Good quality masking tape on engine block?

[chewychevy67]

I'm going to be painting my engine block here soon. I will need to degrease it and metal prep it. Is there a tape I can use so to keep these out of the exhaust valves and such? I just did my intake manifold separately and the tape I used became soft as soon as I used metal prep and paint/ cleaning solutions bled inside. On the block I can't have this happen as it is assembled and the intake and oil pan are already painted separately . Thanks.

[Llay R. Rac]

I cleaned and painted my engine, (I-6) while in the truck with manifolds and water pump removed. I cut pieces of the type of water proof wallboard used for shower and tub enclosure to match the shape of the manifolds and water pump, drilled the holes and mounted them using silicone sealer and short bolts. i wanted to use aluminium plate but didnt have any on hand.
for your oil pan maybe get a junk pan to install while cleaning.