I've had problems with the zincs
coming loose from their threads.
Also, is there a recommended frequency to change
them?
Hi Jim
I've never seen engine zincs that had come loose in their plugs, in fact it is
usually the opposite, they are too tight to unscrew. I suspect that when
you're zics are screwed into the plugs they are not screwed in tightly enough.
Once I screw a zinc into its plug, I'll usually snug them up using a pair of
pliers with a wrench keeping the plug from turning.
Many times though I'll run into zincs whose threads are not smooth, which
makes them difficult to screw down tight enough. Because of this, I always
clean up the threads by running a thread die down them before I screw them in.
As long as I've gone that far, I'll clean up the threads in the plug with a
thread tap also.
So far, all of the threads that I've run into are standard, coarse US threads,
though there are some metric out there. The taps and dies that are commonly
found in hardware stores and automotive parts places will work; no need for
top-of-the-line, high priced taps and dies. Instead, buy the cheaper ones, for
this purpose, and send the difference in cost to me!
As far as the frequency to change them, do it when they are half gone, just
like shaft zincs. Pull the zinc to inspect it every month, every 3 months or
whatever other time frame that you are comfortable with. As the zinc starts to
wear, shorten your inspection periods. No sense keeping a zinc that is so worn
away that it won't last another month, so monthly is the shortest time frame
that I'd recommend for inspections.
Rudy
Briney Bug, Panama City, Fl
> I've had problems with the zincs
> coming loose from their threads.
> Also, is there a recommended frequency to change
> them?
Hi Jim
I've never seen engine zincs that had come loose in their plugs, in fact it is
usually the opposite, they are too tight to unscrew. I suspect that when
you're zics are screwed into the plugs they are not screwed in tightly enough.
Once I screw a zinc into its plug, I'll usually snug them up using a pair of
pliers with a wrench keeping the plug from turning.
Many times though I'll run into zincs whose threads are not smooth, which
makes them difficult to screw down tight enough. Because of this, I always
clean up the threads by running a thread die down them before I screw them in.
As long as I've gone that far, I'll clean up the threads in the plug with a
thread tap also.
So far, all of the threads that I've run into are standard, coarse US threads,
though there are some metric out there. The taps and dies that are commonly
found in hardware stores and automotive parts places will work; no need for
top-of-the-line, high priced taps and dies. Instead, buy the cheaper ones, for
this purpose, and send the difference in cost to me!
As far as the frequency to change them, do it when they are half gone, just
like shaft zincs. Pull the zinc to inspect it every month, every 3 months or
whatever other time frame that you are comfortable with. As the zinc starts to
wear, shorten your inspection periods. No sense keeping a zinc that is so worn
away that it won't last another month, so monthly is the shortest time frame
that I'd recommend for inspections.
Rudy
Briney Bug, Panama City, Fl
