[Vwdiesel] Retorquing streach head bolts

[William J Toensing]

Very interesting. I hadn't heard this before. This may explain the head gasket leaking that my 1983Datsun/Nissan Sentra diesel had at 50,000 miles & my Mazda 626 diesel had at 50,000 miles. I recall with both cars that with streach bolts, you didn't have to re torque the heads so both cars didn't have this done when I put 500 to 600 miles on them nor was this done on the Mazda after the head gasket was replaced at 50,000 miles, & failed again at 70,000 miles. This time, I insisted the head be retorqued after I put 1,000 miles on it & the head gasket went over 120,000 with no problem. I think the problem is most mechanics don't know how to deal with the special requirements of diesels due to their high compression. This is one of the great values of a forum such as this. I wonder if this could be the reason for the high rate of failure with the GM Olds V-8 diesels?