Inlet Manifold

[ayr41]

Could someone kindly tell me in laymans turns how I get the inlet manifold off so I can replace the three vac-hoses that go underneath the manifold, thanks in anticipation ~ Stephen

[Rich H]

Crikey.
OK, I'm doing this from memory, so apologies if I've missed something.
Usual working with petrol rules apply, disconnect battery, fire extinguisher, yada yada

Remember 'in front' refers to towards the front of the car.

Start by removing the air filter housing

1. Disconnect all the fuel hoses from the fuel distributor (careful not to loose the cu washers)

2. Disconnect the plug and two vacuum hoses from the vacuum solenoid tucked in front of the fuel distributor (be careful not to get the hoses mixed up when refitting)

3. Disconnect the electrical connector from the idle speed motor. Remove the two allen bolts securing the idlespeed motor to the inlet manifold.

4. Push the idle speed motor toward the front of the car which will help pop the tube off the front of the cold start injector manifold.

5. The idlespeed motor is an absolute git to refit so note the arrangement of injector pipes and ignition leads around the idlespeed motor brass pipe. Then with a turning and pulling action pull the idlespeed motor and brass feed pipe clear of the inlet manifold.

6. Remove the throttle spool cover plate (if fitted) one M7 bolt holding it to the inlet manifold

7. Remove the wire clip securing the throttle push rod ball joint to the underside of the throttle spool. Pop the push rod off the throttle spool.

8. Remove the two M7 bolts securing the throttle spool to the right hand side of the inlet manifold

9. Remove the short M7 bolt securing the throttle spool to the top of the thermostat housing. Disconnect the full throttle microswitch electrical connector and move the throttle spool and bracket clear of the inlet manifold, you will not be able to remove the throttle spool entirely since it will still have the throttle cable connected to it.

10. Remove the very long M7 bolt which secure the middle of the throttle tubes (ram horns) to the throttle body.

11. Remove the remaining three M7 bolts which secure the throttle tubes to the inlet manifolds and remove the throttle tubes.

12. Remove the two allen bolts in the 5 and 7 o'clock position securing the metering assembly to the inlet manifold.

13. Disconnect the connectors on the idle switch.

14. Lift the metering assembly clear of the inlet manifold.

Nearly there....

[Rich H]

15. Disconnect the electrical connector from the top of the cold start injector.

16. Remove the two vacuum feed pipes from the cold start injector manifold

17. Remove the single bolt securing the cold start injector feed pipe to the bottom center of the inlet manifold and withdraw the cold start injector.

18. The inlet manifold is secured to the block with four M7 bolts. They are situated between the three cylinders on each side of the engine....

WARNING. Be VERY careful how you remove these bolts. If they are seized in the block, they will snap off in the block leaving you with a big problem (ask me how I know ) do everything you can to remove these bolts without snapping them!

19. Withdraw the inlet manifold from the engine.

20. Relax. :lol:

First time round, having never done it before, the job will take you a good few hours. It takes me a couple of hours on a 'fresh' engine where everything is seized up and needs cleaning.

The three vacuum pipes are connected to a thermoswitch on the left hand side of the coolant Y pipe. Be careful when removing them. Try GENTLY prying whilst twisting them rather than tugging at them. The plastic on the thermoswitch is brittle and will snap easily if you are not careful.

With the manifold removed you will see the six 'o' rings on the inlet ports are squashed flat. They will probably leak when you refit the inlet manifold. I strongly advise you replace them otherwise you'll have vacuum leaks all over the place.

With the inlet manifold removed now is a good time to clean out 'the valley of death' and check the condition of the steel heater feed pipe which can become severely corroded. Also check the condition of the rubber hoses to the back of the water pump and notice what an absolute doddle it is to get at the distributor and the bleed nipple on the clutch slave......an so the list goes on.... :roll:

[Guinney1971]

great 'how to' there Rich - worth submitting to the Magazine if you ask me

[ayr41]

Many thanks for that Rich, I have sent you a PM.