3rd F*#king radiator failure getting pissed

[Mick]

Need help guys,

I have just had a 3rd aluminium radiator fail. I have used every additive plus a fitted an Interject stray current arrester. Obviously an electrical issue any suggestions on finding or sloving the problem. Not sure if a copper core radiator will eliminate the problem. How do find the sourct of stray current.

Mick

 

[Mike Pass]

What exactly is the type of failure? The usual cause is the radiator being subjected to flex forces because it is mounted too rigidly. The solution is to mount it so that it is very softly held in very soft rubber bushes. because alloy rads are glued together they are very prone to the joint splitting compared to copper which are soldered or brazed. I doubt that failure would be due to electrolytic corrosion.
Cheers
Mike

 

[Mick]

Thanks Mike it is one thing I didnt consider, although the radiator does sit on the floor located by a centre pin into a rubber grommet, side are clamped and supported using two lugs fitted into rubber grommets in each clamp. it may be there is enogh flex in the front end to bend radiator. I will check the radiator for teltale signs of electrolisis in the day light.

Mick

 

[Phil]

Mick:
It sounds like your mounting is flexible enough, although some photos of the setup would be helpful. I would also check the connections between the radiator and the water lines, as some of the rigid tubing used can limit radiator flex and short connections between the tubes and radiator snouts can be rather inflexible and limit flex or induce stresses of its own. I would bet some photos and more detail would get you an answer here on the forum.
Cheers
Phil

 

[Mick]

Hey Phil
Dont have any solid fixings direct to the radiator, however i will post photos tonight.

 

[Pete McCluskey.]

Mick, my guess would be electrolysis given the way you have it mounted.
An easy and inexpensive test by any half decent sparkie would pick up any residual current.
Another thought and a long shot, maybe one of the additives you are using is not compatible with the glues used to stick the rad together.

 

[JohnC]

Mick, if you're fairly sure you've got a corrosion issue, and it's not mechanical failure, here's a quick test you can run if you have access to a DVM (digital voltmeter):

With the car cool and not running, remove the radiator cap.

Set the DVM to measure DC volts or millivolts. Connect the negative lead to the battery, and immerse the positive lead in the radiator coolant, but don't allow it to touch the metal of the radiator.

Generally, any voltage that you read is not good, but if it's above 0.25 or 0.30 volts, then you have an electrolysis issue which will eat away your aluminum radiator.

If you have a high reading, start pulling fuses and recheck your reading after each fuse is pulled. If/when the reading drops, you have a problem on that circuit - find the device that has a leakage to earth.

If none of the fuses produce a drop in voltage, then disconnect the positive leads from the alternator and/or the starter - these are also known culprits.

Also make sure you're not using any part of the radiator or its shroud as an electrical ground for any accessories, ie electric fans, etc.

 

[Pete McCluskey.]

What good advice Cribbj I will check my car tomorrow.
Mick if you need a Digital voltmeter I have a spare one.

 

[Mick]

I have a renewed faith in our Australian comapnies & manufacturers integrity.

PWR a well known Australian manufacturer of alumininium radiators and specialized racing components have inspected my radiator and could not find any sign of electrolosis.

The manager called me personally to discussed what might be causing the problem, I was expecting a negative response and hand washing of any responsibily. To my surprise he has agreed to supply a new radiator at no charge adding additional structural support to reduce possible flexing. The company obviously investigated the problem throughly and saw no reason for any failure that could be explained.

They have agreed to carry out a visual inspection after it is reinstalled to help ID any potential future problem.

Excellent support from an ethical company.

 

[JohnC]

Glad to hear things are looking up for you and your radiator problems.

PWR get high marks on this side of the pond too. IMO, they build great cooling systems (radiators, intercoolers) and stand behind their work.

I just wish they were a little closer to us here in the USA. Over here they work through a network of dealers and reps, some of whom just don't measure up to the parent company they're representing.

 

[Mick]

John not sure but why dont you order direct, if thats not an options there are anumber of us in Brisvegas including Pete & myself that could arrange any purchase for you and send it via UPS.

Mick

 

[JohnC]

Thx Mick, that's very kind of you to offer. I've had one of their units in a turbocharged Japanese rice rocket that I own, and like it a lot. It's been in there nearly 9 years now, and not a moment's trouble with it. Ally radiators have received a lot of unjust criticism, but if you keep your coolant clean & maintained, they work just fine and give great service.

I was considering getting PWR to make one for my other car, which is one of those red Italian toys from Maranello, but I want this radiator to be larger, and higher capacity, and with a few changes/options the OEM unit doesn't have, so all that would be difficult to coordinate with PWR, considering the distance.

Here in the US we have a very high quality radiator supplier called Ron Davis Radiators, and I'll probably go ahead & source this new unit from them, even though I'll probably have to drive/ship the car 1250 miles to them to get the optimum result!

 

[Jim Dewar]

I had the same FIREDRILL as you several years ago. I had steam pockets causing the core to fail at epoxy seams connecting the tanks. Ruined 2 radiators before I discovered the problem. I often observed the temp. gauge swinging but never read in the danger zone, so I thought when I'm ready I'll replace the thermostat. I replaced the thermostat 2 times and the same problem + another radiator. My Bleed lines from the rear of the intake manifold that were to prevent trapped steam had a tiny piece of teflon tape blocking the flow causing steam to enter the radiator, damaged the core but cooled enough to not appear to be a serious/urgent threat (yes, I also just knew it was stray current). I corrected the coolant bypass flow and its been flawless for 17k miles. I hope some part of my experience leads you a solution.

 

[Mick]

Jim PWR suggested that the raidiators would take much higher pressure that they are generally subject to assuming you dont have massive overheating problems. I had no problem with fluctuation or air pockets. Problem seemed to develop after 2000 miles of good driving so they ruled out pressure as a cause.