AN hose / radiator fitting size / PS question

[chalet2506]

Anybody know what size the tranny cooler line fittings at the radiator are on a 72? I thought 5/16 1/20. Trying to find the right connector to run 6an hose to from the tranny to the radiator. Already have the fittings for the tranny, hose, and hose ends. Just need the connectors to hookup at the radiator.

Bought these based on what I read on the web and they are a little big.

http://www.summitracing.com/parts/EAR-961946ERL/


Also. Any reason not to run this hose for a power steering pressure line? Says its good to 1000psi. I've got 20' and thats more than I need for the tranny/cooler work.

http://www.summitracing.com/parts/SUM-230620/

I did order some earl's powerflex hose for the ps line, but looks like they sent me 4an instead of 6an. Thinking now I can just use the cheaper summit hose since I have extra and send the Earls back.




Thanks in advance

 

[dyeager535]

Your pressure line may run more than 1000PSI. You might search to check what actual line pressure is, but I know the pumps were good up to something like 1200 or more.

 

[chalet2506]

Thanks. Any idea what size that radiator fitting is?

 

[dyeager535]

No, sorry. If I was guessing it would be 3/8 or 5/16th, but that doesn't help I'm sure.

 

[chalet2506]

Looks like problem with the fitting is I have 5/16th tapered threads and radiator needs straight threads. That has been bugging the crap out of me all day. Guess I'll run to Napa and see if I can find an adapter.

 

[JDNobodi]

That fitting that you posted from the summit site should be the right one.
5/16 inverted flare with 1/2-20 nut. 1/2 = .5", 20 = 20 Threads Per Inch.

Only thing is, you're not using tubing. That fitting has the flare at the bottom be used in place of the flare on the now nonexistence tubing.

 

[diesel4me]

Far as I know,all GM's that vintage ran 5/16" tranny lines,with the 1/2"x 20 thread fittings ,though I've seen a few TH400's that had 3/8" steel lines with 5/8"x 18 threads...there isnt any 5/16" "tapered" fittings,what you have is likely 1/8" NPT pipe thread,thats pretty close to 5/16 or 3/8" threads,they do sell brass adapters to let you couple steel lines with flared fitting to pipe threads,that probably what you have...the trans cooler in the radiator may have had 1/8" pipe threads and used a brass adaptor to let the 5/16" lines couple to it..

 

[chalet2506]

I'm starting to think its the Earl fittings. Found some 5/16 brass flare fitting adapters at napa and these won't fit into them. Double checked with some 5/16 line fittings they had there and they would fit the brass adapter just fine. Size and pitch on the earls fitting I got from Summit and the line fittings at Napa are the same. Guy down @ Napa was stumped also.

 

[Teck]

Not sure what ones I used but can try to look. I think I picked them up at Smiley's and they where fittings that where labeled for a carb.

 

[Teck]

I do have the old set of blue fitting at the shop if you want them.
The silver one is the ones I change from the blue ones I had in there.

 

[chalet2506]

CK5 fairy showed up Monday - Thanks Brian. Got the fittings, now just need route the hose. Guess I'm just going to get some insulated clamps and run both tranny lines down the top of the frame and move the starter cable either inside the frame behind the motor mount, or clamp it to the inner fender once the front clip is back together.