Smell of oil burning after turning off Discovery II

[Texasbear]

I just replaced my engine in a 2001 Discovery II and the old engine was shot. It had a rod knocking. Anyway the replacement engine has only 36k on it. It seems that when I run the truck for awhile and turn it off, I can smell a slight burning oil smell. Especially in the garage. I have a white rug under the vehicle and see no spots. Could it be from the recent swap and a lot of greasy hands touching stuff or do you think that there is oil dripping down somwhere on the exhaust. I would think that if it where greasy hands and oil left over from the swap it would eventually quit, right? Also, How often should I check my oil and how often to replace. What should I replace with as well. I have read the owners manual and know what it suggest, but just wondering if someone else has a better option.

Another question is that I had to also replace the cats on th exhaust when I put in the new engine. They seem to get hot. I know they are suppose to, but how hot. They have about 300 miles on them and they are kind of rainbow colored already. I have looked under the truck at night after a day of driving and they are not glowing, but I have noticed some slight smoking on the edge of one. Think this is a problem?

I was told by my mechanic that he thought that my first engine threw a rod because the cats where blocked. I have had it diagnosed, but if the cats where melting shut, would'nt my check engine light go off from the O2 sensors pre cats?

Thanks, Texasbear

[singingcamel]

probably the valve cover gaskets , tighten them or a least check them. using , any oil or spots on the deck?