seeping head gasket?

[guest]

I have a slight oil seep coming form the the rear head gasket. I am using cometic steel 0.030 head gaskets on a mild build. Is this going to cause a problem? ie a head gasket blow out. was not there for the first 3500 miles after replacing the heads but just started thanks guest.

[Mike]

Oil leaks on the Cometic MLS gaskets is very rare and typ. due to incorrect head bolt torque. If the oil leak is an indicator of inadequate head bolt torque, then a failure is what follows. If the gasket fails, this can lead to "torching" of the cylinder/head/piston. We have seen at least one case where head gasket cylinder dowel o-rings (as used on stock 88ci head gaskets) were used with the MLS gaskets. This can cause the above problem over time as the o-rings get pushed out, relaxing the torque on the heads. The Cometic MLS, HD 95ci composit and SE MLS gaskets DO NOT use this o-ring.
Make sure the oil is coming from the gasket and not the exh. port. A leaking exh. valve guide seal can appear to be a head gasket leak because the oil runs to the same low point on the cylinder/head fins. This is very common on early 05's (updated valve guide seals are available and supplied in gasket kits dated after Aug. 05). However, the heads must be removed in either case, so the work is the same (with additional time required to replace the valve guide seals in the heads, once off).
Thanks, Mike