I apologize if there is a thread on this. I couldn't find anything other than relating to attaching the dipstick to the block.

My car has a 400 swap, and the previous owner did the dipstick with the swap. The tube will not stay in the block. Do I need to use some kind of adhesive? Could I buy a new dipstick tube and it will seat properly?

Thanks I'm 19 and new to engines.

 

Most people use a little RTV sealant (permatex ultra black) on the dipstick tube near the little ridge that stops the tube from going in any further into the block. It'll help hold it in a little, but it's mostly to prevent leakage. It should be a slightly snug friction fit. It you have enough crankcase pressure to blow out the dipstick tube though you most likely have a problem. Are you running a PCV or breather or anything on the valve covers?