Literally... I noticed a bit of leakage around the seal between the filler cap assembly and the water pump neck. There are two 10mm bolts holding the cap assembly on. I took out my #10 wrench to make sure they were tight and as soon as i TOUCHED one of the bolts, BOTH broke completly off sending the assembly flying and a cloud of burning hot coolent everywhere. I extracted the what was left of the bolts out of the mount, and now I need to know what size and thread they are so I can get replacements.

 

M8 x 1.25 as I recall. About 2" long. Get stainless this time, and cover with anti-seize.

Edit...Oh, you mean the bolts that hold the little plastic rad cap mount on? M6 x 1.0

 

yeah, but they were 10mm bolts, so wouldn't it be M10 x something?

 

10mm is the head of the bolt not the thread diameter, what is wrong with the old bolts?

 

They literally shattered into 3 or 4 pieces. Here's the piece that came flying off...

 

Holy s$#t!!!! next time wait for it to cool down a bit before you play with the cooling system. I had to learn that the hard way too.

 

The size of the head has nothing to do with the size of the threads.