I know I have seen a ton of those clearwater HF pumps in use, some work well. I imagine yours might be a thermal overload since it probably isn't a 100% duty cycle motor. I have no experience with them though, clear water vs something made for oils...
I run a 1hp industrial motor (100% duty) connected to an oberdorfer gear pump. not the fastest in the world, but will withstand the heat of the oil, self priming, can run my CF and will pump straight crap without issue.
So far I have gone through 2 of the cheapy HF diesel refueler pumps and a GPI 15gpm (tried pumping cold creamy oil too long). The oberdorfer has a few 1000 gals on it now and I bought it used ($100). Bought the 1hp motor used as well, $50. The oberdorfers are very well made and made in the usa for over a hundred years. This is my recommendo.
on the whole house filters, if I have a 10-5-1 configuration, my 10 clogs and the 1 clogs, before the 5mic clogs, so be aware that all three don't need to be changed at the same time. Now, how to figure which one needs to be changed without a gauge on each is a trick for which I have no trick.
My whf cases are rated to 100psi at 120deg, I let my pressure creep up too 100 and change them. I blew a cheap cpvc valve early on because of some pulsing, what a mess
. Everything is cast and brass now.