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Old 07-31-2015, 11:00 AM
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2door 2door is offline
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Join Date: Sep 2008
Location: Littleton, Colorado
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Default Re: Cylinder Stud broken

Lots of good discussion in this thread.

As for fine thread verses course, here's another fly-in-the-pie. I've seen many engines with cylinder studs having course threads on one end and fine on the other. I've had folks say they've never seen this and argue with me about it but regardless, it is a fact.

These engines have fine threads in the case and the course threads on top where those pesky acorn nuts go. What I've seen is a builder will not notice the thread difference and will attempt to thread a stud in, forcing the course threads into the fine threaded case. You can guess the results. Then he tries to put an acorn on the fine threads on the other end of the stud. Same results. Damaged threads, leaking head gasket and the engine won't run worth poopy.

I realize this odd stud issue isn't universal but I've seen enough of them to believe they are a source of trouble. In addition to the use of fine and course threads I've also seen studs of different lengths used in the same engine. Add this to the case threads not being precisely the same depth and you have the potential for even more head gasket problems.

And get rid of those stupid chrome acorn nuts. Grind the tops off or replace them with hex nuts.

In defense, I've seen some newer engines coming with taller (longer) acorn nuts that will accomodate the stud threads even if they're a little long.

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