Timing chain

[Bit of Both]

Hi
I am busy restoring a 1960 Morris Minor. On the clock it has 55600 miles. The engine still runs well and a compression test showed it was still in good order. My question is whether to change the timing chain or not? How do one determine when to change it?
Thanks

[bmcecosse]

Yes - change it and fit new rubber 'tensioner' rings, maybe also a new crankshaft sprocket - since it does twice the work of the cam sprocket! And of course a new seal in the timing cover.

[chickenjohn]

Surely you only need to change the chain when it gets very worn and noisy???

It is extremely rare for a chain on an A series engine to fail. It is not a consumable item like a can belt.

[PSL184]

Difficult one to call.... It's less than £20 for all the parts required and a half hour job, so on that basis, why wouldn't you? On the other hand, apart from noise, they rarely give any issues. The noise is due to the useless tensioning system employed which will become noisy again in a very short space of time anyway, unless you fit a proper tensioner from a Mini engine.

[chrisd87]

Little point in changing it, unless it's become noisy. Even then, it's very unlikely to let go - to my knowledge there's only one report of it happening on this board. In the incredibly small offchance that it did, the engine is of the non-interference type, so all that would happen is you'd grind to a halt. Valves would not hit pistons, etc.

[MarkyB]

a half hour job

With the engine on the bench maybe, I doubt it could be done with the engine in the car so fast.
I wonder what the "book" time for the job was.

[PSL184]

I doubled the time it took Roy to do one roadside in his best Sunday clothes

[MMaurice52]

The timing chain is 52 years old, replace it!

Timing chains DO wear out (stretch). A worn T chain can cause a cam to crank timing to be "out" by 10 degrees cuased by stretch. It's such a low powered engine, why allow those valves to open and close out of time?

Marc

[PSL184]

The timing chain is 52 years old

Might not be - Might have been replaced a week before the previous owner sold the car

[bmcecosse]

The only information we have is that the car has done 55k miles...... And the OP is asking if the chain should be changed, so I rather assumed it could be heard rattling.. YES - fit a new one !! And yes - the Mini tensioner etc is much better - but also not inexpensive. So for most purposes - a new chain + rings + crank sprocket will do the job nicely.

[Bit of Both]

Hi
Thank you for all the replies. I only heard the engine run for some hour and to be honest it was the first time that I have ever heard a Morris engine run. I would therefore not know whether it is noisy or not. As I am currently in the restoration phase, where the car is totally stripped and the paint is now being stripped, I thought that I might consider changing the chain if necessary as the radiator etc. is out of the way.

[mike1864]

Only last week MMOC's Tech Advisor told me the duplex chain was worth going for (complete with sprockets and two countersunk screws) especially if the engine's stripped down anyway.

[bmcecosse]

The duplex chain is NOT worth going for It's for high lift cams and/or extra strong valve springs. The best way forward by far is to fit the Mini tensioner system. That's why MG/Rover did it! It IS quiet and stays quiet and doesn't cost a fortune. But a simple new chain + rubber rings + crank sprocket (it's a mistake to penny pinch by not changing that wee sprocket) will be good for many thousands of miles happy motoring on a standard engine.

[MarkyB]

For my money the duplex chain is a good upgrade, very easy to fit and extends the chain life far more than double as one might expect.
Instead of being over stressed like the simplex chain it's a bit under stressed and retains the original look.

[bmcecosse]

But it will rattle at idle, which the Mini system doesn't.... My current long suffering engine has it - and it rattles.

[chickenjohn]

The other concern I would have over changing the chain for the sake of it is the dubious quality of many modern parts! Are repro timing chains as good as the original 1960's items??

[MarkyB]

Not much you can do about that except buy a named chain.
The original chain was clearly not up to the job as it's virtually a service item.

[Callum97]

Could any of you direct me to a site or dealer from whom I could buy a mini chain tensioner. Would I run this with a standard minor timing chain kit, or with a full mini timing chain kit? Thanks, Callum

[philthehill]

The kit of parts you require to fit the tensioner is available from MINI SPARES (Pt No: MSSK051). It contains all the parts you will need as regards the chain.
You will also need to find a suitable timing chain cover (Pt No: CAM4641 or CAM4904) to accommodate the tensioner.
If you can find a good S/H one so much the better. They are available new at £80 inc VAT.
Currently 4 on 'e' bay ranging from £10 - £20. Listed under 'Mini timing chain cover'.

[bmcecosse]

The cost of new covers is just terrifying! You can run the tensioner against a standard Minor chain/sprocket combo - but they are likely to be worn - so may as well fit all new.