drive chain or drive belt

[Bootneck]

I have a slight knock coming from my drive chain, some one told me the chain is slack, is this possible if it is would it become a bigger problem if not sorted. Myself I do not know much about these things so I would be glad for some advise.

Regards,

[MarkyB]

I guess you mean the timing chain, it normally rattles rather than knocks though.
You can either replace it with the standard simplex (single row) chain or fit a duplex set up with a little light engineering.
The other option is to fit the arrangement from later minis which had a mechanism to take up the slack in the simplex timing chain, the also requires some engineering.

[bmcecosse]

Knocking is not the 'drive chain' - who told you that??? But as above - if you want to renew it, consider the Mini set-up. It IS quiet. The Duplex conversion is for high lift camshaft/silly strong valve springs/high revs etc - and is not necessarily quiet after the 'newness' wears off...... Describe the knocking noise - when does it occur? What oil pressure do you have ??

[JOWETTJAVELIN]

The timing chain rattle is an annoyance rather than a problem. In severe cases the ignition timing is affected. The BMC 1100 Club magazine is, I believe, titled 'Idle Chatter'. Having said that, the sweetest sounding A-Series I ever heard was in a 70-odd thousand mile Austin 1100. Now that was indeed sweet music.

[MColes]

The timing chain I fitted a couple of weeks ago (which wore really badly, really quickly) was making what can only be described as a hollow knocking sound. As it was so slack it seemed to be hitting the timing chain cover.

Never heard a noise like it before but as it was the only part changed recently I inspected and the condition of the chain led me to believe it was that. Replaced it and the noise has gone which leads me to believe it WAS that.

[les]

JJ, You are right the 1100 club magazine was called 'idle chatter' as I recall it actually referred to the idler gear that transferred the drive from the crankshaft to the gearbox below, (being a transverse engine). This idler gear was notorious for being noisy, hence the title. Even more noticeable if an idler gear was used from another gearset.

[JOWETTJAVELIN]

Aha! Thanks Les, that makes much more sense.

[bmcecosse]

Great title for the Mag!

[philthehill]

You can always fit the gear driven camshaft drive produced by Slark Race Engineering. No chain so no problem with slack chain anymore!
I have tried the belt driven set up and to be quite honest it did nothing for me other than provide a constant mist of oil from between the cam shaft adaptor and the vernier adjustable belt pulley (there is not enough pulley to cover the adjuster holes and not enough metal to machine a larger flat on the pulley mating surfaces). Currently have a Kent Cams vernier adjustable steel geared twin row timing chain fitted with the Mini chain tensioner fitted for good measure. Takes time to set up the cam timing properly but it does the business.

[Bootneck]

Hi,

Many thanks for all of the replies and suggestions, thinking about the best option.

[bmcecosse]

The simplest option is to fit a new chain - but I advise to also fit AT LEAST a new crank sprocket - this wears at twice the rate of the camshaft sprocket, doesn't cost a fortune, and should help to preserve the new chain , for a while.
http://www.minispares.com/product/Class ... o%20search
and http://www.minispares.com/product/Class ... o%20search
of course you also need a new gasket, and a seal for the cover..... http://www.minispares.com/product/Class ... o%20search
this seal is 'improved' but seems slightly expensive.... http://www.minispares.com/product/Class ... o%20search

[kennatt]

Just done mine,got it from Tom Roys,came as a kit with chain ,sprocket and gasket

[dalgrae]

After taking a note of advice from Roy about fitting the tensioner type of arrangement I have put together a kit
of parts to do this shortly and have already tried them on a spare engine block by loosely assembling the camshaft and crank to achieve , the problen I had was sourcing the correct type of cover I eventually found one on e bay the other problem is they seemed to have stopped making the pin that is also required so I had to make one.