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Coolant tank... Learn from my mistakes

N

neonshaun

Experienced Member
Joined
28 May 2011
Messages
267
Location
sf bay area
Just over a year ago, my original coolant tank finally went out and started spewing out of the seams.
So I thought... damn... that lasted a long ass time. I'll just get another OEM one and it will go another 20 years.

Well, here I am, just out of the warranty period 14 months later. This one split in 3 places, one on each corner. What junk. Maybe the coolant tank stock is all old stuff.

So for anyone out there who thinks getting another OEM plastic tank is a good idea, don't waste $110 bucks like I just did. Just get a metal one and be done with it.



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jwmelvin said:
That's unfortunate. Kaz has been reporting the same thing about the tanks recently. Hope the next one lasts.
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I was about to change mine. It isn't leaking, but very discoloured It has 54k miles and is 26 years old. New one in the box waiting for me to change all the hoses this winter.
Hmm, what to do?


Sent from my iPhone using Tapatalk
 
Ten years ago I replaced my seeping OEM tank with an aluminum one from SOS - with sight tube. (I also did all the car's hoses at the same time.) That would be MY recommendation.
 
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I had an older style SoS tank that started to leak from one of the seams. Chris Wilson stepped-up and helped me out when I purchased a new tank from SoS. Quality is great, and I purchased the one with the sight tube. Highly recommend checking on this option.

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The plastic tanks leaking at the seam should be an easy fix with a 3M sealant or a plastic welding kit. With those metal tanks the only failure to look forward to is the sight tube getting brittle from the trapped heat of the engine bay.
 
texmorales said:
They dont come black. Looks to have been painted to prevent UV damage from sun. He took the proper precautions but unfortunately got unlucky.
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I don't believe this to be true. The "proper" precaution is to run the JDM NSX-R OEM Black Silicone Coolant Tank Cover. This cover is what ends up absorbing the UV light, heat and damage and not the tank itself. Since silicone is an excellent insulator, very little UV and heat actually transfer to the tank from the sun. Unless the paint he used was specifically rated against UV light and thermal rejection (which I doubt), then you're actually only speeding up the deteriation process by painting it black since black traps in heat.

Just to be clear on this, [MENTION=25691]neonshaun[/MENTION]. Do you have the stock engine cover in place to protect the coolant tank from the UV radiation? Or did you remove it to show your engine?

I believe the UV and heat radiation is what is causing the tank to break apart. My advice to to do this properly next time, is:
1) buy the OEM tank
2) get the silicone NSX-R coolant tank cover
3) run the OEM Engine cover (or NSX-R cover)
4) if you don't run the OEM engine cover, tint the rear engine glass so that it blocks out all UV-A and UV-B light. 3M Crystalline is a basically clear window tint that is basically clear, protects from UV light, and has a high thermal rejection.
 
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for those with tank issues, are you running without the engine cover? has anybody had this failure while running the cover?
 
Hapa88 said:
I don't believe this to be true. The "proper" precaution is to run the JDM NSX-R OEM Black Silicone Coolant Tank Cover. This cover is what ends up absorbing the UV light, heat and damage and not the tank itself. Since silicone is an excellent insulator, very little UV and heat actually transfer to the tank from the sun. Unless the paint he used was specifically rated against UV light and thermal rejection (which I doubt), then you're actually only speeding up the deteriation process by painting it black since black traps in heat.

Just to be clear on this, @neonshaun. Do you have the stock engine cover in place to protect the coolant tank from the UV radiation? Or did you remove it to show your engine?

I believe the UV and heat radiation is what is causing the tank to break apart. My advice to to do this properly next time, is:
1) buy the OEM tank
2) get the silicone NSX-R coolant tank cover
3) run the OEM Engine cover (or NSX-R cover)
4) if you don't run the OEM engine cover, tint the rear engine glass so that it blocks out all UV-A and UV-B light. 3M Crystalline is a basically clear window tint that is basically clear, protects from UV light, and has a high thermal rejection.
Click to expand...

Why would you doubt people didn't take the proper steps? For example, I painted my tank black so I don't have to look at a cheap plastic tank which sticks out like a sore thumb, which the $200+ silicone NSX-R cover doesn't even cover the whole tank! I then did a UV clear coat on top of that. Cheap and easy DIY project. If you want to take the next step and provide UV protection to the entire engine bay and the interior of your vehicle, then you should add a product like the 3M Crystalline, which I did as well.

I think it is perfectly plausible he got unlucky with a "new old stock" tank that was brittle already. If you paint it correctly then there is no reason to spend money on expensive tanks or expensive covers.
 
texmorales said:
Why would you doubt people didn't take the proper steps? For example, I painted my tank black so I don't have to look at a cheap plastic tank which sticks out like a sore thumb, which the $200+ silicone NSX-R cover doesn't even cover the whole tank! I then did a UV clear coat on top of that. Cheap and easy DIY project. If you want to take the next step and provide UV protection to the entire engine bay and the interior of your vehicle, then you should add a product like the 3M Crystalline, which I did as well.

I think it is perfectly plausible he got unlucky with a "new old stock" tank that was brittle already. If you paint it correctly then there is no reason to spend money on expensive tanks or expensive covers.
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While I do agree that it's perfectly plausible that he purchased "new old stock", I still disagree that painting a tank is the proper steps.
Based on the number of failures being reported when the engine cover is removed, I don't think Honda ever intended on owners removing the engine cover. Removing the engine cover subjects the components to additional heat and UV light as we've already stated.

As I stated before painting the cover, even if you use a UV protectant paint, still leaves the issue with heat retention. The original white color reflects light (thereby rejecting heat), the new black color now absorbs light and heat. Basic thermodynamics. You've addressed the UV with the paint and tint, but you may have made the heat issue worse by choosing dark color.

The NSXR silicone cover was probably created to address the additional UV light and heat issue because the NSX-R cover has a mesh design. The silicone is black and would absorb heat, but remember that silicone is a great insulator (you know, like those new style silicone oven mits?) and a much better one than paint.

Finally, we need to make sure we use the proper paint, as may of the components of paint have additives and solvents that could damage the plastic or the sealants used in the tank thereby weaking it even further.
 
I know it's not help but I have had my Stmpo tank for over 5 years and no issues. It's welded aluminum with no site. I check my coolant once in a while.

I would be cautious running one with a site tank since they do have issues from my understandings.

I heard some of the best ones were the old Dali round tanks.
 
Hapa88 said:
While I do agree that it's perfectly plausible that he purchased "new old stock", I still disagree that painting a tank is the proper steps.
Based on the number of failures being reported when the engine cover is removed, I don't think Honda ever intended on owners removing the engine cover. Removing the engine cover subjects the components to additional heat and UV light as we've already stated.

As I stated before painting the cover, even if you use a UV protectant paint, still leaves the issue with heat retention. The original white color reflects light (thereby rejecting heat), the new black color now absorbs light and heat. Basic thermodynamics. You've addressed the UV with the paint and tint, but you may have made the heat issue worse by choosing dark color.

The NSXR silicone cover was probably created to address the additional UV light and heat issue because the NSX-R cover has a mesh design. The silicone is black and would absorb heat, but remember that silicone is a great insulator (you know, like those new style silicone oven mits?) and a much better one than paint.

Finally, we need to make sure we use the proper paint, as may of the components of paint have additives and solvents that could damage the plastic or the sealants used in the tank thereby weaking it even further.
Click to expand...



3 coats of plasti dip is a thick amount of rubber. I doubt it has stuff in it that could damage the paint as I can just peel it off by hand. It doesn't completely adhere.
You think sitting in the sun will get it hotter than an engine compartment of a car racing around a track? Coolant gets to 200+ degrees Fahrenheit. It was built to withstand that...

My real point is that I'm worried a lot of the remaining parts for these cars will be new old stock. So it's better to replace things like this with a permanent metal solution if you can.
 
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neonshaun said:
3 coats of plasti dip is a thick amount of rubber. I doubt it has stuff in it that could damage the paint as I can just peel it off by hand. It doesn't completely adhere.
You think sitting in the sun will get it hotter than an engine compartment of a car racing around a track? Coolant gets to 200+ degrees Fahrenheit. It was built to withstand that...

My real point is that I'm worried a lot of the remaining parts for these cars will be new old stock. So it's better to replace things like this with a permanent metal solution if you can.
Click to expand...
[MENTION=25691]neonshaun[/MENTION] So did you have the engine cover on or not? Just wanted to get that point of reference.

Also, take a look at this blog article about the internal design of the OEM tank. While I agree a metal one seems like a good replacement, I've also heard problems of them cracking at the welds. Also I'm not sure about their inside design. This article makes a good case for keeping one with an OEM like design due to the numerous expansion chambers.
http://www.nsxcb.co.uk/entry.php?1321-OEM-Coolant-Header-Tank
HeaderTank02.jpg

Lastly, the coolant tank was designed to take on the additional heat from the coolant on the inside of it. If Honda felt that painting it would solve the problem, don't you think they would do that instead of creating a silicone cover (which is way more expensive and heavier)? It just doesn't add up. Also remember that in the case the engine cover is missing, the sunlight hits the coolant tank from one side (the rear) since the front is blocked by the firewall. That would create a temperature gradient across the tank which could also influence premature failure. I'm just speculating though...
 
After looking at your photos I was like, "Hey, he stole my NSX!!!!".

I dipped my tank too and left the same viewing port you did. Crazy!!
 
send pic to SOS...3 years is weak...
 
SOS says either I send it back to be repaired and have a few weeks down time, or buy a new tank at a discount. Also said there might be something else wrong like a clogged bleed hose that could be pressurizing the tank.

The bleed hose is clear, any other reason a tank could over pressurize and crack? There's no oil in my coolant, everything seems clear...
 
I'm actually buying a tank this week to prevent any future mishaps.... reading this thread now has me a bit paranoid. :/
 
I don't know what the solution is, and maybe I got a rare bad one from SOS, but when I took the 3 year old one off, I noticed a piece of metal clunking around inside.

For the last few weeks I've been hearing it, and I couldn't figure out where it was coming from! Thought it was an exhaust shield. I guess it's the baffle inside the tank that game loose and was smacking around.

Anyways, I got a new one now, half full of all new type 2 coolant, hopefully this one lasts.
 

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