Camshaft change on td - keep belt on?

[BX Bandit]

Is it possible to swap camshaft s on a td without removing the cambelt? I.e. to use the two locking bolts to secure the cam shaft sprocket and swap camshafts leaving the belt in situ?

[mat_fenwick]

I can see absolutely no reason why not - I wouldn't use them to lock the sprocket while you undo the securing bolt though; best to use the square section on the shaft.

[JayW]

The only issue i can see is lifting the camshaft to a high enough angle to clear the "bearing" castings when the sprocket is pretty much fixed in the vertical position. Assuming the cam and sprocket seperate easily.

[mat_fenwick]

Hmmm, I think that will be an issue, but you could always wire the spocket to the belt (same with the pump sprocket for safety) while you remove the cam.

[Defender110]

Yes I would do this /\ or at very least tipex mark the belt and pulleys to show their corect position if it slips.

[rutter123]

you can use cable ties on the top 2 sprockets and lock the flywheel with a 7mm drill bit or hex key, you will prob find that you will still need to release the tensioner to give enough clearance to lift the cam out that first inch or so.

[mat_fenwick]

I think you'll be all right really, as I've taken the camshaft out of a scrap engine without removing the cambelt. I obviously didn't take particular care in preserving the cambelt position though! Just undid the cam bolt and levered the sprocket off - probably putting a bit of extra tension on the belt in the process, but if the cam bearing caps are loose the other end can move upwards and release a bit of tension.

[BX Bandit]

Thanks for he thoughts guys, I hadn't thought of what Jay mentioned. I ask as despite the car starting the button, there is plenty of whiteish smoke when doing a 'rev test' like they would in mot. I may well of advanced the pump too far, but it could also be a valve clearance issue as I didn't ave a thin enough shim to give adequate clearance.
Also, when on cold fast idle, she gently hunts for an even idle for a minute or two, so I'm also wondering if I have an air lock in the pump giving my timing issues, I know cav pumps are very sensitive to this.

Apart from those relatively minor issues, see Pigeon Restoration blog.......

[mat_fenwick]

Let me know if you need any shims posting down mate, I've got a few spares.

[BX Bandit]

That's kind if you mate, I may take you up on that, but they must be cheap as chips, are they available singly?

[mat_fenwick]

I've only ever had to buy one, and that was about £4 five years ago...would get pricey if you needed all eight!

[citsncycles]

What I ended up doing with a couple of the shims on Timex where the clearance was too tight was grinding them down with a bench grinder. I checked first that they weren't case hardened, and on careful examination could see that some others had been done previously.