Hello, new to the forum and hope someone can shed light on this subject. Working on my daughters 2008 R55, blew a radiator hose on the freeway but was able to pull to the emergency lane and engine died. Had it towed home and checked sure enough, coolant splashed everywhere in the engine compartment. Decided to pull head out, get it re-surfaced, install new gasket and seals, new head bolts etc. Here's the issue, before I pulled everything apart, there was no coolant inside the engine, after putting the top end back together, with correct torque, new HG etc., when I fill the system with coolant, I can see it coming out of the center front and rear head bolts. Do the bolt holes of these engines go through the water jackets and require thread sealant during install or is the head fubar?

 

I guess this has never happened to anyone, cheers.

 

Did you install a + 0.3 mm thicker head gasket? After machining head, a new head gasket with thicker
rubber coating needs to be used.

The water jackets are isolated with those rubber coatings.

 

Thanks for your reply. I asked the machine shop how much did they skimmed off the head and said 6 thousands of an inch not enough to warrant a thicker head gasket. Do you think I have to go with a thicker one? And if so, who would be a good source since my search always comes up with the standard .90mm thickness.

 

You have to have the surfaces immaculate before reinstalling with gasket. I'm talking immaculate. The un-resurfaced side has to look pristine. Use one of those green scotch guard pads. You will need three or four of them cut down in size. Clean surface till it looks polished.