Water Jacket Corrosion

[Martin Law]

Hey all,

I had my Zen water jacket cap off the other day and noticed that quite a bit of corrosion had developed on the aluminum cylinder case which is inevitable. I know it would only take a small piece of that corrosion to break off and plug the outlet water fitting possibly resulting in a complete meltdown.

Has anyone come up with a way to stop or reduce this age old phenomenon?
I know guys that remove the cap and clean the water jacket at the end of each running day but it seems there has to be a better way.
Your thoughts?

Thanks,

Marty

 

[FloridaScaleBoater]

Hey all,

I had my Zen water jacket cap off the other day and noticed that quite a bit of corrosion had developed on the aluminum cylinder case which is inevitable. I know it would only take a small piece of that corrosion to break off and plug the outlet water fitting possibly resulting in a complete meltdown.

Has anyone come up with a way to stop or reduce this phenomenon?
I know guys that remove the cap and clean the water jacket at the end of each running day but it seems there has to be a better way.
Your thoughts?

Thanks,

Marty

I backflush my cooling systems with my pickling oil, both nitro and gas engines, from the outlet on the side of my boat until it comes out of my rudder.
My pickling of choice right now is marine engine store/fogging oil.

 

[Steve White]

Back-flush is the answer. I use WD-40 as it clears out quickly and gets the job done.

 

[Martin Law]

I've read in previous posts that any fluid used that is mineral based has a tendency to swell the seals and soften the water line tubing.
Any of you guys that use that method have that experience? Seems like a reasonable process.

Thanks

 

[Hydro Junkie]

Bondrite 1132 Alodine chemical conversion coating. This stuff is used in aviation to prevent corrosion of aluminum. The drawback is it's not cheap at $194 for a "touch up" pen, plus shipping. It is easy to use, just like using a hiliter on a bare aluminum surface, just don't touch it until it's totally dry since it is corrosive. Once it's dry, you probably won't ever need to recoat, that is unless you scratch through the coating. You can get it through Aircraft Spruce:
https://www.aircraftspruce.com/catalog/cspages/touchprep.php

 

[K F Wheeler]

Alcohol. Think it was Stu that said that... Doesn't swell the rubber O rings.

Ken

 

[John Beardslee]

I pump Corrosion X through all water jackets as part of my after run. You can use WD40 but you will need to flush it out after with something that won’t attach the o-rings. ie: alcohol, Sta-bil fogging spray, Corrosion X etc.

 

[john v]

I also use wd40 for the water jackets, never had the black orings swell but my cmb 90 with the orange orings would definitely swell

 

[Kristy Wallace]

Fogger

 

[Gary Parker]

I am not sure if this would be applicable to your racing rigs but I treat my 26cc engines (that I run in salt water) the same as my full size outboard motors. After use I attach the home garden hose to the water inlets with an adapter I made, start the motor and run for it five minutes to completely flush all the jackets and system.
I expect the pond water you run in is fresh but it would be not be filtered anywhere near as well as your domestic water supply.

 

[john v]

Oh yeah, if you run your zenoah in salt water, flush the cooling jacket and the entire boat with soapy water to get the salt off and then run wd or something in the water jacket, salt Water will destroy that motor if not flushed

 

[DON MAHER]

Jack the man behind J&G motors gave me this tip meany years ago works great and every gas boater has it!
Just pump your gas through the cooling system to remove the water and then gently blow out the excess gas leaving a
Coating of oil in the cap! Been doing this for years and there is never any corrosion!

 

[Martin Law]

Hmmm...2 stroke gas? Seems easy enough...

I do use Klotz Super Tech so I think since it is a synthetic oil that would be okay but what about the 20% castor oil that is also in it? Since that is a plant based oil would that not attack the seals and rubber water tubing?

 

[Daniel's Racing]

Hmmm...2 stroke gas? Seems easy enough...

I do use Klotz Super Tech so I think since it is a synthetic oil that would be okay but what about the 20% castor oil that is also in it? Since that is a plant based oil would that not attack the seals and rubber water tubing?

It won't hurt the cap orings any as they seem to be fine with petroleum based getting to them. The castor goes through the engine and all it's seals so cap orings should be fine as well. The little soft one at the top seams like silicone but I don't think it is as I have never seen fuel/oil attack them.

Petroleum based is what attacks silicone hoses. Synthetic i still petroleum based. The castor may too I don't know but the oil and the fuel for sure will.

Be sure to flush it well on any fast boat as most anything you use will attack the silicone and make it slippery as heck and easy to blow off your fittings.

 

[DON MAHER]

I don’t use castor in my application, so I don’t know. Maybe try it out and see if it works or not!