Datsun Roadster Parts from Rallye Enterprises, Ltd.

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Datsun SPL310 - SPL311 HEADBOLT INFO Originally the cars came with 9 headbolts that were one length, and one bolt that was longer, to make up for the loss of thread length that the bolt that holds down the engine pulling hook incurs. A huge amount of mechanics and owners did not realize this, and put the longer bolt in a hole without the engine hook (or a stack of washers) under the bolt head. The result would be the torque wrench reading that the bolt was "tight" but actually the bolt was hitting the bottom of the hole. After a length of time the head gasket would blow out at that point. If I had a dollar for everytime someone has called me the last 25 years and said their head gasket keeps blowing at a different point... In the past we have just sold people 10 of the short bolts to prevent this problem. It is really better IF you ARE using one of the engine hooks that go under one of the headbolts to use one of the longer bolts. You can order the sets either way, with 10 short bolts, or the kit that says (9 + 1) which has one of the longer bolts.

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