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Technical Carburettor mixture base setting?

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Technical Carburettor mixture base setting?

RDS said:
Hello Jack

re: Dead but not short circuited condenser usually means very hard to start engine or no start at all due to weak spark.
Engine starts well with 2-4 pumps of the accelerator pedal (prior o start) to re-set the choke.

Re Ballasted coil: no, this is a nominal 3 Ohm coil (actually 2.7 Ohm primary but I have added additional heavy duty resistor to bring up to 3 Ohm, no difference though anyway). NB I do not think the UK model uses ballast coil ignition.

re pump: I tested valve leak and it is ok, pumping rate however was not testable. easy to test with an electric pump, less so with the mechanical pump fitted, annoyingly.

RDS
Click to expand...
I spotted from earlier posts that currently have non ballast coil fitted(-:
Was wondering if the is a ballast hiding somewhere in car.

With ignition on and points closed what is voltage at coil +ve ?

Strongly suggest using original coil if you still have it.
don't know what is going on with your current coil secondary windings at 20,000 ohms. 2.7ohm primary should not require a 0.3ohm resistor in +ve feed just adds another component that could fail.



Gunson lo gauge can be used to check fuel pump pressure and they are quite cheap to buy.

Are the pipes on carb attached correct way round if carb has a return pipe to fuel tank?
 
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Ah yes, sorry, you did see the non-ballast fitment.

I don't think there is a ballast resistor in the system because the voltage at the -ve side of the coil is +12v. ie no voltage drop over a ballast.

Yes can revert to original coil, will do!

Ref the secondary coil resistances, i had another from the same supplier which has 70,000 Ohm resistance. How's about that then?!!

Additional resistance can be removed.

Not sure of how Gunson lo gauge connects; Tee in?

Hose connection: this has concerned me also: no indication the pump for inlet and outlet but a suck/blow test indicates which to use ie spigot next to fire wall, though another model eg from Eurosport is the opposite!

Inline carb filter clear, thank goodness.

RDS
 
70,000 ohm secondary coil resistance , I would think faulty coil.
Great you have original coil.
Great you don't have ballast resistor, points must be closed or coil - ve must be grounded for voltage check to prove no ballast resistor.

Does your carb have a pipe comming from the fuel pump and another pipe on carb going back to fuel tank?

You could tee in lo gauge to fuel pipe between pump and carb or when engine cuts out remove fuel pipe at carb connect lo gauge and crank engine on starter.
 
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faulty coil: that's what I thought so called the technical dept. They said not a fault....!

yes voltage drop with the coil grounded, sorry.

yes there is an overflow hose from the carb back to the tank. All are clear/free or obstruction.

Tee in ok ta!
 
RDS said:
faulty coil: that's what I thought so called the technical dept. They said not a fault....!

yes voltage drop with the coil grounded, sorry.

yes there is an overflow hose from the carb back to the tank. All are clear/free or obstruction.

Tee in ok ta!
Click to expand...
Wow an acceptable range of 20,000 to 70,000 ohms what was going on?

Confirmed no ballast resistor then, very good.

The pipe from carb back to tank is to reduce / prevent vapour lock in pump and hoses. Great pipe is not obstructed.

Is pipe from pump to carb connected to correct inlet on carb?
 
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my response to the supplier exactly. And that 70,000 Ohm item one was they sent to replace the 20,000 Ohm one when i queried it.....

Pump to carb hose: yes thankfully the carb has a lovely large arrow to the correct and larger spigot.

As a related matter: the internal diameter of the existing hose from tank to carb is 6mm and is really stretched over the pump spigot. An 8mm i/d hose fits better so i will replace with that and may dispense with the in line fuel filter for a trial before i cut the hose down.

there are arguments both ways as to where the inline filter should go: before the pump to protect the pump internals and after the pump because it is a better pusher than puller. Someone (not me) must have done the experiment?
 
RDS said:
my response to the supplier exactly. And that 70,000 Ohm item one was they sent to replace the 20,000 Ohm one when i queried it.....

Pump to carb hose: yes thankfully the carb has a lovely large arrow to the correct and larger spigot.

As a related matter: the internal diameter of the existing hose from tank to carb is 6mm and is really stretched over the pump spigot. An 8mm i/d hose fits better so i will replace with that and may dispense with the in line fuel filter for a trial before i cut the hose down.

there are arguments both ways as to where the inline filter should go: before the pump to protect the pump internals and after the pump because it is a better pusher than puller. Someone (not me) must have done the experiment?
Click to expand...
That is funny, you had a 20,000 ohm coil which appears wrong, so the supplier sent you a 70,000 ohm coil and said that was ok, super wierd.

I would say put the filter somewhere you can access it reasonably easily .

There is a filter screen in the tank to protect the pump.

Did you remove and check the filter inside the carb near the fuel inlet under a big brass nut?

As there is return pipe to tank from carb , measure fuel pressure by disconnecting fuel feed pipe at carb and connecting it to lo gauge.
 
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To be more exact, i queried the 20k coil but indeed yes it was weird. They were no doubt making a point....

Easiest access place for the in line filter is just after the sender unit along the firewall.

Yes the internal carb filter is clean as a whistle. So is the "sock" pick up filter in the tank and also the tank itself. The only thing I am not happy with there is the new float has a little fuel in it and is about to be replaced with a fiat 500 float if it will fit. Hence i get a max reading of 3/4 tank.

BTW the tank breather is clear.
 
All looking good with fuel supply then.

Do update us when you switch back to old coil, fit one wire between battery and coil +ve and one wire between coil - ve and distributor.

PS what did you set points gap to?

Which distributor do you have S135 s155 s178 ?
 
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yes think so.

diz is s135

will do.

The preparation action and cut -out action lists are getting longer and longer for this issue, and time/traffic are the limiting factors. I gave up today due to the rain. More excuses follow for tomorrow....
 
RDS said:
yes think so.

diz is s135

will do.

The preparation action and cut -out action lists are getting longer and longer for this issue, and time/traffic are the limiting factors. I gave up today due to the rain. More excuses follow for tomorrow....
Click to expand...
Don't worry you are getting there.

(-:

Rain, where in UK are you?
 
the price of the s178 is prohibitive even if you can adjust the dwell from externally. i wonder if the s135 can be re-engineered for that. But anyway, I hope to go back to the Powerspark/Pertronix/Accuspark WITH a functioning tacho when i have sorted this issue.

Which makes me think re the "weird issue" mentioned in an earlier post:
has anyone fitted the Powerspark/Pertronix/Accuspark module AND suffered tacho problems? We may be onto something here.....

to get SW from me, with 45 minute breaks would take a while...
 
Noooooooo dont try and mod for externally adjusatble points gap.

I had a distributor on mk1 panda with the same externally adjustable points as s178 , very expensive points! It was rubbish and unnecessarily complicated.
These are only 4cylinder engines and as such dwell is not as critical engines with more cylinders.

If you ever near Gloucester let me know, you are welcome to visit and show me your x1/9.
 
cheers jack - agreed and most appreciated.

RDS
 
PS don't put more than one condenser in the circuit at a time.
 
funny you should say that; i had considered (for a moment) to do a very quick change over of coils on the road, adding a cold coil to the "hot failed" one in parallel to see if the car would start. Clearly, i won't be doing that either.
 
Yes do that it's a great idea.

Just don't use more than one condenser at same time
 
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