Base timing

[Bern]

Hi All,

I've got a back fire when changing gear above 3k rpm (ish).

Searching the site here it looks like it could be down to ignition timing.

However all references to Base timing seem to point to the WikiLEC, but that doesn't seem to be available!

Can somebody give me the basics for setting the timing, I've got a strobe light, and I guess there are pointers on a pulley on the front of the crank!? And there's no distributor to adjust!!

Thanks in advance,

Bern.

[rip]

I assume you have a turbo? The following will probably not be correct for an NA.

The timing marks are not the easiest to see, but they are in the usual place. You may be able to see them by turning the steering to full lock right, but it will probably be easier to see them by removing the wheel.
You will need to put the ECU into service mode or else it will try to counter adjust your adjustments. To put it into service mode, locate the ALDL (Assembly Line Diagnostics Lead) plug. It is a 10 pin plug in the passenger cell behind the glovebox. It should be clipped out of the way in a holder.
Start the engine then short out the black & white wires. A paperclip is ideal for this. The check engine light should now start to flash steadily.
You should now be able to use your strobe light to check your timing. The gradations on the block are quite easy to make out but the nick in the pulley is not.
On the cylinder head at No 4 end, you will see the Cam Angle Sensor (CAS) assembly. You can adjust the timing with this in exactly the same way as you would a distributor. Its pinch bolt is underneath & takes an Allen key (about 6mm I think).
The correct timing SHOULD be 16 btdc although mine runs a lot better when set to 32 btdc. I cannot explain this but I've checked it with Elanscan & no knock is detected.

Once you have set it, take out your paperclip & blip the throttle a couple of times. When the revs have settled, replace the paperclip & check it again to make sure the timing has settled in the same place.

These engines are very fussy about timing so you should have loads more power once your turbo starts to provide some boost, so pack your tools away, go for a drive & prepare to enjoy it.

[Giniw]

Here it is: http://wikilec.com/view/Base_Timing

[dapinky]

Bern,

The 'powers that be' are aware of the broken WikiLEC link, and it *should* be fixed soon.

In the meantime, there is a 'ghost' copy of the site at http://www.Wikilec.com - but it is an older version and may not be correct.

That said, the base timing article hasn't changed (or been updated) for a long time, and can be found here.

EDIT - beaten to it by Gini whilst typing

A couple of extra tips (which i find useful, but others find unnecessary).

As RIP says, the timing marks are not easy to locate - it's a tiny cut in the edge of the pulley, like it has had a light pass with a hacksaw blade

I found that by removing the wheel, locating the mark and then replicating it on the oposite edge of the pully it made it easier to find when you need it. Also a dab of tippex on the mark helps (and also on the 16deg mark on the gauge).

I then lined it up at 16deg, and then put another timing mark on the pulley (2 adjacent hacksaw nicks) approximately 100 degrees clockwise - where it lines up with a suitable spot on the engine casing (which i also scribed to line up).

Now I have additional marks which are at 16deg, but far easier to see with the wheel on the car, so ideal for a quick check of the timing.

With the car on the ground it is not always easy to line up the 'proper' timing marks whilst viewing it 'straight on' and holding the strobe lamp so that the light is also straight on to the marks.

Also, before you start it is worth putting 2 strips of masking tape along the CAS bracket and cam cover, and using a pen to mark the starting position - it makes visualisation of the movement a whole lot easier, and allows you to put it back 'as was' very quickly.

On other tip which I incorporated in the car when I first got it was a simple small rocker switch (hidden inside the top of the glovebox), with wires spliced into the 2 wires onto the back of the ALDL plug - then to get it into and out of service mode is just a case of operating the switch from the drivers' seat... this is of even greater benefit if/when using Elanscan as you can plug in the lead whilst it is in service mode - something that can't be done otherwise as the paperclip gets in the way

[Bern]

Wow, such great responses!

Many thanks chaps, I'll hopefully get a chance to look at this over the weekend.

Cheers,

Bern.

[GeoffSmith]

Get yourself up to Castle Combe on Saturday and Dave will give you a hand...

[Giniw]

As RIP says, the timing marks are not easy to locate - it's a tiny cut in the edge of the pulley, like it has had a light pass with a hacksaw blade

I marked it with tip-ex so that it's viewable through an alloy hole with not too much parallax (enough for a quick check when you have already set it by yourself).

[dapinky]

Bern,

Anyone who can keep an MGB on the road can cope with an Elan

[Bern]

Dave,

I certainly hope so, but how did you know???

[GeoffSmith]

1971 you say…

Say hello to Tim Pryce-Jones from me.

[dapinky]

Dave,

I certainly hope so, but how did you know???

Can't say too much (But I may know some people in Easton & Crosscombe) - Oh, and Norton Radstock.......

[Bern]

1971 you say…

Say hello to Tim Pryce-Jones from me.

If I knew who he was I would!!

[Bern]

Thanks all, timing is now sorted - was on about 8 deg btdc.

Cheers,

Bern.