REDZn Engine Anodes are now known as PRO Engine Anodes. Available exclusively at


Long Answer Short:

Each REDZn Engine Anode is a complete anode assembly. The plugs are not intended to be reused (see bottom of page if you are stubborn).

Short Answer Long (the myth of reuse):

There are two schools of thought when it comes to reusing engine anode plugs. Few do and most don't. I started out as a reuse guy, but over the years came over to the dark side; finally and reluctantly admitting that it just wasn't worth it. As the designer of REDZn Engine Anodes, my personal experience with the old threaded design is that the great majority of the time there are either broken-off threads from the rod or other residue in the cap that prevents practical reuse in "real-time". I don't ruin my day by attempting to clean-out the old caps and screw in new rods on-site. This experience was gained, the hard way, by replacing anodes on my twin Yanmar 240's and a Kohler genset (15 total zincs). With the traditional, threaded design – now in my rearview mirror - I keep two sets of plugs on hand. One fresh set, loaded with new zinc rods and one installed set waiting to be removed from the engine. After replacement, the spent set comes home for reuse prep. I attempt to unscrew the zinc remnant from the plug but that rarely works. Instead, I break or cut the exposed portion of the used zinc, soak the plugs overnight in muriatic acid and rinse. This dissolves the zinc remnant and leaves the inner plug threads free of debris. Of course, I need to dispose of the acid afterwards. Finally, I replace with new rods. Even then, the new rods don't always thread in smoothly. I've frustratingly broken brand new pencils in the process of installing them into the prepped caps either in an effort to make them tight so they won't un-thread when pulling from the motor next season or because the threads on the plugs were no longer true. Some people take the added step of cleaning/renewing the threads with a tap. Each year I curse myself for wasting time cleaning out the old plugs, but I feel bad about chucking them just because I'm the guilty sort. The yards to which I've spoken say they generally chuck'em, because at 120 bucks per hour it's not worth their time/their customers' money to reuse them. Their primary objective is for the job to go easily. I know that when I'm stretched out in an impossible and painful yoga pose around my engine blindly struggling with a stubborn zinc, I'd gladly pay a buck or two up front to have had it just come out easily the first time and avoid any more costly or time intensive problems. That pain was the genesis of REDZn . When considering the possibility of replaceable rods for REDZn plugs, it ultimately became clear that that solution would cost more than it would save in terms of reliability, simplicity and outright dollars. REDZn single assembly, Rapid Extraction Design is a higher quality, lower total cost solution. Anode replacement goes quickly and smoothly, the mechanic stays in a good mood and makes it home in time for dinner. Ancillary tasks associated with stuck rods – removing end-caps, replacing end-cap gaskets, pulling alternator/pump/etc to get to the end- cap because it's in the way, dropping a bolt in bilge, disturbing a cooler that's in bad shape and now it leaks, etc, etc - are eliminated. Interviews with boat yard mechanics and do it yourselvers indicated no religiousness about reusing plugs- especially if the hassles of anode replacement are addressed. Since I've started using REDZn on my personal boat replacing zincs has become the no stress, straightforward job that it appears to be. I simply unscrew the plug and out comes the zinc. Easy job easy – what a relief. Try REDZn ™. Our patent pending ExtractionAction is pulling for you.

P.S. Instead of muriatic acid, I've heard of drilling out zinc remnants and even melting zinc remnants stuck in the traditional threaded plugs with a blow torch!

P.P.S. I still don't like the idea of throwing the plugs and remnants of the rods into a landfill unnecessarily. The possibility of a recycling program for REDZn is being explored.

I Don't Care - I Want To Re-Use The Plugs Anyway

There is no reason that this won't work. We confirmed this by cutting the rod close to the plug and soaking the plug in a cup of muriatic acid to 'boil' away the remaining zinc (same procedure as we used to use for traditional threaded zincs). We then pressed a new rod in using an inexpensive arbor press (Harbor Freight). A workbench vice, trigger clamps, etc would probably work along with any other method that comes to mind to gently press a new rod back into the plug. REDZn ™ will support you if you would like to re-use your plugs in this manner. Contact us for pricing of replacement rods.