[bym007]

My ‘17 540i developed a coolant leak this week, and my Indy found a leak in the radiator. His advise is to replace both radiators, since he is already pulling both out as part of the job and it will not cost me extra in labour. Whereas, if we dont replace second radiator, it may need to be replaced in a few months. I will be using OEM radiators.

Is it good advise to replace both at the same time? FYI, the car has done 70k kms (approx 43.5k miles).

[Joe-BMW33]

What is the labor total on the fix? If it's over $350 USD, you can pretty much expect to pay that twice if the second radiator goes. It's a matter of rolling the dice and paying labor twice or paying for the extra radiator now and including it.

I know I am stating the obvious, but for me, it would be, am I willing to take the risk at the price tag of $350+ (example) to go in again or do I want to shell out now for something that may never fail.

These radiators haven't been a known issue. I wonder if a rock hit it.

Without knowing all the numbers, I think I would pass on the second radiator. That can't be a cheap part.

[adhrp]

When I had a coolant leak recently in one hose and had to pay $1000 in labor to replace a $100 hose, I asked the SA to replace the other hoses but he discouraged me from doing so since they all looked good. I think that was sound advice and I took it. The same might apply here. I have not heard of radiators leaking at such low mileage without a rock hit or similar damage, so doesn't seem necessary to replace a part that would otherwise not spontaneously spring a leak, especially at such low mileage.

[lanlilan]

If they're pulling both radiators out to replace, you could also have them install rock guards for added protection.

Main radiator rock guard: 17-11-8-741-573
Aux radiator rock guard: 17-11-8-742-470

[bym007]

I went ahead with them replacing both radiators. Lets hope there are no more stone punctures in future.

Originally Posted by lanlilan

If they're pulling both radiators out to replace, you could also have them install rock guards for added protection.

Main radiator rock guard: 17-11-8-741-573
Aux radiator rock guard: 17-11-8-742-470

Is this part of the new radiator assembly ? Called the dealership to find out this needs to be ordered separately. But they advised, that I only need one of these sitting at the front of the assembly. This is a bit confusing. Can someone simplify it for me please ?

[EDIT]

Never mind, found the right part.

[Joe-BMW33]

If the radiator puncture was caused by a rock or foreign item, couldn't one argue that even a brand new radiator is just a susceptible? I guess if the second radiator was fine and you are doing the shields, I think I personally would pass on spending money on the second radiator unless it were cheap. This all assumes your main radiator puncture was caused by road damage and it sounds like it was since you are doing the shields.

I trust my dealer in general, but I definitely scrutinize the "while we are in there, you should do...." stuff. Makes sense on some things that are likely to fail with high miles, but you have low miles.

[bym007]

Turns out the leak was not caused by a rock, one of the plastic connectors had prematurely failed. Hence it made sense to replace both radiators. It did cost me dearly though.

The labour was about 670$ Australian.


Anyway the car is back and I will keep an eye on the water levels.

[bym007]

However I am noticing the rpm pushes for a few seconds while idling when the Aircon is working. With Aircon off, it does not happen. This was not the case before replacing the radiator.

Could it be due to a belt not seated correctly? I will take the car back to the workshop, but trying to validate my analysis beforehand.

https://youtu.be/v1TB2lUvCVc?feature=shared

[bym007]

I have noticed the jumpy rpm issue has settled now. I had an opportunity to drive the car for about couple of hours over the weekend, and it has not occurred since.

My guess is that it was unsettled A/C compressor pulley tensioner belt, which has now settled.