Drilling out broken bolt in engine block.. got a bad feeling about this.

[Blibster75]

Hello all,

I am running a 1990 dg 1.9 engine and was in the process of replacing a crusty exhaust system when horror struck and i snapped a bolt when removing the old manifold.

It is the lower manifold bolt on the nearside rear (closest to the rear coolant resevoir.. (i'll upload a pic when I work out how)

Long story short, I had committed to drilling out the snapped bolt and was making steady progress. I appear to have drilled slightly beyond the bolt threads and an amount of coolant has leaked from the drilled hole. I had drained my coolant to move some hoses to give me clear access to start the drilling so there wasn't much left in there anyway.

I'm guessing there is some form of coolant channel into he engine behind the bolt? Can anyone please confirm?

I am hoping that if I rethread and tightly refit the exhaust system it will still be watertight? Would appreciate anyone in the know telling me if this is a bad idea or making any constructive recommendations that may help me at this point...

Thanks

Rob

[Mocki]

[jrt]

Have a search on the forum, there’s some cross section photo’s showing how deep to drill.
Plenty of other info too.
viewtopic.php?t=162243

viewtopic.php?t=150162

David.

[Blibster75]

Thanks for the replies... I did a quick search on the firums and couldnt find anything so appreciate the links.. sounds like i have obviously f**ked up by drilling slightly too far but hoping a stainless grub screw with some high temp thread lock before I insert the bolt might allow.me to get away with it....

In other news the thread tap snapped in the drilled hole also.. so I have that to deal with first.. ffs