greedy53 wrote:vw do not have a tapered thread it's a common mistake to put tapered senders in as it will force open the hole the more you screw the sadder it gets .nearly all cracks from the sender are a result of this little tapered thread being put into a non tapered hole
sorry greedy53 it is a tapered thread as quoted in the bently manual for installing pressure switch "taking care not to damage the tapered thread by using too much force to screw in the switch. the thread acts as a seal."
as it turns out i pulled mine out yesterday a some one has put a parrallel threaded plug in and it has damaged the lower part of the thread.
part of the problem is that the pressure switch has a large hex so poeple will use a large spaner and over tightern it.
as for repairing it you would need to go over size and fit a reducer. it would need to be taped to 1/4 NPTF and use a 1/4 NPTF to 1/8 NPTF reducer.
A simple rule of thumb for installing tapered
pipe threads, both metal and plastic, is finger tight plus one to two turns with a wrench. Torque installation values
can be determined per application, but due to the variations involved in pipe joints such as disimiliar materials of
male and female threads, type of sealants used, and internal variations in product wall thickness, a standard torque
specification cannot be generically applied .
and a good sealant always helps.
hope this helps.