Koyo & Mishimoto Radiator Failures!!! (Legacy Turbo Models)

[asotwavb]

Have mine at my kitchen table now and trying to seal it up Thanks for the info guys! Good to know i am not alone!

[gilbert]

Ya Derek's car didn't have oil in the coolant either. He would have temps come up under load, and then blow out the overflow. He got his coolant tested for hydrocarbons which confirmed the leaking headgasket.

How do we test for Hydrocarbons, is this something that can be done home or must go to a chemical analyst?

I have temperatures shooting up on strenious rides, but is quite ok within the normal daily rides.

All of the Blown Subaru HGs I've seen did not mix coolant & oil, the cars would just fill the overflow bottle up & then overheat.
I thought Nico's car was leaking only @ high (ish) boost- so it would not have the normal symtoms, but now that I hear a few folks have had the same problem in the same location I'd say it may well be a problem with the rad.

I am thinking of any fair and easier way to prove the HG is blown, before I can go into this expensive affair, will first go check the radiator from an expert.
Any mechanic visited tells of the HG is blown and thats the reason for coolant flooding reserve tank and spilling out, while temperatures shoot up.
Any new ideas before I could go this expensive repair.

thanks for all the posts, very helpfull, thats why I do think my radiator could be the culprit though it is stock.

[Legacy777]

How do we test for Hydrocarbons, is this something that can be done home or must go to a chemical analyst?

I have temperatures shooting up on strenious rides, but is quite ok within the normal daily rides.

Here's what I bought.

http://www.tooltopia.com/uview-560000.aspx

[gilbert]

How do we test for Hydrocarbons, is this something that can be done home or must go to a chemical analyst?

I have temperatures shooting up on strenious rides, but is quite ok within the normal daily rides.

Here's what I bought.

http://www.tooltopia.com/uview-560000.aspx

Thanks for this, will try and locate similar locally, or exact that I can
try out before I can do a HG repair job.

[NICO]

you want to hear something else funny so after my 3 koyo rad i said ill get a MISHIMOTO !!

guess what im on my second mishimoto !! the one in my car that is replaced 2months old just started leaking !! now on both sides of the rad !!







passenger side



drivers side

[prodrive]

you want to hear something else funny so after my 3 koyo rad i said ill get a MISHIMOTO !!

guess what im on my second mishimoto !! the one in my car that is replaced 2months old just started leaking !! now on both sides of the rad !!







passenger side



drivers side

mind did same thing!!!!!

[NICO]

^ this is getting out of hand now, im going to get the oem made in japan buy subaru from the dealer.. these aftermarket are just scrap junk

[evolutionmovement]

Well, at least there's a lifetime warranty!

[NICO]

evolutionmovement - ya for real !! i dont know but its not my motor, i switch motor's like girls switch there clothing... its in the stock location, with factory mounts all stock, oem rubbers !

monday 8am ordering me that oem rad lol, wednesday 8am putting it in.

[Legacy777]

Yeah....after doing some homework, I'd recommend sticking with the OEM Subaru radiators....

[NICO]

Legacy777 - ya its just getting out of hand now ! i talked with the main guy and they are going to look into this problem and do a r&d on our rad because there is way to many people with broken rad's

you should see what is going on with the mustang guys they have just bad reviews that they are making them new ones total from scratch with a new design !

Legacy777 can you change the topic of the post to koyo & mishimoto radiator failures.... i want people to know what they are getting into if they decide to think of getting one of these brand rads !

[subaru_styles]

its kinda a double edged sword as I have gone through 2 or 3 OEM rads. by having leaks/ hairline fractures in the plastic end tanks

[bmxpunk]

This will sound awful but I dribbled jb weld down where the tank mets the fins and haven't had a problem since. It's not perfect but it will do until I find a suitable replacement.

And since my Carr is strictly a rally car now, I want to look at a custom radiator and Fmic setup.

[Legacy777]

Legacy777 - ya its just getting out of hand now ! i talked with the main guy and they are going to look into this problem and do a r&d on our rad because there is way to many people with broken rad's

you should see what is going on with the mustang guys they have just bad reviews that they are making them new ones total from scratch with a new design !

Legacy777 can you change the topic of the post to koyo & mishimoto radiator failures.... i want people to know what they are getting into if they decide to think of getting one of these brand rads !

Nico,

I changed the thread title.

[evolutionmovement]

Has anyone tried plastic welding the OEM radiators with cracked end tanks? I don't know what kind of plastic they use and if it's weldable, but if so, it may be able to repair them cheaply and more easily than the aftermarket aluminum. If it is a weldable thermoplastic, you might even be able to reinforce the common failure points with a bead of weld before it cracks in the first place.

[NICO]

^^ I just got a new one lets see how long this last, I got 3broke Rads laying around I should send you one and you can try with these aftermarket ones

Legacy777 thank you very much

[Legacy777]

From my experience on my n/a radiator the plastic end caps fail at the top front on the passenger side. I would assume they fail because of the heat pressure cycling from the high temp coolant coming from the engine.

Due to the heat fatigue I don't think any kind of thermo plastic welding would work.

[evolutionmovement]

Yeah, that makes sense as brittle plastic will just break elsewhere, but I still wonder if a new unit could be reinforced if the break is at a stress point, say a flange or something where it meets the aluminum section. Of course, if it's just in the middle of a flat, then there's not much you could do. It's too bad they don't make the performance radiators in brass as brazed brass would probably be the strongest (also the heaviest and, possibly, too physically large as a double row).

[Legacy777]

From my experience, it cracks in the middle of the plastic, which in my mind is an indication of heat & pressure fatigue. Making the material thicker might improve the fatigue resistance, but not sure you'd be able to do anything to it as an "aftermarket" fix.

[evolutionmovement]

Yeah, that sounds pretty bogus then.

[ciper]

FWIW I had two OE NA radiators fail in the same place as Legacy777

[SiCkSTi04]

FWIW I had two OE NA radiators fail in the same place as Legacy777

What were the mileage on those when they failed?

[ciper]

I'd guess 150k and 200k

[Legacy777]

That's probably around when mine failed. But that seems to be longer than what Nico is getting on the Koyo or Mishimoto radiators.

[NICO]

if my oem rad last 150 to 200k i'm more then happy, it will out last the motor lol !! these big bad super rad's last 3 months and they pop.