Might need valve lash check and adjustment. Details are on page 6-5 and 6-22 of the Cosworth Vega Service and Overhaul Supplement. There are copies on ebay. It has been a long time since I have done it but my memory is that it is more tedious than difficult. If any shims need to be replaced you probably need at least Kent Moore tool J-24704 to depress the tappet to remove the adjusting shims. Others here might know a work around since the specific CV valve train tools might be a little hard to find now days. At least at one time the club had some selection of shims. Please be sure the noise is actually in the valve train and not something like a loose belt slapping or poor alternator bushings vibrating or other similar type things. My 2 cents.
Might need valve lash check and adjustment. Details are on page 6-5 and 6-22 of the Cosworth Vega Service and Overhaul Supplement. There are copies on ebay. It has been a long time since I have done it but my memory is that it is more tedious than difficult. If any shims need to be replaced you probably need at least Kent Moore tool J-24704 to depress the tappet to remove the adjusting shims. Others here might know a work around since the specific CV valve train tools might be a little hard to find now days. At least at one time the club had some selection of shims. Please be sure the noise is actually in the valve train and not something like a loose belt slapping or poor alternator bushings vibrating or other similar type things. My 2 cents.