Ferrari F50 Engine and Gearbox Rebuild

This F50 came to me with 3500 miles on it, and a misfire and lack of power, it also had shifting problems between third and fourth gear and oil leaks from the front of the engine. we removed the complete engine and gearbox unit and completely stripped the gearbox to find that when the gearbox was originally factory built a shim was missing between first and second gear syncro unit and third and fourth gear syncro unit thus allowing the syncro units to separate slightly and the detent balls and springs to come out of third and fourth gear syncro, they were all laying in the bottom of the gearbox, luckily no damage had occurred.

The oil leaks were coming from the front at both sides between the cylinder heads and the block face around where the timing chain goes through the block, this engine does not have a timing chain cover, its all part of the block casting.

When we looked into the history of the car we found that it had recently had an engine rebuild in the U. S. so we removed both cylinder heads for inspection and found that the ‘O’ rings around the hole where the timing chain goes, which is in a groove between the block and cylinder head faces, was not fitted properly causing the oil leaks.

We carried out a rebuild job on both heads, lapping all the valves in and replacing the stem seals. We had to have ‘O’ ring specially made for the groove between block and heads as the original dealer part was not the correct size.

We also notices a lot of loose and decayed pins in the main engine wiring harness so we assessed that to be the cause of the misfire. The harness was restored with all new gold coated pins, around 200 in all, and new rubber weather seals on all the connectors.