timing belt question!

[Gawri20]

was wondering if instead of ordering the locking tool whenever doing a timing belt change, would it be safe just to mark on the pulley with tipex or something where it aligns to and not actually lock the whole thing. that way even if it moves around i can just align it again before putting the new belt on.
yes or no answers should suffice.

thanks

[stevieturbo]

Most engines yes DIY markings and common sense are all that's required.

Some other engines locking tools are essential.

[Gawri20]

stevieturbo said:

Most engines yes DIY markings and common sense are all that's required.

Some other engines locking tools are essential.

why would the be essential? something to do with the arrangement of the belt? or is it just that its hard to mark out

[stevieturbo]

Because some cars you need to remove the pulleys, and there are no keyways onto the shaft they are fitted to.
So special toolings are required to ensure everything is timed up correctly.

[S7Paul]

In my experience it depends on the engine. For most of the ones I've done, the paint mark method has been good enough. However, for the most recent one, which was a Vauxhall 1.9CDTI 150bhp engine, I felt it necessary to use the kit to get everything aligned & locked properly. Without it, it would have been very easy to end up with the belt one tooth out.

[Old Merc]

Over the years I must have replaced 100`s of cambelts,and my next one will be a 24V fourcam V6 with adjustable pulley`s.I have to admit using dabs of paint and other tricks to save time,you can get very blase`.This of course is a recipe for disaster,one wrong move and you have bent valves,lots of them.Just slackening off the outer crank pulley bolt on a Ford Zetec will cause the cambelt to move out of time.Fords,Renault and many others have key less pulley`s or adjustable outer cam pulley`s.My advice is do it by the book and use the special tools and locking pins.

[MG CHRIS]

OP what car most you can get away with using tipex or already have marks to line everything up. But some with floating cams/cranks you need locking tool like some renault engines and ford zetec.

[marcus85]

Never "half a tooth out" with pins.