BMW V-8 coolant leak defect
Last year, we had a customer come to us with a very severe coolant leak in his BMW 545i with 73K miles on it. As it turns out, BMW’s V-8 motor design has a flaw that should ultimately cause all of the V-8 motors to need this same repair.
Our customer described the symptoms as an overheating engine along with a burning antifreeze smell. One might suspect the waterpump and or thermostat to be the culprit. However in this scenario we noticed the coolant bleed hole next to the waterpump was gushing antifreeze. Further investigation was required.
Through extensive research we found that the seal bonded to the coolant pipe inside the engine fails. We could replace the waterpump all day long and not fix the problem.
BMW is aware of the issue. They say to fix the problem, it requires removal of the front of the engine and timing cover case. Then replace the coolant pipe. The only problem with that is it is not a solution, because you are using the same coolant pipe that BMW started with in the first place. It will fail again, not to mention the extraordinary expense, upwards of $5-6K and possible 5-7 day time frame.
We found a company in California which makes a custom designed specialty coolant pipe manufactured for this very problem. The repair was still not cheap as far as cost of maintenance goes, the repair was done in a few days, and for a third of the cost originally estimated to the customer.
We are so pleased to find a true fix to a problem that may seem insurmountable on the surface. Happy customer, happy shop!