|Posted: January 03 2007 at 17:01 | IP Logged
The yard is right. Risers and Manafolds are considered "heavy' maintenance items and should be relpaced together. Over time, the manafold and riser mating surfaces always leak due to age, salt, rust, heat and vibration.
2 to 4 years is the standard life expectancy, some shorter-some longer depending.... They take a real beating under 'normal' use.
Inspect for rust buildup around the head exhaust ports and manafold mating surfaces.
You may want to replace the raw water pump, for good measure, while everything is out and access is good.
Water intrusion is the #1 engine killer, usually coming from manafold/riser leaks. all the best...Roy
Roy & Laurie, S.F. Bay Area
'83 280, hardtop, single 305