why wont the timing chain stay tight ??????

john2666

i have done the timing chain (one of many) on a veccy b, i timed it up put the tensioner in, all seemed right nice and tight on all sides, manually rotated 360 and the chain is jumping, checked it all and even though the tensioner is on full and brand new it is still leaving a bit of slack on the left hand (exhaust) guide rail, any ideas guys?

john2666

Can the chains stretch?

vocky

you can only turn the engine by the crank bolt, otherwise the chain will jump

john2666

i was vocky, with the tensioner in there still seems to be a little play in the guide rail though :eh:

vocky

which guide rail, the one for the tensioner will be loose until the tension is released on the tensioner (remove the tensioner and check it's tensioned, you will find if it's correct you will need to apply moderate force to start the threads)

john2666

hi Vocky, it is the tensioner guide rail, i have screwed the tensioner in fully and still a little play, enough to make it jump a tooth, i didnt need to put any force to start the threads though, when you say the tension needs to be released on the tensioner is there a special way to do this? i pushed the piston in on the tensioner it is on the first 'click' so it stays together and when i push the piston in it springs out again as it should the tensioner is brand new :?

vocky

the tensioner should not be on any clicks (the internal ratchet), when the tension is fully released you need to use some effort to fit the tensioner to the head

john2666

right.... i will do it first thing in the morning, will it re adjust itself when the engine is started?

vocky

once the tensioner is released it's automatically adjusted :thumbup:

john2666

how does the tensioner release?

vocky

get the tensioner and press it down onto a bench / something solid, you can feel thats it's released :thumbup:

ps: it will then be 'sprung' when you push it down

john2666

did that, and built it all back up again, all seemed fine then cranked it over, it went to fire then the F******n chain slipped and done the valves in again.... I have done plenty of these and never had this problem. so i now have a 51plate vectra 2.2 hatchback going on ebay for scrap or down to the scrappers cos its done my head right in !!!! anyone want any bits...cheers for your help on this one Vocky

vocky

thats very weird notsure.gif