help! its killing me

[offroader-rama]

PLEASE HELP



I'll start from the beginning in my 93 gq tb42 I put a crane cams xr700 electronic dizzy optical reader etc... I also put in a crane cams fireball ps60 a 60,000 volt coil with the balast resister as thats what the instruction told me, also i put new plugs with 1.5 gap, it was realy great exept for a flat spot, still waiting for longer rotor from pertronics this may help here or may be the diafram in the gas converter not to worried about that my problem is i took it to a bloke to rebuild the carby he had the car and the carby kit for the day i picked it up at 5:00 and he told me he was sorry but they didnt have the equipment to rebuild carbys (why did he take the job on???) any way he then said i had wired the electronic dizzy wrong and that i didnt need th balast resister as it was only produceing 6v and i needed 12v i treid to explain the the instruction spicified that the balast resister needed to stay in this set up he argued and said he should know and charged me $100 to bypass the balast resister which i didnt want him to touch any i drove the car went great for about 100ks then started breaking down and the tacho would go hay wire
it would come to stop id turn irt over a few time it would start and of I'd go for enother radem amount of Ks and do it again now at th etime iwas on holidays a roverpark and didnt want it ruin the trip so i put up with it till i got home when i got home i tried to figure out the trouble
1. i put balast resiter back in
2. i ran a i wire from battery to resister to rule out ignition barrel
3. i replaced coil
4. i took it back they said the crane cam xr700 was faulty and
that they would give me a report that would clarify for
warranty i didnt care as long as it was replaced they then put a new
set of pionts and condenser so i could drive it to which it cost enother $100.

well i got 15 ks down the road and its still doing the same thing (so its not the crane cams stuff) its being 4 weeks $650 and its the family car and cant be driven
I pulled the dizzy cap of and if i move the shaft side to side i can hear the relays turning on and off with gas flowing to the carby there is about 1-2mm tops of play but i cant see how this is shorting everthing out.

tomorrow I will remove the tacho from coil but i dont think its the problem

PLEASE HELP

[chimpboy]

Did he fark up your carby?

[offroader-rama]

he didnt touch it, he was supposed that all i went there for he had to dick else where and its defenetly electrical

[Hatsu]

Which coil is on it now, the new crane one or the old original one?

[Oscars]

is the xr 700 the top model or cheaper model.

[80lsy gq]

is the tacho an aftermarket one or the standard one...some cheaper aftermarket tachos have a tendency to short out the coil...

the tacho jumping sounds like a short somewhere

dave

[offroader-rama]

its back to standed coil and standed tacho and it does it with both coils
its the xr700 with the led i believe thats the newer better one but its points now and still the same

[Hatsu]

Is the ballast resistor still wired up or have you taken it out?
Also, the tacho can give you some kind of idea of what your ignition system is doing.
What's the needle on the tacho doing when it goes crazy, dropping more to zero, jumping up more to red line?

[offroader-rama]

balast resister is still in
most times the tacho drops to zero but a few times its redlined
i removed the tacho wire and it still did it I'm thinking the safty switch on the LPG could be shorting out sending power back to the negative side of the coil going to try over riding the safty switch.
shame i cant run on petrol to rule whole gas side out

[offroader-rama]

over rode the safety switch no good still no go
correct me if im wrong but i believe a dizzy is all earthed exept the points so why would moving the shaft curse a circut and power up the car unless there was a out side power source I'm smashing my head against a brick wall i took everthing of the coil exept power from the battery and negative to the dizzy and its still no good

[-Scott-]

over rode the safety switch no good still no go
correct me if im wrong but i believe a dizzy is all earthed exept the points so why would moving the shaft curse a circut and power up the car unless there was a out side power source I'm smashing my head against a brick wall i took everthing of the coil exept power from the battery and negative to the dizzy and its still no good

The wire between coil and points should NOT be earthed. The points connect this wire to earth to "charge" the coil, then open to "discharge" the coil (it's not really charging and discharging, but who cares? )

If this wire is intermittently shorting to earth (say, to the body of the distributor) or has an internal fracture which intermittently goes open circuit, that could cause some of the symptoms you're reporting.

Good luck,

Scott

[offroader-rama]

thanks scott but i can rule out a short in the wire from negative coil to points because when i put the electroinic sender in we through all the wire for the points in the bin as the electronic set came with its own harness and when it was converted back to points it had to be rewired and at all times through this prosess the simptyms have not changed

still no go and there is not a mechanic i trust to take it to as i have being robbed to many time by parts fitters

does any one know much about the internals of the dizzy in a patrol as it has to be the fault i cant see how but must be ?? i always thought that if a dizzy was up th shitter it through you timing out not shorted the car

[chimpboy]

Can you try putting in a normal 12V coil and ditching the ballast resistor?

Ballast resistors can fail and they are really not necessary or useful on modern cars imho. Their sole purpose is to improve spark during starting, but the compromise is that you have a shittier system than necessary at all other times.

I think the whole situation is getting a bit confused and it'd be good to go back to basics with this one, ie hook the plus side of the coil directly to the battery +ve (assuming you have a 12V coil) with no ballast resistor, the -ve to the dizzy, and see how it runs.

Have you tried this?

[chimpboy]

i believe a dizzy is all earthed exept the points so why would moving the shaft curse a circut and power up the car unless there was a out side power source I'm smashing my head against a brick wall i took everthing of the coil exept power from the battery and negative to the dizzy and its still no good

I am not sure I understand the question, but if it helps, a distributor works like this:

- the whole body of the distributor is earthed
- as the rotor turns, the points open and close
- each time the points close, they earth the wire that runs to the -ve side of the coil
- this -ve "pulse" is what triggers the coil to fire a spark, and also what drives the tacho

So moving the shaft with your hand could (depending on what point the points are at) cause the coil to power up/power down and make a spark.

Can you explain again exactly what the symptoms of your problem are? You said the car is "breaking down" but it would be good to know exactly what it's doing.

[-Scott-]

Ballast resistors can fail and they are really not necessary or useful on modern cars imho. Their sole purpose is to improve spark during starting,

Yes.

but the compromise is that you have a shittier system than necessary at all other times.

How do you figure that?

During starting, battery voltage is low - can be as low as 7 or 8 volts. So design a coil to run from 7 or 8 volts.

During normal running, battery voltage is up around 14 volts - WAY too high for a coil designed to work with 7 or 8 volts. So, install a ("ballast") resistor in series to "divide" the battery voltage back down.

How to switch it in and out? Install a relay n/o relay, with the coil wired to the starter solenoid and the points across the ballast resistor. When you're cranking the engine, the ballast resistor is out of circuit. When you're not cranking the engine, the ballast resistor is in the circuit.

What's shitty about that?

I am not sure I understand the question, but if it helps, a distributor works like this:

- the whole body of the distributor is earthed
- as the rotor turns, the points open and close
- each time the points close, they earth the wire that runs to the -ve side of the coil
- this -ve "pulse" is what triggers the coil to fire a spark, and also what drives the tacho

Close.

Closing the points allows current to flow through the primary coil. This coil creates a magnetic field, which is also flowing through the secondary coil (so an automotive "coil" is actually two coils, or a transformer.) When the points OPEN, the current in the primary coil is stopped, and the magnetic field "collapses."

As this magnetic field collapses it induces a HUGE voltage in the secondary coil, which creates the spark in your spark plug. All this happens when the points open, not when they close. (There's actually a lot more happening, but I don't know it all that well.)

The tacho signal is taken from the negative terminal of the ignition coil. As the points open and close this terminal is either at ground, or some voltage above ground (connected to +12V through the primary coil.) The tacho counts the voltage pulses, and converts that to rpm.

Check inside your distributor - most have another wire from the points carrier plate to the distributor body. Replace this wire too.

Good luck,

Scott.

[offroader-rama]

you all have confirmed what i thought was right i wont go into detail there dont wont to start a debate just wont the car to go

if I manage to start the car, as its so bad now it hardly starts the revs at idle will go up to a point then drop off by it self to stall, if i try to rev past this point it either comes good for a while or costantly breaks down and the loadest backfire i've ever heard, the neighbers are getting pissed of when the car is playing up the tacho just drops up and down spazmaticly to nothing out all most times but a few times its redlined ( tacho not engine that is) so it has to be electrical!!!!!!!!!!!!!!!!!!!!!!!!!!

i have gone back to basics + from battery to + coil - from coil to points all new wires have tried with and with out balist resister i have tried three coils has done it with electronic sender tacho on tacho off etc...

ITS FARKIN SPASTIC OR I AM ( no coment needed there its not a question)

[chimpboy]

...

[chimpboy]

I would like to know why you're so sure it's an electrical issue and not a fuel-air issue.

It does sound a little bit like really whacked out fuelling on the LPG setup.

Not saying this is the problem, but based on the symptoms I wouldn't be ruling it out.

Also, in all the stuffing around, could you have got the timing WAY off by now? If you have pulled the dizzy right off at any point, I think you need to reset the timing because it could quite easily be a long way off.

[offroader-rama]

first people please dont turn this into a debate as its not necessary its not an ego chalange so no quoting unless its relivant to my problem not how nasa got to the moon in hollywood

what is necessary is my car going, please and thank you

and i believe its electrical mainly because of the tacho going so wacho especialy when it redlines with the car stalled ie. not running and tacho past 7000rpm
and i bypased the LPG safty swich and relays/solaniods and it still does it when it first started i thought it was the LPG but i stronly rule it out now !? but thanks anyway

[chimpboy]

and i believe its electrical mainly because of the tacho going so wacho especialy when it redlines with the car stalled ie. not running and tacho past 7000rpm

Hmm, I am just trying to think whether this could be the result of hooking the battery directly to the coil... if the dizzy happens to stop with the points closed.

I don't think so but on the other hand... hmm. With the engine off, if you put +ve and -ve from the battery directly to the coil, does the tacho go whacko? Does it redline? If so then it doesn't point to an electrical problem really.

Also, you didn't answer my timing question... are you sure you haven't got the timing way off now? I've done this myself on occasion, it really messes up fixing the original problem!

[offroader-rama]

offroader-rama wrote:
and i believe its electrical mainly because of the tacho going so wacho especialy when it redlines with the car stalled ie. not running and tacho past 7000rpm



it did this after it had being running smoothly for a short time and the tacho working proply then bang it went off again ??????

[chimpboy]

Sorry mate this is a bit of a toughie.

I think you need to start at the start.

Set the static timing.

Check that the coil is producing spark ie disconnecting the coil ignition wire at the dizzy, and holding it in place somewhere near the head/block, then hooking the +ve side to the battery, and "tapping" the -ve side with a grounded wire. If you get a fat blue spark, then the coil's okay, otherwise it's not.

Adjust points etc.

Check firing order is right.

Check the condition of the spark plugs.

Really all the basics for getting a spark. You could check for spark on all spark plug wires too, once it's running (even if roughly).

It's fiddly but you've been at this so long you need to check the basics thoroughly imho.

Just my thoughts.

[offroader-rama]

the plugs and leads are less that 1500ks old and some times it run trouble free so the fire order is right I'm going to try another coil lead tomorrow to rule that out but I'm not going to replace the whole set because its not just missing its more than that ???

[chimpboy]

the plugs and leads are less that 1500ks old and some times it run trouble free so the fire order is right I'm going to try another coil lead tomorrow to rule that out but I'm not going to replace the whole set because its not just missing its more than that ???

I wasn't saying to replace them, just check 'em all. But check the timing first unless you really haven't moved the dizzy during all this.

[killer_garden_gnome]

id take it to (or goto if it wont drive) the ones that did the gas work or if not take it to someone who knows the shit when it comes to gas, at least u can rule out a gas issue. i have heard of the gas solenoids playin up i know u said u checked but maybe while it runs it plays up

[offroader-rama]

its not the gas as i had it idleing on petrol today and it was all over the place same as gas i couldn't rev it on petrol as the exlerater pump is rooted and i have had 5 cars on lpg so im fairly familiar with it and had solenoids play up its different.
but thanks

and the dizzy has being out twice and the timing is around 12 degrees advanced ???????

[bazooked]

jsut a stab in the dark, is ur gas convertor stuffed?

[chimpboy]

I think you should put this thread in general tech.

[shakes]

I'll start from the beginning ....it was realy great exept for a flat spot, ........bloke to rebuild the carby he had the car and the carby kit for the day i picked it up at 5:00 and he told me he was sorry but they didnt have the equipment to rebuild carbys (why did he take the job on???) any way he then said i had wired the electronic dizzy wrong and that i didnt need th balast resister as it was only produceing 6v and i needed 12v i treid to explain the the instruction spicified that the balast resister needed to stay in this set up he argued and said he should know and charged me $100 to bypass the balast resister which i didnt want him to touch any i drove the car went great for about 100ks then started breaking down and the tacho would go hay wire

flat spot = needed a tune
did it do it before you took it to this "mechanic"?
have you returned the wiring to "original" and started from scratch.
re-read chimpboys posts!


now for some random shite off the top of my head, could be way off...

these dont explain the dizzy but....

Gas convertor could be gunked up?
Mixer might have a pinhole in the diaphram?

The taco has been wired into the wrong section of your new igtn module?
Shaft play in the dizzy... warms up, bushes loosen, jumps around everywhere shorting on everything?
Cracked Dizzy cap/housing?
Dizzy loose?
Triple check timing!!
timing chain/belt tensioner loose/broken?
I've never had a TB42 apart but it also might be a good time to invest in an oil pressure guage just in case it is something internal!

Carby rebuild kit $50
manual $50
6 cans and some time in the shed... priceless


Simon

[MART]

This might sound stupid but is the little contact in the centre of the rotor cap still there as sometimes they pop out and the power can only travel through spring to contact rotor button , happened to a mates mini , had symptoms like yours , might help , Cheers Paul.