two notches on the flywheel.

Next sort out all the fiddles other people did to the car before you bought it:

Make sure the vacuum advance is working (remove the distributor cap, remove the little black pipe that goes from the distributor to the carburettor from the carburettor. Suck through it and see if the points move and stay moved.

Next for black soot there is a mixture screw on the carburettor. Someone has fiddled with it instead of following the process above. Screw it all the way in and then out by 1.5 turns.

Should be perfect apart from winter when the air intake hose needs to be in the winter setting drawing warm air from the exhaust.

A manual is helpful for this sort of thing. Twisting the ignition timing by 40 degrees seems a bit random, but it is normal if you are a previous owner.

There is no need for any fuel additive if you are not driving at motorway speeds. The additives protect the valves and are not an alternative for setting the engine as it should be.