7 replies to this topic

[firstforward]

I have what I can only describe as a noisy tappet but I think it is a noisy cam follower. I say that because I have dialed out all the clearance in the tappets one by one and the noise is always there albeit very slightly reduced, but further to that my question is, can a cam follower be very noisy and later the noise virtually disappears.

 

I can do a 20 mile motorway run and afterwards on idle, it is quiet or less noisy, another time it really clatters, definitely from around the rocker cover.

 

Any ideas?

[jaydee]

Could also be worn shaft/rocker pads

[KernowCooper]

Run the engine up to temp, insert a small feeler gauge of 2-5thou in the rocker and see if it goes quiet when started, keep hold of the gauge though, and its not difficult to do as all the viva engines were done with the engine running. If it goes quiet suspect worn rockers.

[Dan]

  A lightly worn rocker shaft or bush would give tappet noise that changes with oil pressure, and so with engine revs and temperature.

[Captain Mainwaring]

Run the engine up to temp, insert a small feeler gauge of 2-5thou in the rocker and see if it goes quiet when started, keep hold of the gauge though, and its not difficult to do as all the viva engines were done with the engine running. If it goes quiet suspect worn rockers.

I forget how you were supposed to do this but remember doing it.....strange to look at the old 1256cc engine and see it was pretty close on power to the 1275S engine.....I had a Viva once, the brother of the owner of Centre Point hit it in his Rolls Royce and drove off - I ran around with it stoved in for ages - the exhaust was made out of click together hoover pipe.

 

For the 10 mins it takes to pop the rockers off you can see if they are worn or if the rocker shaft has any wear - I don't recall A series engines being as bad as B series, but B's used to crack the bottom of the tappet itself, making it noisy however tight the clearances were adjusted.

[Captain Mainwaring]

Easy way to check if the shafts worn, is to set the valve clearances then start the engine for a few minutes let it cool and recheck the gaps. They will have tightened up/loosened off if the shafts worn.......

That will happen anyway. It only takes a few minutes to pull the rocker shaft off, you can slide the rockers over on the springs and measure 'em up if you have a micrometer.

[Dan]

  I have to say that it is quite poor practise to remove the rocker assembly unless the head gasket is going to be replaced.  It is of course possible to pull the shaft without lifting the posts, but it is also possible to move each rocker to the side without dismantling anything if the spacers are still springs and have not been replaced with solid ones.  Then the shaft can be inspected, the wear would be on the underside.  The fit of the rocker bush onto the shaft can also be felt (although not very accurately) once the rocker has been slid to an unworn section.

Edited by Dan, 23 May 2013 - 03:56 PM.

[firstforward]

OK guys thanks for your input, I shall be on that this weekend.