sealers

Hi, looking for a trade adhesive for bonding in steel water pipes etc to 'stat housing's and other parts like breather tubes . Strange request maybe but trying to find o.e. stuff is not easy. Also face sealer for gearboxes and crank cases. Manufacturers use a grey sealer that goes off hard and...

I need one. i probably won't have a choice on which one but has anyone tried one and it worked ? I think the leak is from behind the timing belt so its a major operation to find and sort. I will try a sealer first.