Hi, Tourist.
If after changing the battery does not resolve your starting problems
Check to see if you have a GOOD connection to the injection pump FSV (fuel shut-off valve), this connection is prone failing/breaking (Its best to solder the wire to the little 'Banjo' shaped connector for good continuity) if this fails there is NO power to energize the Solenoid within the FSV and therefore basically the fuel delivery is shut off and the engine will NOT start.
Also the FSV on the injector pump can fail (Lucas pumps seem to be more prone to this problem than the Bosch units from my experience) to check this (Without removing the FSV) remove the little nut from the top FSV and then with the ignition on remove the 'Banjo' connector from FSV and then just touch the thread end connection on/off a few times & listen for a 'Click' from the FSV, if you can it should be okay if NOT the FSV will need replacing. If your happy with that and alls okay move onto the glow plugs by removing them all and checking their performance/condition, unless you already changed them recently.
But that's NOT always a good guarantee to think each individual glow-plug is performing as it should !
Don't get fooled by thinking there new or nearly new and's all's OKAY
As I found out one occasion, I was having starting problems so i went off to HALFORDS for a new set of Glow-plugs I replaced them and everything was great for approx. two weeks then after the third week starting the car up got more difficult and the after approx. 4-5 weeks the car would NOT start up at all, I just ended up flatting a good fully charged battery

So I decided to remove all the glow-plugs and three out of the four were completely dead,
I took them ALL back and got a FREE replacement set put them in and all was well so there you have it !

WARNING PLEASE NOTE
A very quick and simple way if you don't have an AVO meter to check the condition/performance of your glow-plugs.
The following method of doing this check MUST be done outside or in a garage with NO combustible material of Inflammable liquids about , also I suggest you use a pair of leather work gloves as glow-plugs get EXTREMELY HOT and STAY HOT for a considerable time (If there working properly)
UNDER NO CIRCUMSTANCES DO THIS INSIDE YOUR HOME (For obvious reasons)
By using a good fully charge 12 volt car battery and with one end of a jump lead croc. clip to the + terminal on the battery and then carefully connect the other end of the jump lead to the same connection as the fly-lead connector connects to on the ends each glow-plug when fitted into the cylinder head.
Then BE VERY CAREFUL with the next step, touch the body of the glow-plug to the - terminal of the battery to see its it glows up quickly 5 to 12 seconds say, if the tip of the glow-plug isn't glowing up and is apparently cold replace that one with a new one

Likewise if your just getting a slight glow in the middle portion/shaft of the glow-plug or just a slight glow on the tip replace it with a new one.
Glow-plugs MUST glow up fairly quickly and produce a white/yellow glow from the tip to a faded orange half way up the glow-plug tip/shaft to ensure good starting characteristics

Also check this thread out for more possible problems or checks you may have to carry-out to resolve your starting problems:-
http://www.bxclub.co.uk/forum/viewtopic.php?t=9948
and also:-
http://bxclub.co.uk/forum/viewtopic.php?t=4207
Cheer's and best of luck .