i have an s13 with a j-spec ka24de
im having some problems with my rad hoses, they keep collapsing
at first it was upper which i replaced with a spring inside
but now its my lower hose that goes to the thermostat
i made sure my line was clear from my coolant resovoir to the rad so its not that.
any ideas what the problem would be ?
please and thanks guys the help is greatly appreciated 
Try a new rad cap
got a new one last month
also found a greasy substance on the bottom of my rad cap
what could leak into my rad to do that ?
Oil. Headgasket? Do an oil change and pay attention to the first little bit that comes out. Check your oil cap for milky residue. Do a leakdown test.
do a compression test on that jspec ka
Replace the lower hose as well.
^ While that’s worth doing, a shitty rad hose won’t just collapse because it’s shitty.
im lost
i opened my rad cap and released the pressure in the lower hose that goes to the thermostat, then i drove it today and kept it more in the range of 2,500 - 3,000 rpm and it kept my stock temperature guage normal,as well my hose didnt collapse today :S
but when i was keeping my rpms around 2000 my gauge would drop to the bottom, i think thats what caused the hose to collapse ?
am i driving wrong ?
headgasket
^^^ Sounds like a oil jacket is getting threw into your coolant jacket. I was finding more coolant in my oil than oil in the cooling system with my KA hg leak.
Taste your oil, no joke just a drop on your tongue. If its sweet like coolant you’ve got head gasket issues.
Or you could just check your dipstick.