I have a 85 380 SL with the double timming chain. The rail broke bending all 4 exhaust valves on the left side and breaking the valve cover. The chain looks ok but the car has 150k miles. Should the chain be replaced? And if so do the gears need to be replaced also. I can not see any wear on the gears or chain. Does the timming chain cover need to be removed to replace lower rails and remove any chips from the broken rail. If I have a shop do this what should it cost and what would be the difference of just rails and heads verses rails chain gears and heads. 1 last question Can you replace all the rails without pulling the timming chain cover and do they all need to be replaced. I really appreciate your time concerning this matter.

Thank you Robert Schweitzer
rds1000@msn.com