Apocolips

I hope that all of you folks out there will bear with me. I am just learning the inner workings of Corvettes. My 1970 had been wrecked in it's earlier life and I am trying to put it back together as close to original as my budget will allow. I have seen some references indicating that the 1970, automatic, with A/C did not use an expansion tank. Can anyone confirm or deny this for me. Thanks

72GACRZR

My '72 auto,air, 350, didn't have one. Don't have my reference books handy, but that sounds right. If no one else chimes in, I will try to look this evening. :seeya

Apocolips

Thanks, I appreciate all the input I can get.

TNT

Your rite! A very helpful piece of info would be an NCRS judging manuel. Thad

jrzvette

One way to check is to look at the inner fender walls (assuming that they weren't damaged and replaced).

If the car did not have an expansion tank you should be able to feel four small "dimples" where the tank would have been mounted on cars so equiped.

The L46 (350/350hp) engines from 1969 and 1970 did not have the tanks, while the base engine cars did. GM recommended that on cars without the tank the radiator be filled to no more than 3" from the top with coolant. The radiator in effect was also the expansion tanks for these cars.

Jughead

My '70 didn't start out with an expansion tank but I added one soon after I bought it. I use the aluminum type as an "over-flow" type tank. The aluminum tanks aren't cheap, but the look good. It sure beat having the radiator vomit coolant all over the garage floor after a run.

You can barely see it in this old pic.

Bluesting70

I know this is an old post but I’m putting everything back together after a new crate 383 and the small hose just below the rad cap that would normally go to an expansion tank I can’t remember where it connected. Can anyone chime in on this?

bobby70

MY 70 small block with AC did not come with the expansion tank

PJO

See attachment this what we at the NCRS came up with when I was head of the Chassis team.

Bluesting70

Really appreciate the response PJO. I’m not able to download the link though. I’m guessing the “puke” hose just ran down the side of the radiator for overflow? My stock rad shows a cold fill line if about 3 inches down from the top of the fill hole.

PJO

Changed to a PDF hope it opens now for you.

vettebuyer6369

Theres no reason to post to an 18 year old thread to ask a question. Please start a new thread.