Re: rpm
Bassult.... Your engine overheated for some reason and apparently the warning horn is either non-operational, or has been removed..... or you ignored it or didn't hear it. Overheating will cause the S.L.O.W. feature to engage which knocks out one bank which in turn drops the rpm to approximately 2500 rpm.<br /><br />That drop in rpm is to warn the operator that something is wrong and to shut the engine down. This feature takes place long before the engine is hot enough to do any damage.<br /><br />However, I agree with Rick that you should take a compression reading. If the engine got hot enough to smoke, I would strongly suspect that bolts have lost their torque and gaskets have failed.