radiator smoking!?!?!

[The datsun kid]

hey guys so i have a 71 521 and its got the l16 and the guy before me put a 02' fiero radiator in it and its been fine until today i was drivin to my gpas for thanksgoving and all of a sudden the tempature gauge buried into the red and it started smoking from the hood bad so i pull over pop the hood and theyres coolant everywhere i mean everywhere! but heres the thing i cant find a leak anywhere i did notice the main hose from the radiator is really soft but theyres no leak or hole i filled it up with water and drove to gpas then i sit there and let it run and it dosent over heat but i notice smoke is coming from the radiator but the gauge is sittin in the middle so i drive it home and its fine all the way and when i get there its smoking out of the radiator but the gauge is still sittin in the middle so im lost any help guys??? id really appreciate it

[izzo]

Smoking outta the radiator?

 

Well, either its steam, or smoke. If its smoke, it could be a blown head gasket leaking oil into the water system, and smoking when it gets hot maybe? Wait for someone with more wisdom to chime in tho :D

[The datsun kid]

sry its steam not smoke

[datzenmike]

Probably ran low on coolant and over heated and boiled spraying all over. You need to check the coolant level when cold every week. Never let it run low and NEVER NEVER NEVER let it over heat like that. If it starts to over heat pull over and find out why. Over heat and you can easily blow the head gasket worse you can warp the head.

[The datsun kid]

ok il check it and i pulled over like secs after it started to smoke my cosuin warped his head before and i knew better

[The Stig]

That "newer" fiero rad might have plastic tanks, they can get hairline cracks that actually hold coolant when cold, so it looks full. But when the engine heats up the rad is unable to contain the pressure, this pressure is created as water/antifreeze expands when heated, and the elevated pressure also raises the boiling point of the liquid as well, so the loss of pressure also causes some of the remaining coolant to flash into steam, steam does not conduct heat from the engine very well and the water pump cant circulate it either, so in terms of cooling power you have fallen off a cliff. So what starts as a fine spray leak that is sometimes difficult to see, usually will result in a column of steam which (be careful) might be easier to spot the source. if all else fails try some dye usually used for Air Conditioning system leak detection, it will leave a trace that glows under UV light. GOOD LUCK

[banzai510(hainz)]

Its been cold here

Buy some anti freeze.

 

maybe block was frozen?

 

keep yur eye one it

[The datsun kid]

soo i bought a new main hose because the other one you could squish close with two fingers and now it runs fine i let it run for a good 35 mins and nothing but now my coolant is green but wait ummm i didnt put any coolant in it!! im fricken lost man maby the coolant from the block cycled back through?? i dont know any ideas?

[The Stig]

the antifreeze was probably sitting in bottom of block and is now mixing and circulating. You cant drain a block 100% while it is in the vehicle, be sure you have solved the leak and then drain and fill it again with water, and drain it again. Then fill it again with 60/40 mix water/coolant as old coolant/water mixes become acidic over time and will corrode your heater core and control valves.