Right Time to Replace Anodes

CDory23

New member
I"ve searched this forum and briefly online to find the right time to replace both the internal and external Anodes on the outboards. A lot of answers seem to be when they show signs of corrosion. I would think the answer would be when you see actual degradation or size reduction from your anodes because its doing its job. Is it true that if its whiteish and has corrosion on the external surface area of it that it needs to be replaced? I would think there is a lot more zinc there, or is it because if its not on the surface area it loses its active factor. I would assume your actually OK until the Anode is actually eaten way, but perhaps I"m wrong and I need to replace.

My Internal Anodes on my Yamahas look like very similar to the ones in this video at the 2 minute mark.

https://www.youtube.com/watch?v=Qc-TboVRy8Q

My exterior Anodes do show signs of wear but look as if they have a lot of life left.
 
You'll know when they are bad, they will be badly pitted and covered in and surrounded by white powder/slime.
I think I may start weighing mine before and after for an accurate reading on what's going on.
Thanks
Roger
 
This is the one of few items that wasn't on my radar when I bought all my maintenance items and replacement parts last week.

My power is an 2003 Yamaha F80. I wouldn't be surprised if the external and internal anodes were all original. Should I just buy them all and replace? Or inspect first?
 
In my thinking, annual, (at least), replacement is cheap insurance. Some places that would not be near soon enough. I know of folks who have had the zincs nearly gone in a couple of months. It depends on where you are, and even may depend on where you are in a certain marina, so basing replacement on the hour meter or calendar could bite in the wallet.

From my Yamaha mechanics, replacement should be based on weight. If the weight is below 50% of the original weight, they get replaced. For some that may be too soon, but again, considering what goes away if the anode is gone, I'll put a few extra bucks on the zincs instead of replacing things like motor parts or through hulls.

Harvey
SleepyC :moon

IMGP6694.thumb.jpg
 
Over the years I've seen numerous threads mentioning replacement of internal anodes & each time I get concerned and scour my engine manual for any mention of such. Nothing!! Only things mentioned are two external anodes & bonding wires. Am I missing something somewhere. My engine is a 2003 Suzuki df70. Any thoughts?
 
I have a 1999 susuki df70 the only anode I have had to replace is one on the lower unit the rest are in good shape. The df70 does not use internal anodes.
 
I just replaced my interior zincs there are 3 zincs in the f-115 yami .Two are by the plugs and one is on the starboard side of engine from back of boat . I replaced 2 of them the one on the starboard side just needed a cleaning 7/8 of new .Since we are in SW Florida the salinity of the water is much greater then up in the PNW. I change mine usually once every 2 years Now the zincs on the engine outside (2) usually last a few years also . The zincs i change every 6-9 months are the ones I put on my trim tabs they do not last more then a year for sure .
My advice take a look and change if needed when pulling out interior zincs make sure you have the rubber gaskets to seal them . Happy boating jim
 
nordicstallion":efiw92ob said:
Over the years I've seen numerous threads mentioning replacement of internal anodes & each time I get concerned and scour my engine manual for any mention of such. Nothing!! Only things mentioned are two external anodes & bonding wires. Am I missing something somewhere. My engine is a 2003 Suzuki df70. Any thoughts?
I have a 2006 DF90 & the service manual and I combed through it yesterday and didn't find any mention of the internal anodes either. However, I asked my mechanic to check those last year and lo and behold, they were badly in need of changing out. So I'm not sure why the service manual doesn't show them? Hmmm....

Vern and Fishingmark, perhaps the DF70 doesn't have any internal anodes but you still might want to check with your mechanic.
 
Jazzmanic":dvx207pb said:
nordicstallion":dvx207pb said:
Over the years I've seen numerous threads mentioning replacement of internal anodes & each time I get concerned and scour my engine manual for any mention of such. Nothing!! Only things mentioned are two external anodes & bonding wires. Am I missing something somewhere. My engine is a 2003 Suzuki df70. Any thoughts?
I have a 2006 DF90 & the service manual and I combed through it yesterday and didn't find any mention of the internal anodes either. However, I asked my mechanic to check those last year and lo and behold, they were badly in need of changing out. So I'm not sure why the service manual doesn't show them? Hmmm....

Vern and Fishingmark, perhaps the DF70 doesn't have any internal anodes but you still might want to check with your mechanic.

OR... (just maybe) your mechanic sold you internal anodes that don't exist. I could see that as being an awesome (although awful) business model - replacing parts that you can't see and that aren't mentioned in the service manual. Does he have kids in college? :wink:
 
Ok, I too would like to know about internal anodes. How about some one post a photo here of what we are looking for. I have the Merc 115 4 Stroke EFI, which I think is pretty close to the same engine as the Yamaha. Colby
 
rogerbum":ghyqmmn9 said:
Jazzmanic":ghyqmmn9 said:
nordicstallion":ghyqmmn9 said:
Over the years I've seen numerous threads mentioning replacement of internal anodes & each time I get concerned and scour my engine manual for any mention of such. Nothing!! Only things mentioned are two external anodes & bonding wires. Am I missing something somewhere. My engine is a 2003 Suzuki df70. Any thoughts?
I have a 2006 DF90 & the service manual and I combed through it yesterday and didn't find any mention of the internal anodes either. However, I asked my mechanic to check those last year and lo and behold, they were badly in need of changing out. So I'm not sure why the service manual doesn't show them? Hmmm....

Vern and Fishingmark, perhaps the DF70 doesn't have any internal anodes but you still might want to check with your mechanic.

OR... (just maybe) your mechanic sold you internal anodes that don't exist. I could see that as being an awesome (although awful) business model - replacing parts that you can't see and that aren't mentioned in the service manual. Does he have kids in college? :wink:

Hmmm, kids in college. Actually he showed me the areas on the engine where the anodes are seated so I'm pretty sure I wasn't just looking at the holes for the spark plugs. :wink (Pretty sure being the operative phrase)

Actually, I thought of the definitive way to make sure this is true. Suzuki Motors have a great resource in engine parts and diagrams, Browns Point Marine Service. Sure enough, when looking at the exploded view, it identifies the aluminum anode in the Cylinder Head. :thup

Browns Point Marine-2006 DF90

And Vern, I'm sure you could look up your engine year and model as well. Here's the link:

Browns Point Marine Service-Outboard Parts Look-up

Hope this helps. Peter
 
I also have Suzukis....twin 50s....and never knew about internal anodes until taking them in for service at a dealer who knows his stuff. The owners manual makes no mention of checking them in maintenance. Mine when pulled were virtually disintegrated (1000 hours).
 
Colby your motor is not like a yamaha it is a mercury engine .if it's the 2007 motor they were based on the 1.7 L . Call up your merc dealer they should know . The mercs that were Yamaha powerheads were earlier models when merc and yamaha were in a mutual agreement yami supplied 4 stroke powerheads merc provided anti corrosion formulas and support for yami.

Almost all new motors have some internal zincs built in to fight corrosion . Jim

Colby nice meeting you at St Johns gathering I was in CC-23 (venture hull) Jim
 
Thanks Jim. Good meeting you there also. I had a great time at the gathering, and still enjoying it with 5 other boats still cruising. I'll have to look into the internal anodes then. I haven't seen anything in the manual, but I know that doesn't have everything. I'm sure they are still fine as the external ones are still doing well. Just fresh water! :-) Colby
 
Thank you Peter, you are truly a wonderful human being!! I did indeed find my motor on the Browns Marine site you brought to my attention. Not only do I see two internal anodes,skillfully hidden & unmentioned in the motor manual,but also found that my motor is a 2004 by the serial numbers. I was supplied with a 2003 motor df70 manual when I bought the boat. Probably not much, if any, difference but good for my piece of mind & I can certainly use all the pieces of my mind I can get!!
 
The discussion in this post is about replacing anodes or zincs.

Just a word of caution. What is being replaced are ANODES. These are not necessarily zincs. They could be magnesium, aluminum or zinc. To make sure you're using the correct metal, one should only buy the motor manufactures ANODES (Honda, Suzuki, etc.) I have bought "zincs" from someone who guaranteed that they were real zinc, not realizing that zinc was the worst metal for salt water. The ones I bought from Honda were lighter at the start.

Read the article on anodes in CDORY23's post above.

Boris
 
Back
Top