1993 M900- It begins.....

[spacemonkey]

Originally Posted by utopia

Googling around, it seems that the acetic acid in white vinegar is a solvent for oxides of zinc.
Presumably its the swollen corrosion of the zinc plating that's causing the problem.
I'm guessing you've perhaps already tried this, but I thought it worth a mention just in case.

I assume you're also familiar with those plumber's heat proof mats.

Thought about all kinds of things to free the corrosion, but it's getting the fluid into the corrosion which is within the engine block where the bolts go. Some dummy put a frame in the way! I have heat mats but I'm thinking I might remove the heads etc and fix them and paint the block in situ then reassemble and finish the rebuild and try to remove the bolts once the engine has been thoroughly thrashed and hot, then replace with new bolts which are properly protected with the right kind of grease.