Diff Lock Function Check

Hi All
I Have a 1989 90 2.5 TD 19J engine (oh dear I hear you all say) which has a few issues,
1.There is no diff lock warning lamp how to I check if the diff lock is working?
2.There is a heavy clonking sound when engaging the clutch, all new bushes have been fitted along with propshaft & Aframe
3.It seems to take a while to start from cold,but after goes first turn of key.
4.What should 85bhp go like, top speed, up hill, acceleration etc
5.How do I check if the Turbo still OK?.
6.How do I check if the injection pump is still good

Any help would be welcome.

1. jack up a wheel with handbrake off and spin it, if spins diff lock not on.
engage diff lock, should lock up. check all wiring too.
2. clock is probably your gearbox mainshaft worn. take inspection plate off rear of transfer box and pull out input gear. look at mainshaft with a torch and check the splines, they will more than likely be worn more than halfway through if its all original. very common problem.
3. starting from cold will take an age as they are indirect injection. no probs there though you could check your glow plugs on a good battery one by one.
4. shouldnt be too slow but they are not the quickest. try and drive another one to compare.
5. take turbo pipe off and check for play in the shaft and signs of damage to the compressor wheel. check for excessive oil in the pipe also. could be a sign of seal failure due to dirty oil.
6. best way is to take it off and get it tested. diaphragm in them is prone to splitting.
Tig

Just had same problem on my '94 110.

Not sure about the clunk, but faulty diff lock light was the diff lock lever linkage. Diff lock was not working. Adjusted linkage and hey presto light works and so does diff lock. Magic.

Thatcherman

Hi Again
All very usefull info thanks, re 2. mainshaft worn a common problem, what can I do about it fixing it.

new gearbox or get someone to put new shaft in yours.