measure carefully. you want to have the same amount of thread biting into the aluminum housing. if the threaded area is too short you will either lack sufficient gripping power to keep it sealed or strip out the aluminum threads in the housing (dont ask how i know). if you get a bolt that is too long be sure to use washers to get the pressure on the top of the cannister.

you need about two to three times the length of thread with a steel stud in aliminum to match the strength of the steel nut on the steel threads.

you also could buy a bolt that has too long a thread and just cut it off and use it as the stud. this assumes that the threads into the housing and the nut are the same.

proceed with care. the oil pressure is contained by this and if you get it wrong you can ruin the engine in a heartbeat.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.