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#1 Series 3 ignition

Posted: Sat Apr 08, 2017 7:59 am
by flyer295
I'm having trouble with getting the engine started for the first time in many many years. I have re-built the engine (the original was destroyed and replaced with a XJS HE engine.)
I have checked the timing 12 deg BTDC with mark on the rotor opposite the pick up
The timing sequence is correct
The No. 1A TDC is on the compression stroke
New high torque starter, new battery, but it still turns slowly.
There appears to be no suction on the carbs when turning it over.
The balance resistor is getting HOT (don't think this should happen should it ?)

The engine is on a test rig prior while bodywork is being sprayed, so no air filters or exhausts, just the down pipes.

It did run once for about 15 secs but not again since.

I know that the original ignition system was notorious for it's unreliability.
Has anyone had any experience with Lumenition ignition on these V12's. as an alternative?
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#2 Re: Series 3 ignition

Posted: Sat Apr 08, 2017 8:23 am
by MarekH
Dear Bob,

Overall timing is typically quoted with reference to the timing pointer mark on the crank damper and you check that on a running engine using a timing light.

The amount of vacuum or centrifugal advance added to any static advance may be quoted at the distributor, which makes one full rotation per two rotations of the crank, but there is no way to check the distributor on a running engine - you check its effect using the timing light on the crank damper again.

The correct timing information is in the manual and on websites like Roger Bywater's AJ6 website for both HE and pre-HE engines.

With a high torque starter motor, your engine should turn over at about 160rpm.

kind regards
Marek

#3 Re: Series 3 ignition

Posted: Sat Apr 08, 2017 10:00 am
by jagwit
How are you supplying fuel?

Are the chokes operational?

Have you measured compression?

#4 Re: Series 3 ignition

Posted: Sat Apr 08, 2017 10:03 am
by jagwit
flyer295 wrote:I know that the original ignition system was notorious for it's unreliability.
Has anyone had any experience with Lumenition ignition on these V12's. as an alternative?
My car is running on Lumenition and pulls strongly all the way to 6k rpm.

#5 Re: Series 3 ignition

Posted: Tue Apr 11, 2017 9:07 am
by Woolfi
Which heads has this HE-motor now, when working with carbs ? The original HE-heads or the heads of the pre-HE motor ?
Regards Wolfgang Gatza