Timing chain oil seal 1200 herald metal encapsulated or rubber? and other matters

[Tipidave]

Hi all,

Having returned from a great trip to Le Mans with the herald, the oil leak from the crank/ timing cover is now leaking quite badly. Having searched around I see that two different seals are available. A rubber only one as supplied with the timing chain kits and a metal encapsulated one (NA329). Which is correct? or are they interchangeable? Is one better than the other?

Also, I intend to take the opportunity to replace the Chain and tensioner but would prefer at this stage not to muck about with the sprockets. The engine will need a rebuild in the not too distant future but cannot be tackled now due to lack of funds... Other than visual inspection for asymmetry on the teeth is there any other way to appraise the condition of the sprockets? What else should I be looking for before inserting the new seal? 

Thanks again for all the help and advice

Regard

David

[johny]

Hi, be aware theres two different sizes of seal and I think you'll need the smaller one. Ive always used rubber encapsulated ones and think these are easier to install in the metal cover plus ensure a better seal in it.

If the chain is within the wear limit I would leave it, then in the future replace chain and sprockets together as these wear to suit each other. Sprocket tooth wear assessment is done visually and you can compare them with photos online of new ones. The tensioner however is a routine maintenance item and if yours is going to wear through before the planned overhaul replace it... 

[Pete Lewis]

i have found some seals dont fit well they are much deeper than the cover and the seal fit is poor 

cant remember if the rubber or steel boddied, but distant bells lean to the metal being best fit 

Pete

[Colin Lindsay]

If i remember correctly the larger seal is for the GK series engines only (definitely engines in the 13/60 range anyway) so 1200s are all the smaller. Try for original new old stock metal versions, they're always a good fit.

[johny]

16 minutes ago, johny said:

Hi, be aware theres two different sizes of seal and I think you'll need the smaller one. Ive always used rubber encapsulated ones and think these are easier to install in the metal cover plus ensure a better seal in it.

If the chain is within the wear limit I would leave it, then in the future replace chain and sprockets together as these wear to suit each other. Sprocket tooth wear assessment is done visually and you can compare them with photos online of new ones. The tensioner however is a routine maintenance item and if yours is going to wear through before the planned overhaul replace it... 

Another thing is to closely look at the running surface of the seal (pulley?) as if theres the slightest groove leakage will be increased. If this is the case try to ensure the seal lip runs in a different place...