New to Jags but learning fast

[Doherto]

New and learning fast but need some help please. I have decided to remove engine and gearbox from my recently purchased 1968 240 and do whatever necessary to ensure reliability for future use. However, i have removed the drive train and have them on a makeshift bench for now as I want to remove the head for reconditioning first. But i am stuck. I am attempting to release the tension on the top timing chain, without success. I have lubricated everything over the last two days and managed to get the spring loaded pluner that holds the serrated plate to move eventually. However, the serrated plate will not rotate to release the tension. I removed the plate and then the plunger but still no movement when the plate was replaced. I have inserted a pair of long nosed pliers, as recommended but after levering them with a bar across the handles just bent the pliers. I have tried a few taps with a punch to the plate but nothing and if i increase the punch pressure i am sure i will damage something. Am i missing something, do these things jam over time. Whatever can anyone give me any suggestions how to release the tensioner without causing any damage. PLEASE

[Martec]

Hi,

It is a few years since I retensioned my chains (needs doing from time to time) but it may seem a daft question, have you tried to turn it in both directions? There is a special tool for this job (much easier if the shaft is free) and being tight I made mine, but Ken Jenkins sells them.

If there is no movement then you have found another problem to repair!

Firstly try slackening the bolts holding the chain plate on to see if the eccentric shaft will turn, if not then..............

The normal way of refitting the chains is to turn the engine upside down and with the front pully and cover off, plus the timing gear plate unbolted then slide the crank gear off and the whole chain arangement with it (you will have enbolted the camshaft sprockets first).

Then you can dismantle the gear plate to see what butchery has been done!

As I've said before these are not complex engines, just photograph everything and make drawing and notes and then using an original manual (available on disc I think from Manners or SNG) TAKE YOUR TIME.

Best wishes
Brian

PS on what you have found so far I wouldn't trust your engine as far as I can throw it! you can't do any harm by rebuilding it yourself .....with advise and doing it right.

[Tilleyjon]

Are you using the special tool ?

If that fails you should be able to cut the tie wires on the sprockets to the cams and release these from the cams to remove the head, you cant refit them this way, but you can get them off.

If the engine is seized you may not be able to easily get to both bolts on the sprockets as you need to rotate the engine ideally.

If the tensioner is seized, I'm sure you will have a bunch of work to do to get the engine free, Ive just rebuilt my 3.4, I pretty well did everything to the engine, so it's basically new again !

Jon

[Tilleyjon]

Just had another thought, have you released the nut in the center of the tensioner ?

[Doherto]

Hi, thanks to everyone for your input. For your information, yes i had released the nut , the head came off without releasing the tensioner without too much problem. Block, head, clutch and gearbox now split and the reconditioning of everything starts after our holidays. I am sure i will be back with more questions then. Until near the end of september then,