3t with solexs not kicking over

[joey]

My ta22 with 3t and twin solex carbies aint kicking over I took her for a short drive earlier today and she started and drove no problems. Anyway i was fiddling around with some head unit wiring later in the day and after i had finished that i went to start the car to take her for a quick drive. I gave her a pump or two on the accelerator as i normally do to help kick it over and as i was turning the key it was cranking over but not not starting up!
I Thought most likely it was the battery being close to dead as i had left my door open whilst working on the car and possibly the interior light had drained it. so i hooked it up to my battery charger and went off to work in the falcoon. I got back now and the battery was all charged so i thought id crank it over to see if it started....same problem! The engine cranks over as if it's on the very edge of starting but it doesn't get there. I tried again and kept my foot to the floor incase i had flooded it as its possible that i might have made contact with the accelerator pedal a couple times whilst fiddling inside with the h/u but still didn't fire!
I gave the starter motor a couple of bangs with the hammer to see if that might have been the problem although i doubted it was it as i had it replaced a couple of months ago and it wasnt just making no sound at all when i went to start it, and as i suspected it didnt make a difference.
I checked all the leads from the dizzy and starter and they are all fine. There's about a quater tank of fuel left in it and i can see it in/around the fuel filter and i can hear it being squirted in the carbies when the accelerator is pressed so its not being starved of fuel.
Battery is being charged again as i kept trying to start it and eventually it just drained it.
Anyone got any ideas as to what the problem might be? Is there such a thing as over flooding it or something that it wont start even with the throats fully open?

Cheers, any help much appreciated. Joey

[Night Rider-TA23]

I checked all the leads from the dizzy and starter and they are all fine.

you checked all the leads but did you check they were giving spark...?

[joey]

Sorry for teh noobness but how can i check if its getting spark? probe one of the spark plug wires whilst cranking the engine over? (Just want to try and figure this one out on my own instead of taking the easy way out and calling the racv )

[w810sc]

As Night Rider-TA23 said check for a spark,
on the safe side, use a timing light, but if you don't have one, disconnect one of the leads on the rotor cap using insulated pliers, leave a small gap between the lead and the rotor cap enough so you can see if there is a spark.

[timbosaurus]

Alrighties... the very simplified way of getting any old carbie engine running

You need four simple things.

1) a cranking engine
2) fuel
3) spark, and
4) correct timing

So... to check...

1) you have already said it cranks OK, so your starter is fine.
2) To check spark, you make sure that there is spark at a spark plug. To do this you:
a) remove a plug from the head
b) connect the lead back up to the plug
c) remove all other leads from their plug so it doesn't start on 3 cyls
d) hold the metal of the plug so its firm against the metal of the engine
e) have someone briefly crank the car.
f) I repeat, make sure you hold the plug FIRMLY against the steel part of the engine. The 30,000 volts generated by the coil creates a spark between the electrode and the grounding at the engine. If they are not touching, the ground is made through YOU. You learn that quickly enough
3) if there is spark, and it is still not running, then it is likely fuel. Spark some aerostart down the throat to see if it kicks. Sounds like you're already seeing fuel from the accel pump, so you should be OK.
4) if you have crank, spark and fuel... then you'll have to make sure timing is OK. It's common for a rebuilt or reassembled engine to be 180 degrees out, but since yours has been running, It should be OK.

Therefore, as everyone has suggested, it is likely spark.

Can you confirm that there is no spark?

When you confirm this, you'll then be asked if there is 12V on the + side of the when the key is at ignition.

When you confirm that there indeed isn't 12V , check you're ignition fuse (you've been playing wiring under the dash, haven't you? )

If your fuse is actually OK, maybe the acessory wire you splice into for your head unit... wasn't actually acessory


Cheers,
Timbo

[sillycar chick]

Is this a curse going on?
I went to start 51LII this morning and she didnt start
I was running late so took teh p00trol instead
Mine's been having trouble starting lately, but replaced the dizzy cap because the centre button wasnt springing back and contacting with the rotor. Drove fine yesterday but no startey today
But also mine has been missing a bit lately too, and the tacho going stupid so I think i have ignition problems, I just havent had time to look at it.

So anyway enough hijacking, as others said you need to check for spark....
But can anyone answer this, what if you are getting a WEAK spark? Ive had spark on the last 22 before, but it still had troubles starting... but this was a points dizzy, both 22s now have elec dizzys...

Which type of dizzy do you have? If its points I would be checking the points, they have a tendancy to burn out and just not start....

[w810sc]

pitted points will cause a weak/to no spark at all, if you saw the size of the pit marks i had on my old one you would probably thing i was digging for gold or something.

[timbosaurus]

Yeah, weak spark is a sign of low energy. The energy is stored in the coil and released when the points (or transistor in elec ign) open.

Energy is related to:

a) current flowing through the coil
b) time this current is flowing

a) the current depends on... wiring condition, coil condition, points condition, voltage across the coil, and coil resistance. Nearly all of these deteriorate with age.
b) for a certain rpm this affectively controlled by dwell, which in turn is controlled by dizzy cam lobe and points gap.

So, if you've got a weak spark, replace points (or simply sand pits out as w810sc suggested), fix the points gap and make sure the voltage across the coil is a decent voltage (you may have to measure before the ballast resistor). If this still leaves you with a weak spark, replace coil, leads, plugs, car....

[joey]

Thanks for all the help guys. Tested for the spark and i could see nothing. I followed timbos steps and all is good except instead of earthing to the motor i earthed to the body work because the was no room anywhere on the motor that was metal :s. This should have been a sufficient earth, correct?:


Went and checked the fuse box but there is no ignition fused marked, only engine, and all of the fuses including this one are fine.
My points have a tiny bit of calcium build up so i scraped that away but didn't make a difference.

is 12V on the + side of the when the key is at ignition

Are u missing a word there? Makey no sense to me lol.
Hmmm so whats my next step? Perhaps coil is rooted, any way i can check this?

Thanks for all the help so far guys, Joey

[w810sc]

" are you getting +12 volts on the +ve of the coil".
checking your coil for resistance:
Primary winding resistance = 3.3 ohms (+ve and -ve of coil)
Secondary winding resistance = 8.5k ohms +/- 10% (+ve and center spark plug lead)
Primary winding to terminal case should exceed 50 meg ohms
A coil in good condition should give a spark at least .24 in (6mm) long at idling speeds.

Engine will not fire:
- Discharged battery
- Dampness on leads and plugs
- Cracked leads
- Defective distributor cap
- Defective contact breaker points
- Failure of low-tension circuit
- Failure of high-tension circuit (coil)
- Faulty capacitor

Hope that helps.
fonz

[Neverland]

Hey Joey with the spark plug if you can rest it ontop of the strut tower near the strut bolt say 1/2 to 1cm away that way you have a clean contact with the chassi , where you have it in the photo the plug is not grounded due to the paintwork . If its dark the spark will be easy to see if not get someone to crank her while you watch the spark plug. just make sure you're not in direct contact with the plug and lead... otherwise you'll get a nice suprise

[timbosaurus]

Hey Joey with the spark plug if you can rest it ontop of the strut tower near the strut bolt say 1/2 to 1cm away that way you have a clean contact with the chassi , where you have it in the photo the plug is not grounded due to the paintwork . If its dark the spark will be easy to see if not get someone to crank her while you watch the spark plug. just make sure you're not in direct contact with the plug and lead... otherwise you'll get a nice suprise

Hey Joey,

Don't be lazy, there'll be some engine metal somewhere

But if you do go to the body, just make sure it is on a CLEAN earth like neverland suggested, ie: no paint or rust. Maybe give the strut tower nut a rub with a wire brush, then use that.

Yeah, i missed a word. There should be +12V on the coil + terminal, and continuity to one side of the points (you know the multimeter beep test?) on the other terminal.

When I say 12V, i mean at least "some" voltage. There should actually be a "ballast resistor" (whitish ceramic looking thing on or near the coil) which drops the voltage to aroun 6-8V at all times except crank just to protect the coils longetivity.

[joey]

I shall pick up a multimeter today after work, should find a half decent one that aint too expensive. I'll let you know how it goes.
I also have a dead switch installed in my car from when i bought it. There was a few problems with the wiring in it (similar simptoms) but got an auto elec to go over it and change the terminals so hopefully i can rule out that aswell.
Cheers guys, Joey

[timbosaurus]

Man, don't waste too much money on one. I'm an elec engineer in the automotive field, and even I pretty much only use it to get a rough figure of voltage, current, and continuity.

A $2 super special should even do those tasks

[joey]

Alrighty, bought a pretty cheap multimeter for the task today. I came back home and had another go at the spark check but there was nothing again, just to double check this is what i should have been doing whilst the engine was cranking? (or should i have rested it on the strut bolt against the little electrode at the tip of the spark plug?):


Had a go at reading the voltage of the + on the coil (using DC voltage correct?), was very jumpy, battery died out before i could get a steady reading but from memory was around 3.something. will give it another go in about an hour when the battery is charged. If the coil is ok, then what else could it be!?
Cheers, Joey