Learning to Tune

Well mine is 46.5 degrees. Hardly varies at all ....maybe 1/10th degree lower, but pretty much constant. What to say?

As for setting my carby - I dunno - it's not playing the game. See - my Series 1 handbook says to turn the idle screw so the revs are higher than normal, then let the mix screw out (richer) until it hunts, then screw back in till stable, then lower idle again.

Seems to be so much variation in where I could estimate this that I can't tell if it's even close.

Doing the Martin method only seems to result in rough idle, and it needed richer....guess I'll just have to plod away.

On a sadder note, in order to try to check my mix setting, I took out plug #1 to check the colour, and it appears to be wet....looks like oil, so now I assume something has been buggered on a new engine build.....sad Scallop. :(

My mix could well be too rich....I read that this can cause "wet fowling".....if mix were the reason, wouldn't all the plugs be wet? I just find it hard to believe that 400 odd miles on a not properly tuned engine has wrecked something....

Firstly Dan I expect that the wetness on the plug is fuel. You are only adjusting the idle mixture here, once the throttle is opened fuel is drawn out of the main jet by the air passing through the venturi and the idle circuit is bypassed. If there is that much oil in the cylinder you would have blue smoke out of the exhaust.
I assume the main jet has not been changed, so regardless of the idle quality or mixture, once driving the mixture will be the same as before.
In regards the idle mixture setting, without getting too technical, simply try to find the smoothest idle. This will be the correct, or close to, mixture regardless of position of the mixture screw.
Cheers, martin

Well, I appreciate everyone's help, but I am totally frustrated and confused. I guess this is why the internet rarely produces mechanics.

Hang in there Dan, practice should produce a great mechanic.:)

Cheers, Mick.

Hi Dan,

As Martin said just back there you seem to be a little bit confused about what the mixture screw adjusts. It only adjusts the mixture for idling.

Inside most carburettors there are three separate circuits that work together, the idle circuit, the main circuit and the acceleration pump circuit. The idle is only in use when the throttle plate is closed or almost closed. In this situation the normal carburettor circuits can't work as there is not enough airflow and petrol put in above the plate will not necessarily work as well as when the plate is open. Therefore idle circuits are separate and usually put the petrol in under the plate. Pretty much as soon as you open the plate and you raise the revs above idle you start to use the main circuits though the transition is usually gradual, not an on or off situation. All this is controlled by airflow and the resultant vacuum that creates. The main circuit which is used during all normal running is controlled by fixed jets that can be removed and replaced with different ones but are mostly not adjustable in place (some carburettors do have adjustable main jets but the Landrover carbie is not one of those). So what you are adjusting with your idle mixture screw is only used for a very small part of the running of the engine and is very, very unlikely to have damaged anything. The accelerator pump circuit just gives an extra squirt when you very first put your foot down on the throttle so again does not effect general running though may cause stumbling when the accelerator is pressed.

There are a number of different ways to set the timing on the engine and all of them work if you know what you are doing. I can set timing with points without a test light as you just look for the spark and that is where you tighten up the dizzy. However I can see no reason to have points in this day and age. I don't really care what the "purists" would have to say about that :) but why not put an electronic module in there and never have to worry about setting points again? Can't even be seen from the outside so no one realises you have changed anything but you get a much more reliable set up.

And the way that Martin suggested for setting the idle mixture is a perfectly good way and should result in a good idle if followed properly.

Cheers,

Tim.

And, if your dwell is at 46.5 deg then your points are open too much, which could result in poor spark. Set it to the correct 60 and see what happens, particularly if you have a standard coil then I would follow the standard setting. Higher voltage coils might require something slightly different (perhaps the 52 earlier suggested) but again, put an electronic module in there and forget that dwell or gaps exist :).

I don't have a dwell meter so don't use one.
Look at the back of the engine and you will find a cover on the top side of the flywheel housing swing the cover back and you will see a pointer and that coincides with marks on the flywheel.

First set your points to 15 thou", turn to each lobe in turn and measure each one looking for any variation due to wear in the distributor, reset the so the 15 thou" is the average and then put the 4° advance mark on the flywheel so it meets the pointer.

The slot in the clamp holding the distributor body should be halfway and the vernier set on the large mark, with the main clamp loose turn the ignition on.

Then turn the body of the distributor so that you move it the same direction as the rotor so when the points are closed move it slowly back the other way towards the direction of the rotation of the rotor button, listening carefully for the click as the points break open, check by softly wiggling the rotor shaft you should hear the points arcing at that point, tighten the clamp off and arrange your leads to suit the firing order.

Then go for a drive.

Oh that excess fuel, check the level of the fuel in the float bowl, before mucking about with jet settings.
.

Well, had a better day with the little one today. Trial and error adjusting the gap set screw, put the dissy cap back on, start her up and get the dwell to as close to 60 degrees as I can.

Took about 20 goes....

Sitting on 61.6 degrees now. Ran out of light and sense of humour trying to get her just below 60.....maybe try another day

Played around again with idle mix and finally got her idling sweetly! The wetness was fuel. Appears OK now.

Took her for a drive, now back home.....she's running like a Boss!

I've got 2 sets of points to run through, and when I have I'll move over to electronic ignition. It's a suggestion that I've had from more than 1 trusted soul.

Thanks everyone for taking the time and effort to help me - again. I appreciate it.

https://www.aulro.com/afvb/images/im...014/02/964.jpg

Don't sweat on the numbers. 61.6 deg is more than close enough. Most dwell angle specs are +/- 3deg. The 60 deg figure from Land Rover is a compromise which is arrived at after many hours of testing. You've done well!!:D