All tinned radiator tubes, shop credibility...and?

[Extreme-Duty]

Hi,

fourth radiator fix on a 17,000 hour tractor because of cracks and vibration, rather than corrosion and I want something different.

A specialized radiator shop not too far away offered me to customize and recore this copper/steel radiator with a new all in house made core.

The tube-to-header joints are going to be made by dip soldering, which sounds ok to me. What seems more unusual to me is that they are tinning all their copper tubes both outside and inside.

Is it actually common practice to put tin on the inside?

Do you guys see any problems arising from such a large tin coated surface area?

The shop owner is great to talk to, but lost a bit of credibility when he insisted that steel tanks MUST be sprayed with some sort of stainless steel spray to keep them from rotting away on the inside. Eventually I managed to convince him that properly inhibited coolant will do just that. I do not want his foreign particles or ions in my coolant!

Would you allow him to put his hands on your radiator?

Thanks for your comments - ED

 

[Kestas]

Tinning copper for soldering is common practice. Many copper electrical components, like resistor and capacitor leads, are tin coated for easy soldering.

What alarms me is that you mention the radiator is made with copper and steel components. These two metals in the presence of a fluid is a recipe for corrosion. It's no wonder you are fixing it for the fourth time. You are dealing with a corrosion problem, not a vibration and cracking problem.

Stay away from people who talk about using stainless steel sprays.

 

[another Todd]

Can you mount the radiator on anti vibration (or vibration isolation) mounts?

 

[Chris142]

Many commercial rads use steel and copper parts.usually steel tanks on a copper core.

 

[DoiInthanon]

Seems to me you may have corrosion that manifests itself as vibration cracks. See if you can find a radiator cap with a sacrificial anode rather than tinning the inside of the copper tubes.

WRT your second question - Tin is more noble than copper, so it might increase the rate of sacrifice of the steel headers. Perhaps increasing pitting or crevice corrosion -> cracking.

 

[Extreme-Duty]

Thank you for your replies, I appreciate all of them and I am getting closer to make a decision.

Like Chris says, steel/copper combos a fairly common in HD-equipment, so we will have to deal with that.

As for vibration vs. corrosion, the radiator that will be send out to be fixed has a problem that started on the outside: The joint between the upper tank and the right frame rail let go, so the tubes got stressed and stretched to the point where one of them cracked.

No wonder Modine decided to weld the rails to the tanks on the bigger radiators for the CIH Magnum series tractors.

The rad. in question has been sitting in a shed for 6 years, just waiting to be fixed and I am almost surprised how little corrosion there is inside. Caterpillar ELC did a wonderful job!

The rad. currently in the tractor is an exchange part with a cheap and weak aftermarket core. It spend most of its life on Fleetguard ES Optimax (the older nitrated OAT version) and it shows! There is at least some solder discoloration and I cannot deny that this might be the reason for it to leak.

Next coolant is Glysantin G30. Yes, it protects against cavitation with no nitrite and does not have the stupid 2-EH salt found in Texaco made OATs.

Back on topic, the upcoming radiator will be installed with new rubber damper mounts and I am looking for flexible hoses to isolate it from the engine (Cummins 4BT - tough, rough and shaky).

This tractor has seen two more rads. exhibiting little to no corrosion, both of them had to leave because of broken header-to-tank seams, one was a cheap aftermarket POS lasting 3 months!

Long story short, with proper cooling system maintenance, vibration and cracks is the only thing I am afraid of.

So it seems I am still searching for a shop where people can resist spraying things where they don't belong.

ED

 

[HangFire]

Originally Posted By: Extreme-Duty
This tractor has seen two more rads. exhibiting little to no corrosion, both of them had to leave because of broken header-to-tank seams, one was a cheap aftermarket POS lasting 3 months!

Long story short, with proper cooling system maintenance, vibration and cracks is the only thing I am afraid of.

So it seems I am still searching for a shop where people can resist spraying things where they don't belong.


Ed,

Seems to me, if vibration and header-to-tank seams are the real problem, you should look at how the radiator and hoses are mounted and see if you can reduce the effects of vibration on that area that keeps breaking.

 

[Extreme-Duty]

Originally Posted By: HangFire

Ed,

Seems to me, if vibration and header-to-tank seams are the real problem, you should look at how the radiator and hoses are mounted and see if you can reduce the effects of vibration on that area that keeps breaking.


Yes, it was a pain to see it happen twice in about the same spot. I bet part of it is the tank itself as it lacks structural strength. If you squeeze one of the hoses just a bit, the pressure created will lift the top plate by 0.5-1 mm. So fatigue has to be added to the list of flaws.

Hope to have less vibration with flexible hoses. The downside of these things is that they will try to straighten out as system pressure rises and put strain where we did not have it before. Just another challenge with the upper hose being a 2x45 deg. elbow.