Breakdown cover used radweld

[AlexGSi2000]

Friend of mine had a low coolant warning light the other day - he pulled over and topped up, but was evident there was a coolant leak on the car.

Coolant warning appeared again 5 miles down the road, so he stopped and called breakdown cover (no naming but was one of the big two).

They arrived at the car, poured in a bottle of radweld and sent him on his way. He managed to get the 10 miles home, but needless to say the leak was still present.

He's asked me to take a look at the car, turns out there is a large split in the thermostat housing, not too difficult to replace - however I'm slightly worried that breakdown cover decided to use radweld, the split in the plastic is fairly large, so its fairly obvious to me that nothing is going to seal it.

More to the point, the car itself is a 2020 and covered 40,000 miles with quite a high value - I could possibly understand radweld if it was an old shed, but shocked that they did this.

Is there any way to flush out radweld? We are a little worried that it may now cause issues further down the line, have read online that it can restrict flow in smaller coolant passages / heater matrix.

I asked my friend if they warned him about this or offered some kind of disclaimer if they used it - to which they didnt.

[E-bmw]

If they had used K-Seal I would be much more worried.

They used a widely used "get you home" solution to the immediate problem & it is very unlikely that it will cause any long-term issues.

When the housing is fixed, make sure the full coolant is drained and replaced & move on with life.

[paintman]

Drain coolant.
Fix leak.
Flush.
Refill with new coolant.
Stop worrying.

[Tony1963]

I wouldn’t be surprised if most of the Radweld made its way out through the split with all that coolant. I really wouldn’t worry.

[AlexGSi2000]

Well, the plot thickens - K Seal.

Replaced the thermostat housing yesterday evening - couldn't for the life of me get any hot air into the cabin, it wasn't even lukewarm.

As you would imagine, I suspected an air lock somewhere in the system, so bled up as best as I could, drained and refilled a few times to try and flush anything out as best I could (no bleed point, header tank is the highest part of the system).

The engine side of the cooling system seems to be circulating ok, sits stable at 90 degrees, pipes getting hot, thermostat opening, radiator getting warm.etc

Spoke to my friend this morning, he informed me it wasn't radweld they used, but k-seal - I'm suspecting at this moment in time that it may have caused a restriction somewhere.
I've never used it myself, but whilst I was replacing the thermostat housing there was a lot of coppery glitter like material.

I've asked my friend to try and obtain a report from the AA, as I'm thinking if the k-seal has caused other issues then he may need to go down the legal route.

I still cant believe for the life of me that any kind of sealant was used - I was of the opinion it was used as a last ditch attempt if you wanted to try and ilk some more time before a car went to the scrappers - not used on relatively new cars.

Edited by AlexGSi2000 on Wednesday 22 May 09:36

[E-bmw]

AlexGSi2000 said:

I was of the opinion it was used as a last ditch attempt if you wanted to try and ilk some more time before a car went to the scrappers - not used on relatively new cars.

No, it is a get-you-home repair also.

[E-bmw]

AlexGSi2000 said:

Well, the plot thickens - K Seal.

Spoke to my friend this morning, he informed me it wasn't radweld they used, but k-seal - I'm suspecting at this moment in time that it may have caused a restriction somewhere.

It is possible that you have a restriction like you say, there are many areas that could be the problem.

Is there any heat anywhere up the radiator with the situation as it is? The radiator has small tubes which could block.

Is there a small-bore "balance pipe" going from the top of the radiator to the expansion tank? This could be blocked.

Have you tried running the engine with the expansion tank lid off, this can frequently liberate more air out of the system.

What car/engine is it as some do have hidden means/methods of bleeding air out.

[GreenV8S]

AlexGSi2000 said:

couldn't for the life of me get any hot air into the cabin, it wasn't even lukewarm.

Given that the system has been drained, an air lock is vastly more likely than a blockage.

Was the appropriate venting procedure for this vehicle followed after it was refilled?

Edited by GreenV8S on Wednesday 22 May 13:58

[paintman]

GreenV8S said:

AlexGSi2000 said:

couldn't for the life of me get any hot air into the cabin, it wasn't even lukewarm.

Given that the system has been drained, and air lock is vastly more likely than a blockage.

Was the appropriate venting procedure for this vehicle followed after it was refilled?

^^^^^
Some cars are a nightmare. Some even have small extra bleed valves in the hoses & the sequence needs to be followed.

Tell us what the car is & with a bit of luck someone might know.

Edited by paintman on Wednesday 22 May 11:36

[dingg]

K seal won't choke anything other than a pinhole or seep in the cooling system.

You just need to bleed it properly...

[AlexGSi2000]

The heat seems to be gradually coming back, after some light driving - still not as toasty as you would expect though.

The car is a Mercedes CLA200 - using M282 1.3 engine, same unit used in Renault / Dacia.etc

We allowed the car to "self-bleed", run up for 10 mins with the coolant cap off, until the thermostat opened. Tried with the pressure bleeder, but didn't manage to get any more air out of the system, the pipes going to the heater matrix were hot on the flow & return.

[Griffith4ever]

dingg said:

K seal won't choke anything other than a pinhole or seep in the cooling system.

You just need to bleed it properly...

I've had good success using kseal pro on a porous head. Great stuff. A lot of people assume its some kind of evil engine killer.

[GreenV8S]

AlexGSi2000 said:

the pipes going to the heater matrix were hot on the flow & return.

That's a good sign.

If you still don't have warm air, either the air lock is within the heater matrix or the heater itself is faulty.

[ARHarh]

Griffith4ever said:

dingg said:

K seal won't choke anything other than a pinhole or seep in the cooling system.

You just need to bleed it properly...

I've had good success using kseal pro on a porous head. Great stuff. A lot of people assume its some kind of evil engine killer.

Seem to remember Jaguar recommending K seal after a head gasket replacement on the AJ6 engines. Not sure where that comes from and I may be very wrong.

[AlexGSi2000]

I've no doubt people have been successful using K-Seal - I'm not implying its a bad product.

I think the reason I was baffled is to why it was used in this particular application / scenario;

- Massive coolant leak, to the point where something was almost physically detached - nothing was going to seal it.
- The part was a 15 minute swap, a plastic piece on the side of the engine - clearly visible and clearly replaceable.

So why bother trying to use a sealer?

Would have thought the best scenario in this case would be to pop it on a low loader and take to the garage / home.

[E-bmw]

AlexGSi2000 said:

I've no doubt people have been successful using K-Seal - I'm not implying its a bad product.

I think the reason I was baffled is to why it was used in this particular application / scenario;

- Massive coolant leak, to the point where something was almost physically detached - nothing was going to seal it.
- The part was a 15 minute swap, a plastic piece on the side of the engine - clearly visible and clearly replaceable.

So why bother trying to use a sealer?

Would have thought the best scenario in this case would be to pop it on a low loader and take to the garage / home.

Kind of a bit late to argue the point now, perhaps the driver should have pointed this out at the time.

[AlexGSi2000]

E-bmw said:

Kind of a bit late to argue the point now, perhaps the driver should have pointed this out at the time.

True, however the driver doesn't really have an interest anything mechanical - so trusted whatever the breakdown firm were doing.

Of course, if it were one of us, we would have identified it as an easy fix and had the car transported.

[Griffith4ever]

AlexGSi2000 said:

I've no doubt people have been successful using K-Seal - I'm not implying its a bad product.

I think the reason I was baffled is to why it was used in this particular application / scenario;

- Massive coolant leak, to the point where something was almost physically detached - nothing was going to seal it.
- The part was a 15 minute swap, a plastic piece on the side of the engine - clearly visible and clearly replaceable.

So why bother trying to use a sealer?

Would have thought the best scenario in this case would be to pop it on a low loader and take to the garage / home.

Agreed - quite odd. He should have loaded you up and driven you home.