I think my daily driver BMW M5 has developed a water leak at the head gasket. I just barely limped home late last night and have not had the time to exactly pin-point the source.

I loses about one gallon of coolant every 10 miles. The leak is hardly noticeable at idle but at 3,000 rpm and 65 mph it does not take long for the low coolant light to come on and the temp to start rising ... especially in 95 degree heat. The last 100 miles after the leak started took quite a while!

How big of a hole wil products like "BARS LEAK" plug?

Cheap POS BMW! Can you believe the head gasket sprung a leak after only 309,000 miles?

Thanks

Eddie

I'd use K&W Block Seal for that. Back in the day I had a Chevy Luv (how long since you've seen one of those?) with a bad head gasket, about the same as yours as far as water usage goes. I followed the instruction on the can exactly and drove it for a year and a half like that. I didn't replace the head gasket until right before I sold it, I didn't want to sell a time bomb. I also had good luck with it in a Volvo, lasted about 6 months before I fixed it properly, never leaked.

BTW, some purist engineer types will post telling you that you should never use a product like this, you should fix it properly, and they're completely correct. But you might not have a day and a half and several hundred dollars right now, so I say go for it and damn the consequences!

With over 300k, I'm sure your warranty is up?, but an authorized VW dealer apparently put some sort of stop leak in my wife's radiator after damaging it (while changing out a broken fog light), rather than replacing it.

Long story short, at 35k, the car overheated (big time) and guess what ... VW of A is claiming th warranty is voided due to the stop leak substance. The dealer wants $6500. to effect repairs.

Guess what VW of A ?

I'm surprised nobody suggested JB Weld. I thought is was a "must have" in a 914 tool box along with duct tape and bailing wire (safety wire for the racers).

I used JB Weld to repair a coolant leak on an Audi 5000S and the head gasket. The gasket was cracked and water would squirt out under pressure. A wire brush, brake cleaner and JB Weld and the leak was gone for years and years.

Eddie

just remember the stuf you pour into the coolant doesnt just go to the hole. it goes thru the entire system. which means your heatercore, radiator,leak, and all the passages.

steve