I am about to bolt in the csr and was wondering if I should use RTV or rely on that tiny tiny o-ring for a good seal. The pump surface is good but that o-ring looks a little shakey. I know you don't want chunks of RTV to get in the cooling system but if you're careful, shouldn't be a problem right?
BTW, did search but didn't find anything regarding use of RTV

 

liquid teflon

Z

 

had mine on for about 3 years no leaks and no 2nd gasket