Quadruple length o

There's a word in my Japanese dictionary "oou" (ô.u) meaning "cover,
place something on, spread over". If this verb is regular, then the
presumptive[1] form of it would be "oooo". Is there a glottal stop in there
or some other way of seperating the two long o's in "oooo" or is this a
real quadruple length o?
Now if it's used with a noun that ends in a long o, you could get a monster
sentence like:
mukoo o oooo to omoimasu "I think I'll cover up the other side", with seven
o's in a row. Is this broken up somehow, or does it come out as one
amazingly long o?

M

[1] Or whatever the right term is for the -oo form.