Water Coolant Gallery Painting for corrosion prevention?
 

https://cimg2.ibsrv.net/gimg/www.rx7...e205b7cc42.jpg

Can we do the same thing here? The green color for the coolant gallery for the rotor housings and the front, mid and rear steel plate coolant galleries?

For preventing rust after bead blasting? yes we can use glycol coolant to prevent rust but I was thinking of another protection aside from using the coolant itself

Will the paint affect the cooling capability of the engine? due to the paint preventing direct contact to the metal of the coolant/water?

Thanks, Ive searched a lot and to no avail

no

paint hurts the thermal conductivity that the cooling system needs

it also won't stay put, instead shed off into the cooling system and clog up stuff or wreck your water pump seal

aluminum doesn't corrode if you change your coolant regularly and use distilled water instead of hard tap water

the housings rot due to acidic(very old coolant) or mineral deposits(hard water) in your cooling system, causing electrolysis to occur. avoid that and you will not have an issue.

Thanks :)

I've heard the opposite re: distilled vs. tap water. The theory being that tap water is already full of impurities, so the water is less likely to attack the metal.

Either way, if you start with a clean engine, use good coolant, and change it regularly, you won't have any issues. I use 2 gallons coolant to one gallon water, this brings the boiling point up and helps combat localized boiling near the spark plugs. And two bottles of Water Wetter per engine. I think I don't have any room for water in the cooling system with all that :)

I pulled apart a bunch of engines this winter/spring and a common theme among them was that they all seem to have been run with only water, no coolant. Rusting and corrosion out the wazoo. (I should be able to save the TWO that i got with good chrome) Also, judging by the side housing wear, air filters were also considered optional. :nono:

Anybody want any tallport 12A side housings that desperately need lapping? I have a bunch now and I don't have the heart to scrap them and I can't afford to save 'em...

you can retest my results and prove me wrong, if you wish.

Theory is always theory, practice is practice. I've never had corrosion issues with tap water.

If one wanted to be really anal-retentive, one wouldn't use water at all and buy pre-mixed coolant. It's more expensive but you get the benefit of, in theory, using coolant that was engineered to work with whatever water it is mixed with.

I have heard that a lot of the reason different manufacturing centers (Japan, Korea, Germany) specifiy such wildly different coolant chemistries is because they are tailored to the kind of water that is normally found there.

I will allow that, of all of the OEM systems I have worked with, anything with Toyota pink coolant or BMW blue is generally immaculate no matter how old it is. And those two seem to last forever. If I were starting fresh everything, I'd use one of those. As it is, the coolant you use will leave a protective layer of "stuff" on the various surfaces, and if you change coolant species, the new coolant will leave its own layer of "stuff", so once you choose your poison you really should stick to it.

New 12A car is getting its engine's coolant passages bead blasted, and the radiator will either be boiled out or replaced if I can find a decent copper-brass radiator (rules specify radiator must not weigh less than stock, so no aluminum allowed), so I may run Toyota coolant in that car.

I think we can all agree, no one is volunteering for VW jello, I mean, G12.

you shouldn't trust anything but your own eyes. back in the early 2000's chevrolet had this thing called Dex-cool, you can still find it today, however it has no place in any engine. we were pulling it out of the cars because it was killing water pumps, intake manifolds and gaskets. engineering always has flaws.

I'd hate to have any paint chips fly loose and clog up the rad.

Dexcool is fine as long as it doesn't get aerated, or oil in it.

When the intake gaskets would fail because they were a crappy design (Ford used the same kind of gaskets and their own coolant. Ford also had intake gasket problems, and on the 4.2 this will bend rods because they leak into the engine and cylinder number 4's intake port) then the coolant runs low, gets aerated, gets oil mixed in, you get mud.

Keep the system leak free, and on cars with expansion tanks instead of overflow tanks, the coolant is a non-issue. I did intake gaskets on a new-series 3.5 (I'd like to say '09 Impala) recently, for example, the OE coolant was fine. Because, I did the gaskets for an oil leak, no coolant goes through the intake manifold on the redesign, and the cooling system was still airtight and intact. There was a minor amount of gunk in the overflow tank because that is the point where the coolant can mix with air.

actually not one piece of that information is true. try again.

keep in mind i was seeing those cars/issues daily back when i worked for cadillac/GM, most of them were only a couple of years old at that point(virtually new still). i actually saw some people try running the stuff in rotary engines too, funny how they were leaking both internally and externally too.


since you are running heavy on the coolant versus water you probably won't notice hard water issues, it is more of a 50% and higher ratio of water to coolant and even then still takes some time.

Which part isn't true, the Fords having intake gasket issues, the coolant not being a problem on engines that don't leak and have expansion tanks, or what?

Because a large percentage of the cars we service are GMs and Dexcool has not proven to be a problem on a properly maintained vehicle. Millions of Ecotecs on the road with the original coolant and never an issue, because they have expansion tanks and they stay watertight.

I've also done a few 4.2 engines for the coolant leaking issue. There's even a TSB for "engine knock" because the intake sucked just enough coolant to hydrolock it and shorten #4 rod so the piston whacks the crankshaft at BDC. No Dexcool involved, just the Ford green coolant whose part number I forget offhand.

The problem is that the plastic frets over time and breaks the O-ring away. The 60 degree V6 has even more of an issue because the acute angle of the intake manifold means there is a lot of vertical motion as the engine expands and contracts with every heat cycle, and when the gasket starts leaking, there is a large dead area around cylinder #1 where a permanent air pocket forms. And on the 8mm rocker stud engines, the exhaust valve binds up enough for the pushrod to rip the bolt out of the head. Sometimes happens on #3 as well. The 3.9/3.5 redesign eliminated those problems by going to the coolant manifold across the front of the engine.

Interestingly the 4.6/5.4 had the same kind of gasket, but not the same fretting issues, probably because there is no wedge to the intake flanges. The manifold faces are completely horizontal.

I've been doing this for just a little bit... ;)

I just recently had to help my buddy replace his intake on his 5.4, we were originally going to do intake gaskets (had a choppy cold idle) and replace the crossover orings cause it was leaking. Got it off, took the crossover off, oring lands were broke. Course this truck also has 228K miles on it and those are original

I also helped him change one on his sisters 4.6, same issue, plastic intake cracked

I don't see why companies want to run coolant through plastic, its obvious what will happen

run it in your RX7 and get back to me, also run straight tap water in your engine and get back to me, compared to straight distilled water. tear the engines apart after a season and see the differences.

Have not fight in this, but I too would advise against tap water. The source of it may vary, and have different properties/minerals in it.

Example, Flint Michigan and GM water/lead poisoning.
Flint Water Crisis: A Step-By-Step Look At What Happened : The Two-Way : NPR
GM specifically unhooked from Flint water, because it was corrosive.
Lesson: Not all water is the same, especially tap.
~$1 for a gallon of distilled, that's cheap insurance.

Or if you have a dehumidifier in your home, distilled water is free

I've always run tap water in my engines, never an issue. I do change the coolant more often than "eh, whatever", though. At least once a year I will pull the radiator and wash/rinse the fins to keep efficiency up.

BTW, the 177k CTS that I did timing chains on this week had the original Dexcool in it and the water jackets looked pristine. The timing chains were scary-bad, though, when I was rotating the engine to the service position, the primary timing chain actually bound up, the teeth on the chain were trying to hit the teeth on the crank sprocket! I had to feed the chain onto the crank sprocket by hand until I brought it to position. I'm not a deeply religious person but someone, somwhere, was looking out for this car's owner :eek:

Distilled water does make a difference with the impurities, most coolant systems go untouched unless theres a problem so people dont change coolant as often, hence corrosion, its cheap enuff just use distiled water and and good coolant, another option is the waterless coolant, thats something totally different

apparently the Japanese coolant wants distilled water, and then becomes PH neutral, and is basically then good for quite a lot longer than the service interval.

this also probably does explain the pre-diluted coolants, it takes out the water quality variable.

i know nothing about any of the other coolants, didn't ask, don't care.