Ignition

So remember my hot start problem on the 72 RRC?

well just got it back from the garage after they set up the carbs which now work a treat but the starting issue still there and doesnt seem too much to do with it being hot anymore/if ever.

What they reckon is its igntion not carb related as when your cranking it wont start but if your clever and knock the key back one notch while it spinning over it fires up straight away.

Like its not getting a spark whilst cranking

They asked about a ballest resistor and I remember when Stu was fitting the lumention kit for me he said the ballest wasnt there as it was already running a 12v coil.

Any ideas guys?

check your earths

which ones in particular?

The garage did wonder if it was lumention related, do you know if they have an earth?

I have to be honest elektrickery even at this basic level fooks me up

battery starter chassis. i had similar issues on my old motor, seems starter is pulling all the juice, not enough left for ignition. my prob started with hot engine and got progressively worse

interesting , stu had to put a new starter on as the old one was too big to clear the new exhaust!

Mind you it did it before that , pretty much only from hot and only since the lumention and carbs went on.

the carbs are sorted a treat now tho lol - the choke actually has an effect

I reckon its gotta be lumention related- it used to start on the button when on points even with totally fooked carbs

put a volt meter on + coil and check voltage drop while cranking,check battery drop to ,you can try running wire from battery direct to + coil see if thats better if is run better wire from ingnition source with less voltage drop ,

ok, bearing in mind I am an electrical novice with a multimetre here:

switch mm to volts put red probe on +coil and black on body and measure whilst cranking as oppsed to just with igntion on?

second run a wire direct from +battery to + coil and see if its better , if it is rig a up a permanent wire? wont that mean the coil is always on and will get cooked?

the way its set up atm/from new is with all the postive power cables coming off the starter . the earths are on a post by the bulkhead body mount near it. the only other big guage earth is the one form bat neg bolted throught the inner wing.

not for permanent running but to try and rule out different things ,its normal to get voltage drop while cranking thats why some not all coils were 9 volt with std 12v lead run thru reistor to get 9v for coil ,it could be poor wiring ,starter etc but it helps to see what the drop is ,and wether fresh supply off batery helps if so you can check wiring ,or move on to illuminition amp

ok , thanks

I wont get to do this till tomorrow or sat but any idea what drop would be ok and what wouldnt?

also which things should I not connect to avoid wrecking it :doh:

This has possibly been checked, but I have not seen it mentioned.

If the ignition is too far advanced, it will not start when hot.
Just a thought as I saw the ignition had been changed to lumenition.

Has it been checked with a strobe?

course you could connect the wire from starter to coil you forgot to fit/thats broken..(white and purple)

bison4x4 said:

This has possibly been checked, but I have not seen it mentioned.

If the ignition is too far advanced, it will not start when hot.
Just a thought as I saw the ignition had been changed to lumenition.

Has it been checked with a strobe?

Click to expand...

yeah its been strobed by stu and was spot on thanks for the idea though

zen said:

course you could connect the wire from starter to coil you forgot to fit/thats broken..(white and purple)

Click to expand...

Thanks zen , they must think your telapathic

I cant see one tis true but I havnt had a good look yet

I just ordered a new lumention amp module at stus suggestion and hes comin friday to try it, if not we think it must be down to the wiring somewhere.

I will have a look for the magic wire tomorrow, what part of the starter should it come off?

BTW just to check my sanity I went and tried the funny starting/key trick again and it really does work so its obviously dead keen to fire up with just the inertia left on the engine, stupid elctrickery!

fair enough but i would have checked voltage drop and other first you need to know as many facts as possible when sourcing fault ,otherwise its guess work ,you dont take feed direct of starter theres plenty of other places ,it may well be module but you really should check values first

Yeah I am gonna have a try with the +bat to +coil wire and see if it fires up

To check the earth, simply get a decent quality jump lead and connect it to the - terminal on the battery and clamp it to the case of the coil - if it still doesn't start - it isn't the earth.

Alternative simple check - get a 12v bulb, put the + to the coil lead, - to the car body (or jump lead as above).

When you put your ignition on, it should be lit, when you turnover to start it should flash a little.

Hope this helps,

Ok guys finally got to work on it today.

First job , wire from +bat to +coil and she fired straight up no funny key business or anything

Then a few people had said to me about the purple and white wire from the starter to the coil to avoid the drop to coil on cranking.

Chris was kind enough to come round and show me the wiring diagram and follow the wire round for me , we then found it coming from the coil all the way to the starter to a very dodge bit of choccy block then to a black wire which wasnt connected but had the old spade connector which used to always fall off the old starter.

It looks like stu has wrapped it up out the way and as he is coming on fiday, and may have done it for a reason, I have left well alone for now.

Looks like that new lumention module may have to be returned if I am lucky

fett said:

Chris was kind enough to come round and show me the wiring diagram and follow the wire round for me , we then found it coming from the coil all the way to the starter to a very dodge bit of choccy block then to a black wire which wasnt connected but had the old spade connector which used to always fall off the old starter.

Click to expand...

Aw shucks it was nothing

Although it is 99% that the White /Purple wire is the problem, it would be worth getting Stu to check the continuity at both ends to make sure.

Also, with the ignition on, check the voltage from the White/Pink wire at the coil as this is the original Ballasted wire. I suspect you will only have 6 to 8volts supplying the coil if the wire is doing its job. Laying in a new ignition fed 12v supply will give a bigger bang for your bucks.

Cheers

Chris

Thanks Chris, stu rang today and is poorly atm so wont see him on fri :doh:

I hope hes coming soon afer that as I need the car next week. if not then I may have to get you rind to show me what to connect the starter end to lol

ok no luck getting stu back to fix it before I need the car!

ran a wire from his red wire on the starter solenoid to the + coil today and she starts on the button but then shuts down after a second or two so i guess my guess at wiring is wrong.

I took his red wire off and put the old pink and white ballast wire on there and I had nothing then.

so whats missing here?