Timing Light Mystery

[jamesdennison]

The short version - 

My timing light won't fire on no.1 but does on the other cylinders.

I am getting a spark at no.1 (I have one of those testers where you can see the spark)

Any ideas?

..... and does 18 degrees BTDC on a Triumph 2000 ME engine sound right - this is what haynes say.

 

Longer version - my car has been backfiring from the carbs.  This is possibly due to 95 petrol as that is all I could get last time I filled up but I thought I'd go back to basics and check the timing.  Set the tappets from cold first - all good.  Come to check the timing using a strobe light on no. 1 and no flash.  Shifted over to no.2 and it works fine.

I've used a spark tester and there is a good spark on no. 1 but still no flash.

My next step will be to change the HT lead ... but weird as there seems to be a good spark.

Any ideas?

.... The car is a bitsa, GT6 chassis, spitfire body with an ME engine from a 2000.  I've recently acquired a haynes manual for the 2000 which says 18 degrees BTDC.  This is different to GT6 timings.  Is this still the wisdom?

Thanks in advance!

Cheers

James 

 

 

 

 

 

 

 

[jamesdennison]

Just had a thought.  The spark I can see on the tester occurs when the electricity jumps the gap in the tester and only shows that electricity is getting to the contact on the top of the spark plug not that i'm getting a spark on the electrode at the end of the plug itself.  I reckon the spark plug is faulty.

Will swap them tomorrow, fingers crossed that sorts the backfiring too.

[Pete Lewis]

ME  2000 engine is static 10 deg btdc    for 97+ ron     18 is way too much especially for 95 ron

Stick to 97+ if possible   on 95 retard to around 8 deg.static 

I would expect 18 to spit back thro the carbs 

Pete

[jamesdennison]

Thanks Pete.  It is set at 8 deg at the moment which is why I questioned Haynes.

I'll get hold of some new plugs and see if that is the issue...

[AidanT]

I wonder if this is the same reason mine was playing up @ twiddle day?  Mine is also an ME mk2 2000

No performance issues though on mine. What about yours James?

Aidan 

[Pete Lewis]

Engine prefix has no connection with wandering or missing sparks 

Aidan  we didnt try yours at higher than idle,    max figure is around 28-31 deg btdc at 3000 rpmVac off, 

If you have a strobe try that see ifnthe leaping mark stabilises

In fact any speed above 1500  so all the bob weights are working see if it steadies the leaping marks

Pete

[JohnD]

James,

if your strobe won't fire on No.1, then suspect the lead, not the plug.   Swap leads around, see if the fault follows the lead.

And have you got your 'spark detector' fitted when you try to use the strobe?   Try without.

JOhn

[AidanT]

Pete i agree - it was just an interesting coincidence it's the same ?

 

 

Aidan 

[jamesdennison]

Changed the plugs - £10.50 incl VAT for 6 so no hardship ...... and all seems to be working again.  Strobe is firing off nicely and car sounds a lot better.

Not been able to drive it yet as my wife's just come home and blocked me in!  but I reckon the plug was the issue.

Timing is at 8 degrees but my distributor has a fine adjust twiddler on it so very easy to change the profile up (or is it down?) a few degrees without getting the spanners out.

Hopefully that's sorted...