ok i was driving spirited and all of a sudden a plume of smoke took hold of my car, knew it was coolant right away, first thought was coolant seals.



stopped noticed smoke only from bay, figured since i replaced the hole left side it had to be the right side.



sure enough heater hose (form under filter to the cabin) exploded.



any ideas as to why my coolant system is so pressurized or could it just be due to 14 year old hoses?



ive replaced the thermostat and gasket, fixed leaky thermostat housing, replaced turbo coolant hose, and radiaor hoses, replaced radiator with fluidyne, everything.



would a bad rad cap cause this?



kevin.

14 year old hoses don't help..



But yeah a bad rad cap wouldn't let excess pressure spill into the overflow.. What pressure is the rad cap you have?

I've seen it happen on several Rx-7s. I believe its just old hoses. Everyone should replace all hoses as soon as possible.

i think the stock cap is 12 psi, double check and make sure you cap is the same and that the diaphram hasen't rotten off.



you can get a pressurization kit from like sears or something for not too expensive, and try to manually pressurize the system to see if the cap is working properly.



or you can take it to a local mechanic who will check it for you.

i got a fluidyne rad and cap, its 1.1bar IIRC so about 15psi +/-1psi.



ill test my cap at the shop tomorrow hopefully its just old hoses.



thats like the ONLY hose i didnt replace cause it looked fine.



kevin.

Fourteen year old rubber on a car with the underhood temps of a T2? Hmmm.



I predict you will have only as many more problems as you have 14-year old hoses under the hood. https://www.nopistons.com/forums/pub...#>/biggrin.png



Sounds like you are good to go!

I replace that hose every 2 to 3 years no matter what! I also keep en extra one in standby in my storage bin.



I also replace all the hoses every 3 years or when they start/feeling weird.



C

Check the line goign to the overflow bottle, the cap in the overflow bottle, and the nipple on the radiator for the overflow bottle for blockage. I had a problem with that before.

yea that whole thing is unclogged, it was my problem when i ran 100% water and **** froze in the rubber line, but i fixed that and am running a proper 50/50 mix now.



everything SEEMS to be fully functional now, im going to run it hard again tonight and check the coolant levels again hopefully itll be all good.



kevin.

I ran a 75 water and 25 coolant mix (oh and a bottle of water wetter) in my rx7 for the summer.. I dropped the coolant out of the car and it's sitting in a jug in my garage.. Hasn't froze..



Cooling is more efficient with more water, no? I was curious to see if my mix would have frozen in the Canadian winter but I guess it didnt..

Not too long ago I down shifted to 3rd doing 60 to rap it out and grenaded that same heater hose.......i think its just old hoses, since i put a new one in i havent had any problems.

yea after driving two days im completely leak free in the coolant department...........woooooooooo



first time ever.



now once i replace that leaky PD ill be 100% leak free, woot.



kevin.

nope...water is the beest for heat transfer

yeah that line under the filter doesnt last because it gets oil spilled on it

that was my theory too, i guess i didnt post it here, but that was my analysis.



kevin.

so higher water ratio = good?

yeah....but watch out when its cold thats all





during the summer i use 100% water and water wetter

Yeah that's what I was thinking too.. I was under the impression you needed a little bit of coolant to keep the aluminum from corroding? That's why I ran 25/75 for the summer..

some people use that evans coolant to prevent corroding all together, yes don't even bother if it gets cold enough where you live, the stock cooling system when working correctly is probably well within any abuse you can give it.

i dont trust 100% water, honestly.



kevin./

in summer? why?

I wouldn't use 100% water..



I have a TII waterpump that sat in a leaky shed and after two months there was so much rust on it you could hardly tell where the fins were! I can show it to ya if you want, colin https://www.nopistons.com/forums/pub...IR#>/smile.png

that is my main concern with the 100% water thing, rust after sitting. my car goes through extended down periods and im not about to flush and fill my coolant system that often.



kevin.

Use distilled water when mixing in the coolant. Regular water has minerals that adds to the corrosion. Having a little coolants helps lubricate the water pump.

Thats why I thought you should always run a small amount of coolant at least.. best of both worlds?

******* rad. caps are a bitch they dont let out that stupid pressure and bada boom blowin hoses... replace all your coolant hoses that are 14 years old haha that shouldnt even be questioned