10 replies to this topic

[luvin_the_rings]

Has anybody ever used 50/50 blend of Muriatic Acid (pool supply PH adjuster, HCl) and water to clean the hard water deposits out of the radiator?

 

We've been trying vinegar, rad flush, CLR, Baking soda and Water, all with no avail.  We have the radiator un-installed and the solutions are jus sitting in there.  Maybe running the car with the heat and flow of the engine/water pump would help.  

 

We didn't clean the overflow tank on the donor car before we ran the season and now our car is overheating from a clogged radiator.  Radiator manufactuer's warranty doesnt cover internal corrosion, or else we would have just picked up a new Radiator. Trying to save a buck by un-clogging this one before we shell out the coin for a new radiator.  

 

Do you think this would be ok to flush the engine with for a few minutes or am I asking for disaster?   

 

-Z

[Alberto]

I personally have not.  I dropped it off at the local radiator shop and they cleaned it up and pressure tested it for a fair price ($20-30 ish).

[Bench Racer]

Chances are if you radiator is crud deposits, so is your block and head.

[Jim Drago]

I would be careful with muraitic acid, you could go right through it

Jim

[Tom Sager]

Don't know about that acid, but vinegar can work well but it is a long process.  You might have to leave it in the radiator for 2 weeks.

[luvin_the_rings]

I am also worried about the block and head, however the head is a new drago head put on only two months ago.  When we put the head on, we did the water pump also, and when looking in the block, didn't see much deposits.  The engine was clean inside when we did a full seal job a year ago.  I think this is just from the engine sucking in the crud from the overflow tank for a few race weekends.  

 

Can I put like 75% vinegar, and 20% water and drive it around a bit for  a week? anybody know if the vinegar is gonna break down my OEM head gasket?

 

I'll look into a radiator shop that can maybe help out. 

 

-Z

[Tom Sager]

It seems unlikely to me that even some residual crud from the overflow tank would be sufficient to clog a radiator to the point of overheating.  How old is the radiator and what type?  Water passages in the engine are much larger than veins in a radiator so it's hard to fathom that you have much trapped in the engine.  If the radiator is truly plugged it might be best to get a new radiator.  Not trying to spend your money but you want to protect your investment in the engine obviously.  A radiator shop would be able to flow test a radiator and would have a proven method of cleaning it but you might end up spending money there only to learn that the radiator is junk.  New radiator plus flushing the engine might be shortest path to knowing everything is right.  

[Bench Racer]

After thought, are the radiator fins clean externally? A guy from St Louis with an F production car had overheating issues with a wide Koyo radiator, the external fins were blocked. Cleaned and life was good.

[luvin_the_rings]

Thanks for the responses guys, 

 

I'll check the radiator externally for blocked fins, but the Radiator is only a year old and has only seen a season of racing, mostly HPDE and Super School.  

 

Its a triple core Mishimoto with some of the skinniest cores I've ever seen. The overflow tank was very very very dirty.  We only noticed this once the coolant turned grey.  Large marble size chunks of sh*t were in there an i'm convinced this is where the crud came from since the car wasn't overheating for almost the whole year and had fresh coolant at the beginning.  Then once we checked the coolant and saw how dirty it was we flushed it and one lap later it was the same grey color.  Then we cleaned the overflow tank to pristine, flushed the engine and rad with hose/distilled water, re-assembled, and found the same overheating issue, and the same color water.  When inspecting the inside of the radiator, I can see the blockages on the entrances to the cores.  

 

Was using distilled and Water Wetter all the time. 

 

We are gonna take it to a rad shop and see what they can do.  I'm hoping they can give us a before/after flow figure.

 

Don't mind picking up a new radiator.  Maybe one that has slightly larger cores to prevent this in the future?  Haven't had any issues with Mishimoto products or customer service so we're gonna go that route again.  

 

Can I just flush with hose water and re-assemble? Or has anybody had any specific good results with another particular radiator flush brand?

 

-Z

[Argus48]

The chemical is too dangerous to use. 

[luvin_the_rings]

Muriatic acid didn't do anything to get the hard water chunks out of the radiator.  Even took the radiator to a shop to have it cleaned, no luck.  

 

Had to replace the radiator.  

 

-Z