Topic: Corrosion Questions - linked issues or just coincidence?

[ben_jamin]

So I'm bringing my 77 CB550K out of winter hibernation and I've come across a lot of corrosion in places I haven't noticed any previously.  During riding season, I keep the bike on a sidewalk under a bike cover.  During winter months, it is in a garage.

1st:  I've had an ongoing issue with a slow drain on the battery and semi-rapid build of corrosion on the negative terminal of the battery.  I looked everywhere for bad ground connections, cleaned all electrical connections, replaced several connectors behind the left-hand plastic cover and at the ignition switch (with new from Oregon Moto Parts).  I did all the charging system tests listed in the FAQ section and tested the various components (rectifier/regulator/coils, stator, etc) and all checked out ok.  I did all of this last season and the issue still persisted so I just ignored it and used the kick-starter without much issue.

2nd:  I brought a set of carbs on ebay that were in much better shape than mine and bastardized parts from both.  When I took my carbs apart, I found a heavy amount of corrosion inside the #1 float bowl primarily around the main-jet.  This particular float-bowl wasn't sealing great due to stripped out threads on the carb body (thus the need for a new set). Is this just moisture getting into the float bowl due to poor seal?  Or could this be related to something much worse?.

3rd:  When i removed the left-hand crank-case cover, I found more corrosion on the oil-pump.  This is the first time I've seen corrosion at this location in the 7 years I've owned the bike.  I have a spare pump, so no big deal, but I'm just wondering why this happened now.

I attached a couple photos of the oil pump and float bowl.  Could any of the above corrosion issues be related?? 

[iron_worker]

If your battery is constantly draining and you're recharging it or the alternator is struggling to recharge it's possible that the battery is producing excess fumes. I know even the fumes of strong acids will cause corrosion on nearby metals. Just a thought.

If your battery is draining at rest you should unhook the battery ground (with the bike off, key off) and put your multimeter in DC current mode inline between the battery negative and ground cable. If there is current draw with the bike off/key off then you will have to start disconnecting things to find what is drawing that shouldn't be.

I'm not 100% positive this is your problem but it's worth checking I think.

*Edit* Another thought ... if your battery is on the way out and your charging system is struggling to charge it all the time this could have the same effect.

Also check that your battery is vented properly. My bike has a line that runs down to below the swingarm to get fumes away from everything. *edit*

IW