Noisy cams
Posted: February 20th, 2011, 8:37 pm
Hello.
I own a 1969 Fiat 125 with the original 1608 twin cam with 80000 miles.
I recently had a full recondition of the engine with new oversize pistons etc. The head was reconditioned too with new guides and seals. The whole engine is "standard" other than Marelli electronic ignition from a Fiat 131 and the oversize Fiat pistons.
Since owning the car for 4 years I have always been aware of cam/bucket noise. The clearances were checked and maintained at standard 18 thou for inlet and 20 thou for exhaust.
I recently decided to fit 2nd hand 1608 coupe cam shafts (9.6mm lift from the original 8.3mm) to increase top end power and obtained a set which I fitted myself with the help of the seller who is a mechanic. He told me the cams were checked by a cam specialist who confirmed they are "good". The noise is now much worse than before and on checking the clearances have found them to be slightly less than specified in the 125 manual. Can anyone advise if the problem could be caused by the cams themselves being worn or the clearances being too tight? Any help would be greatly appreciated. The cam boxes have been machined at some point.
I own a 1969 Fiat 125 with the original 1608 twin cam with 80000 miles.
I recently had a full recondition of the engine with new oversize pistons etc. The head was reconditioned too with new guides and seals. The whole engine is "standard" other than Marelli electronic ignition from a Fiat 131 and the oversize Fiat pistons.
Since owning the car for 4 years I have always been aware of cam/bucket noise. The clearances were checked and maintained at standard 18 thou for inlet and 20 thou for exhaust.
I recently decided to fit 2nd hand 1608 coupe cam shafts (9.6mm lift from the original 8.3mm) to increase top end power and obtained a set which I fitted myself with the help of the seller who is a mechanic. He told me the cams were checked by a cam specialist who confirmed they are "good". The noise is now much worse than before and on checking the clearances have found them to be slightly less than specified in the 125 manual. Can anyone advise if the problem could be caused by the cams themselves being worn or the clearances being too tight? Any help would be greatly appreciated. The cam boxes have been machined at some point.