As always when working under a Car make sure it is well supported.
Do not rely on a Jack whether Manual or Hydraulic.
A Scimitar landing on you will give you a sense of humour failure.
Please Note. This information relates to a SE5a. There are differences with some early SE5s but the principles are the same.
All pictures are expandable by clicking on image.
This information assumes that the hydraulics are in good condition. Any leaks or seepage past the Master or Slave Cylinder seals should be sorted as no amount of adjustment will cure problems if the Hydraulics are not good.
Also there could be a problem with the pipe that connects between the Master Cylinder and Slave Cylinder. This pipe is made of plastic and over the years this pipe losses is rigidity. This results in what could be a confusing problem. If you are able to select gears without to much problem when the engine is cold but you have difficulty selecting gears ( especially first and second ) when the engine is hot the problem could be with this pipe. The reason is when the pipe gets hot the plastic gets softer and when the hydraulic pressure is applied ( when the Clutch Pedal is pressed ) the pipe diameter expands with the pressure and so there is less flow of hydraulic fluid to operate the Slave Cylinder. There has been some debate about this effect, all I will say is that I have seen the effect and replacing the pipe cured the problem. When replacing this pipe it is a good idea to replace it with Stainless Braided Hose. They can be obtained from someone who deals with Hydraulic Hoses ( Look in The Yellow Pages phone book ). If you bring the old Plastic Pipe they will be able to use the ends assuming they are not damaged. The ends are the threaded bits that screw into the Master and Slave Cylinders.
The two nuts on the shaft that comes out of the Slave Cylinder are the ones to adjust. To get at these you will need to remove the plate that is attached to each side of the chassis ( Two bolts each side ). Once this plate is removed you will now have access. There should be a spring that attaches to the Lever that goes into the bell housing and onto somewhere near the Slave cylinder. I say somewhere near because this is in an area that if a previous owner has been the spring could have been replaced and hooked anywhere in the area. Take note that if the spring has been replaced and the replacement is to strong it will push back the piston in the Slave Cylinder and after adjustment if the spring does push the piston back into the slave cylinder you will get excessive movement of the Clutch Pedal, be aware of this as it can cause confusion. The tension of the Spring should be just enough to pull back the Lever that goes into the Bell Housing against the adjustment shaft.
Adjustment requires removal of this spring. When the Lever is pushed away from the Slave Cylinder ( Once spring removed ) the Lever should have a small amount of play between itself and the nuts on the shaft that comes out of the Slave Cylinder. The amount of play is adjusted by the two nuts. The one nearest the Lever should have a rounded edge that fits into the Lever, the other nut is to lock together. The amount of movement should be about 1/16 inch. Not to critical except if there is no play/movement the Lever will be pushing the release bearing against the pressure plate inside the Bell Housing creating excessive wear. It the play/movement is to excessive there will be difficulty selecting gears especially first. Remember to refit the spring.
The Slave Cylinder can be seen above with the plate that needs to be removed to gain access.
The adjustment nuts can be seen on the left of the shaft near the Lever.
Note the spring that has been disconnected from the Lever, the hole can be seen in the lever.
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There are a number of reasons why adjustments are required. One reason could be wear in the Clutch. This can result in difficulty selecting gear especially first gear. As advised above when adjusting make sure that there is a little play/gap between the lever and rod. To much will result in difficulty selecting gear, no play/gap will result in excessive wear especially the clutch release bearing.
Another problem with the Clutch could be slipping. This could be noticed when pulling away or changing gear. If you notice the Engine revs increasing but the speed of the Car not increasing with the revs it could be the Clutch slipping. This could be wear of the Clutch Friction Plate or there could be contamination of the Friction Plate. This contamination could be from a leaking rear Crankshaft Oil seal. If this seal is leaking engine oil will leak past the seal and onto the Friction Plate. If Oil is leaking past the seal it can normally be noticed by oil dripping from the bottom of the Bell Housing. There should be a plate bolted to the bottom of the Bell Housing and leaking oil will be noticed. Have a look at the picture below to see what to look for.
The Plate can easily be remove to inspect. There are four bolts holding the plate, note that one of the bolts holds the bottom of the Slave Cylinder. Removing this plate will show if there is an oil leak. The removed plate can be seen below. Note that there is a possibility that the plate may not have been refitted by a previous owner.
If there is oil in this area the only option is to replace the Clutch and oil seal. The seal is held in place by a piece that is bolted to the rear of the engine block. The flywheel will need to be removed to get at this area. Once the clutch is removed the flywheel can be removed.
It seems such an easy comment to make to say remove the Clutch and flywheel but this requires the gearbox to be removed from the engine. By far the easiest way is to remove the engine and gearbox in one go, I realise that not everyone has access to lifting facility's so the gearbox can be removed from the engine while still in the Car. To remove the gearbox while the engine is in the Car click here.