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Ok so here is my issue,

Not long ago I bought a KE70, replaced the carburettor to twin su with lynx manifold, bought new headers etc. It ran once.

Fast forward a week after that when my mate was around and I wanted to show off my mental 4into1 headers and how loud it was, wouldn't start

though I might have been out of fuel, filled it up with some juice, still nothing. after a while of cranking it started, but was minimal (like, maybe 100) rpm, so low you could still crank it and it was ok with it. then it died. 

checked the distrubitor, rotor button was spinning freely, and points had weak spark, no problems. I'll switch it to an electronic distributor, get a bosch module, bosch GT40r coil, electronic dizzy, followed Jackbyo's mad guide to install a new electronic distributor (hence why I went with the coil and module I did) but still no spark, not from the coil, tested it with the old spark against the block or bolt head trick as well. made sure my wiring was all ok, still no spark. Re did the ground leads to the battery neg terminal and the engine earth, still no spark.

Checked timing a million times ( the old rough TDC then rotor to spark lead one in the cap) ((dunno if that helps with anything))

I'm not great when it comes to car electronics, i've read that bad starters can draw too much power and kill spark so I'm thinking that might be my problem?

 

Anyhow, this thing is killing me, the fact that it ran once, but not any more is driving me mental and ive scoured just about every lead I can think of.

So now i'm coming to you lot for advice and hoping that you guys can point me in the right direction in regards to ideas or things ive missed that I should check

 

Cheers in advance!

~Ethan

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I personally wouldn't introduced a new igniton system till you have got the original diagnosed.

what is the battery voltage, static and cranking?

I am thinking the alternator wiring plug may have a poor connection after fitting headers

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So, was it running OK when you bought it and before you did the carb conversion?? Started easily and ran smoothly??

Have you changed the ignition system?

If it is stock, check that you have 12V at the coil while cranking. Remember they have two ignition circuits to power the coil, one that by-passes the ballast resistor for starting and another through the ballasr for running.  Sometimes one will work and the other not. The ballasts do break down.

Anyway, after that check the points gap. If the points are burned with a volcano on one side and a hollow on the other, set the gap without going over the volcano with the feeler gauges. Just use the tips. .  plenty of people have made them too wide by doing that.  If you alter them, check the timing again. Your manual method is fine, but make sure you know which way the rotor turns. No good setting the points timing on the following shoulder instead of the advancing shoulder..

You can check the coil while you're in there by having the points open and sticking a screwdriver across them. The points should spark and the coil fire. If the coil doesn't, make sure there is 12V at the points. If there is, then the condensor is toast, as that is where the electricity for the coil is "stored".

A leaking condensor will not store enough electricity to collapse the coil field fast enough, and give a weak spark.

So, points set, timing set, coil sparking..  it should start with the right fuel/air ratio.

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7000RPM; haven't got a multi meter to check, but will have a look at the alternator wires when I get home from work (y)

Altezzaclub; When I bought it, it didn't start too well with the stock carb, it was missing gaskets and I'm pretty sure it was rebuilt but re assembled wrong, which is why I changed it, because I wanted to go to dual carbs anyway, is struggled and stalled out when it was cold but when it warmed up it ran fine. Have changed the ignition to the bosch module and gt40r coil, if thats what you mean aha, which means I don't have the ballast resistor in it anymore. I'll be getting a multimeter to check if I'm getting 12V at the coil when cranking with my wiring setup how it is tomorrow. As for setting points i'll most likely have to call in a mechanic to do that, as i'm not that confident yet aha

Thanks for the tips and few things to check, will let you know how it goes tonight/tomorrow!

 

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just checking the rotor against the terminal in the dizzy isnt good enough.
that for me, has been the difference between the thing starting, or not starting at all.

Test for spark, by turnign ignition on, , loosen the distributor timing nut and spin the dizzy housing with a spark plug connected directly to the coil HV outlet, and firmly grounded against the chassis first, and then if u see spark then test it grounded against the engine.

If you see spark, say EUREKA, and then set the timing by putting cylinder 1 at 10 degrees before TDC ( as seen on the pulley marking), and make sure its after the intake stroke, by visually checking the valve rockers then slowly turn the dizzy until it sparks and stop right there and tighten the nut. u may need to do it twice.
If u see  a god spark then it means there isnt enough power when the car is cranking, as others have suggested.

If u don't see a spark, check that u are getting 12 V at the coil. if not, fix that. its possible.
If u saw spark when grounded to the chassis but not when grounded to the engine or viseversa, check the earth straps from engine to chassis.
Copper Electrical contacts can go from 100% working to 0% just from one heat cycle.

all this is based on your suggestion that there is NO or very LITTLE spark

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Ok so I've picked up a multimeter, but i reckon the mistake i have made is running a gt40r coil without a resistor. As opposed to thinking it was the gt40 instead, which means rookie mistake and feel kind of dumb considering if that ends up being the case aha. It would make sense because i had weak spark through the old distributor (when you touched the screwdriver against the points with ignition on) which had worn points and was getting weak spark, but after the switch and getting 0 spark the one thing I haven't changed or swapped out is the coil. What do you guys think?

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You might have killed it, its a 9V coil running on 12V without the resistor, but they're pretty tough and you haven't had it running for many minutes.

Run through Google on how to set points, you don't need a mechanic.  The rookie mistakes are-

-not realising which way the dizzy shaft turns.

-not setting the gap when the point's rubbing block is on the top of the dizzy shaft cam.

-not assembling the points neatly so current still flows when the points are open as it leaks out some short-cicuit in the assembly.

You can set the timing a rebuilder says above, that's why you need to know which way the dizzy turns. The points fire as they open when the dizzy shaft cam pushes on the rubbing block, and that is when you see the spark.

So, make sure you have a new condensor, points gap correct on dizzy cam tip, timing set to 10deg, 12V at the points when they are open and you should be right.

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Ok update, got a gt40 coil, but still no spark, ran a multimeter across the points with ignition on as well as cranking but wasn't getting a reading at all. Checked the fise box fuses and replaced them, re went over everything again but still nothing. Its honestly stumped me and is just honestly draining me having no results

 

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14 hours ago, Radical_Jesus said:

....just honestly draining me having no results

 

Don't get all Emo on us!

It sounds like you dont entirely have a grasp on how exactly the ignition system works. I suggest doing some extended reading on how it works.

This is a pretty good start:

http://www.popularmechanics.com/cars/how-to/a6382/4338376/

and here is some info that includes the ballast resistor that we are talking about

http://www.randakksblog.com/ballast-resistors-explained-ballast-testing-procedure/

Remember that points ignition systems have been used on engines from the dawn of time until the late 80s, the k motor system is not unique in any way, same old shit different badge on the back of the car:)

Once you have an understanding on how its supposed to work you can start proper diagnostics. 

easy to check things include:

- Is the coil bolted down properly - it might need to be bolted down in order to ground itself (my 4age one did, cant recall the k motor one)

-Do you get a positive between the + side of the coil and ground with the ignition switch on

-is the points gap set properly as per altezzas post - this is critical

Edited by ke70dave
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