Metanium salt water NOT-OK

I've been fishing with my pimped-up-salt-prepped Shimano Metanium for a while now taking on mostly salty bruisers at locally stocked ponds. I was very diligent in rinsing and cleaning up the reel immediately at the pond after every bashing session. At home, the reel was also set to dry indoors for a few days and occasionally in air conditioned rooms for faster drying times.

The Metanium is a very light baitcaster and casts very well without much fuss all day long. Occasionally, it will produce a squeak or 2 and will eventually go away as I've prepared the internals with plenty of corrosion protection grease coating. No complains what so ever really. Until I discover some rust stains on the spool shaft when I was switching spools, at less than 3 months of usage, I had to strip down this Metanium for checks.

Nice red and hot outside. I wonder what colour is it inside.

Apologies for the blurry pic, the insides are plenty green and fresh still.

Pinion support's inner bearing's a little dried up but smooth, new packing of marine grease will do as a barrier from salt water ingestion into the bearing and also the crank case.

Custom cut carbon drags still moist with drag grease, which somewhat reduced the jittery drag behaviour a little bit. Some test still needed for a different sized carbon drag discs.

The insides were in good condition with plenty of grease left as protection. The surprising part is that the outer pinion support bearing's all rusted up real good. This pinion support bearing sits inside of the crank case with the free spool support bearing seated further outside of the crank case covered with the mechanical brake knob cover with rubber seals.

Top left, note the bearing seated inside with plenty of rust stains. Bearing's all jammed up. Top right, pinion support bearing all rusted up while the free spool bearing's stuck too with some rust stains on side of the bearings. This calls for ultrasonic cleaning.

With one round of cleaning done, all grease have been thoroughly removed hence giving me a better picture of the actual rust damage. Lo and behold, both pinion bearing and free spool support bearing's rusted up good inside.

With the seals removed, you can clearly see that both bearing retainer cage have sustained quite a bit of rust damage while the pinion support bearing sustained rust damage on a few of it's balls.

So here's the thing, this reel's been rated by Shimano being 'salt water ok', if I remember correctly the claim which was printed on the catalogue. You can clearly see that both the bearing's a little different in colour assuming that the free spool support bearing's the S A-RB variant while the pinion bearing's the conventional A-RB type. I've also done a simple test on the durability of S A-RB bearings previously and have shown that the S A-RB bearing can withstand serious salt water corrosion.

To understand the extent of this issue, I've also had complains from our local Shimano pro-tester sharing with me about the same issue faced only after one salty session with the same Metanium model. Another buddy of mine only fished fresh water with the Metanium and in under 3 months, the same problem occurred. A customer from a neighbouring country had the same issue within 6 months of fresh water bashing.

I'm keen to find out 2 things. How did the reel ingest water which also caused this rust issue internally?

First, I've never dunked this reel in salt water before and have only rinsed it with fresh water after each bashing session. Secondly, the brake knob side's nicely protected with a rubber seal. My only theory is that the gaps between the frame and crank case cover is pretty much where most water is being ingested into the crank case. Given the fact that the case design has small outlet ports for water to pass through around the base in the event that water do get in. I'm guessing that both while fishing and rinsing after may have contributed to water ingestion and retention within the crank case, more specifically within the 2 bearings that's most exposed to water from the inside.

For water ingestion, my solution was rather simple. I've decided to NOT rinse or flush the entire reel after fishing but to have very low running water pass through only on the spool itself where most salt water gets trapped especially using braided lines. Or if need be, I would remove the spool from the body and rinse only the spool. I would then just wet my hands to wipe off any dirt of salt water around the entire reel body taking care not to have water flowing near the gaps. Toweling dry after that helps too.

With the above regime in place, I've successfully reduce water ingestion into the crank case significantly as I've open up the reel checking for water ingestion and found none after a few session.

The second part which I'm baffled is that Shimano's S A-RB bearings isn't as durable anymore, or maybe this batch of bearing's a lemon? Either way, it's a bit puzzling as to why would the S A-RB bearing succumb to rust in such short periods of time. Shimano? What's up with this?

Rust busted up bearing out of the picture, RP Custom hybrid ceramic bearings in. Pinion bearing's revived after rust removal but a little rough now.

Ready for some action once again.

Casting with this Metanium is now even better with the hybrid ceramic bearings. The only difference is that it's a little louder and a tweak on the brakes+thumb behavior change is needed as the spool spins up to speed very quickly.

Seriously Shimano, what's up with this batch of S A-RB bearings rusting up so easily on an amazing reel like the Metanium?