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Patrick Lockyer.
Grand Master
Username: pat_lockyer

Post Number: 1668
Registered: 9-2004
Posted on Saturday, 09 December, 2017 - 04:18 am:   Edit PostDelete PostView Post/Check IP

To-day the engine developed a bad misfire and would cut out, after cooling down the engine would start after a few attempts and had to nurse it back.




Not wanting to destroy another set if a new condenser does not solve the problem I refurbished the old set of contacts.



Fitted a new condenser and the set contacts.
Started and ran ok.



To-morrow I will do some resistance checks on the ballast resistor connections etc.
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Mark Aldridge
Grand Master
Username: mark_aldridge

Post Number: 483
Registered: 10-2008
Posted on Saturday, 09 December, 2017 - 06:36 am:   Edit PostDelete PostView Post/Check IP

Sounds like condenser failure,or coil overheating due to a partial primary winding failure. Have had both in the past ( 6 volt Morris 8). Coil failure could be due to ballast failure, but these usually go open circuit and fail completely.
Mark
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Maxwell Heazlewood
Prolific User
Username: tasbent

Post Number: 123
Registered: 9-2017
Posted on Saturday, 09 December, 2017 - 10:49 am:   Edit PostDelete PostView Post/Check IP

Patrick, as a point of interest, how many miles on the car and how old are these points?
The heel looks a bit worn down which will affect
the dwell angle.
That condenser is new old stock....who knows how long that will last.
As these things age, devices like coils and ballasts should be replaced as a matter of course....working down the ignition chain.
Come on, don't be such a tight arse...chuck another set of points at it
Check the ignition timing while you're at it.
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Patrick Lockyer.
Grand Master
Username: pat_lockyer

Post Number: 1670
Registered: 9-2004
Posted on Sunday, 10 December, 2017 - 12:24 am:   Edit PostDelete PostView Post/Check IP

Mark yes confirmed condenser failure, all else tested ok thanks.

Maxwell, The old contacts have plenty of gap confirms the heel has just bedded in well.
Pix confirms the gap.



Contacts are set at 15th Note old rotor arm.



Condenser new old stock yes better than the failure rate of the new green boxed type.
BTW I always check a condenser before fitment.

new rotor arm fitted.

Only replace a ballast or coil if it shows up a problem.

Dwell set only one turn needed to get 27 degrees.




Dwell variation at revs confirms distributor is in first class order.



Timing always checked after contact fitment or gaping adjustment as a matter of procedure.

BTW I run LPG with no dist vac so will set more. 40degrees at 3000rpm.

Now do I need new contacts not yet.
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Geoff Wootton
Grand Master
Username: dounraey

Post Number: 1876
Registered: 5-2012
Posted on Sunday, 10 December, 2017 - 03:00 am:   Edit PostDelete PostView Post/Check IP

Patrick

How do you check a condenser. Is it sufficient to use a meter and check for resistance each direction or do you have another method that puts a load on the condenser.

Geoff
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Mark Aldridge
Grand Master
Username: mark_aldridge

Post Number: 484
Registered: 10-2008
Posted on Sunday, 10 December, 2017 - 03:15 am:   Edit PostDelete PostView Post/Check IP

Patrick, at least a nice simple ,inexpensive fix,
Mark
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Patrick Lockyer.
Grand Master
Username: pat_lockyer

Post Number: 1671
Registered: 9-2004
Posted on Sunday, 10 December, 2017 - 04:03 am:   Edit PostDelete PostView Post/Check IP

Geoff I use an old faithful Robin analog meter.
the digital will not do.
Using the ohms max in as you say each direction.

A voltage test can be carried out, connect the condenser to a 12v battery for a few seconds, remove the battery and measure for DC volts you should see the same voltage as the battery it will then slowly drop down to zero if OK.



BTW make sure the meters battery is in a good state.

New rotor arm fitted, should have posted it in last thread pixs!

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Geoff Wootton
Grand Master
Username: dounraey

Post Number: 1878
Registered: 5-2012
Posted on Sunday, 10 December, 2017 - 05:43 am:   Edit PostDelete PostView Post/Check IP

Thanks for the info Patrick.
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Robert Noel Reddington
Grand Master
Username: bob_uk

Post Number: 1607
Registered: 5-2015
Posted on Sunday, 10 December, 2017 - 10:01 am:   Edit PostDelete PostView Post/Check IP

My points and condenser are at least 28 years old because I have never actually touched them apart from a nail board pull through, lub and dwell check which is always about right.

I run LPG I have advanced the sparks at bit.
Too much and the engine will kick back against the starter.

Petrol max advance is 36 degrees and for LPG 40 plus maybe as much as 45 degrees.
Unfortunately the dizzy fitted hasn't the range.

The engine starts easily runs sweetly, don't mess with whats works fine.
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Maxwell Heazlewood
Prolific User
Username: tasbent

Post Number: 126
Registered: 9-2017
Posted on Sunday, 10 December, 2017 - 06:15 pm:   Edit PostDelete PostView Post/Check IP

Patrick....that's what I like to see, a man with his finger on the pulse and does things correctly.
If only so may other owners did the same thing, there wouldn't be so many downtrodden and neglected
RR&B's floating around....too much dusting the bonnet but never look at what's under it
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ross kowalski
Grand Master
Username: cdfpw

Post Number: 660
Registered: 11-2015
Posted on Sunday, 10 December, 2017 - 11:01 pm:   Edit PostDelete PostView Post/Check IP

Patrick,

Hear hear on condensers.

Most new ones are junk. I was researching condensers a while back for a Lucas bike magneto ( real evidence for the Lucas myth) and found Bright spark easy caps. They work great and are a lot better in term of vibration and heat resistance.

I also found evidence on the internet that modern condensers are junk. I pulled a couple open to see and yes they are junk. Stick with new old stock, Mallory, aviation ( check capacitance), or Brightspark.

Stay far away from Standard Motor Products modern replacements.

Also,

You're dizzy looks like mine but your dwell adjuster is a rod, mine is a hex. Any idea which is correct?
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Robert Noel Reddington
Grand Master
Username: bob_uk

Post Number: 1608
Registered: 5-2015
Posted on Sunday, 10 December, 2017 - 11:41 pm:   Edit PostDelete PostView Post/Check IP

Patrick said make sure battery in meter is in a good state. Important that the meter is accurate.

Condensers used to be the most reliable bit of the Kettering ignition system
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ross kowalski
Grand Master
Username: cdfpw

Post Number: 663
Registered: 11-2015
Posted on Monday, 11 December, 2017 - 09:16 am:   Edit PostDelete PostView Post/Check IP

Patrick L,

I was looking at your dizzy on the phone ( which I have to do all to often these days) and I can see you have a hex shaped dwell adjuster just like mine.
Ooops.
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Patrick Lockyer.
Grand Master
Username: pat_lockyer

Post Number: 1672
Registered: 9-2004
Posted on Monday, 11 December, 2017 - 06:46 pm:   Edit PostDelete PostView Post/Check IP

Ross, yes 1971-1974 non exhaust emission Shadows in general did not have the Vac advance, starting near SRH 8000 to SRH22117.

At SRH 22118 onwards the opus ignition system was fitted.
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Maxwell Heazlewood
Prolific User
Username: tasbent

Post Number: 128
Registered: 9-2017
Posted on Monday, 11 December, 2017 - 07:06 pm:   Edit PostDelete PostView Post/Check IP

Patrick....in the Jaguar world the Opus was referred to as the 'opeless ignition

The system was notorious on the V12's but it was also in a very hostile environment which didn't help.

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