Evacuation procedure.

Friendly format provided to inquire about automotive a/c systems.
Archived Forum

Moderators: bohica2xo, Tim, JohnHere

Post Reply
User avatar
Tim
Site Admin
Posts: 1103
Read the full article
Joined: Tue Apr 12, 2016 2:19 pm
Location: Scottsdale, Arizona
Contact:

Evacuation procedure.

Post by Tim »

I think this needs to be mentioned again. This theory you need to hold a vacuum for 24 hours to support a leak-free system is not really a great idea. Systems can hold pressure under a vacuum and not under pressure. The system can hold under pressure and not in a vacuum.

https://www.autoacforum.com/viewtopic.php?f=4&t=13603
------------------------------
Please support ACKITS.com for your Auto A/C Parts and Tool needs.

Help Support the Forum
B52bombardier1
Posts: 37
Joined: Sat Aug 31, 2019 6:21 pm

Re: Evacuation procedure.

Post by B52bombardier1 »

Hello,

This is absolutely true and something I've recently seen on my 70 El Camino. It developed a leak so we pulled it down and it held vacuum very nicely. Then we added some refrigerant and it leaked liquid like a volcano at a bad fitting crimp. Yes, hard to believe with such a big leak under pressure but yes, seen it!!

Rick
1970 Chevrolet El Camino 5.3 L LM7 Truck Engine & 4L60E Transmission
User avatar
Cusser
Preferred Member
Posts: 846
Joined: Sun Apr 24, 2016 6:29 am

Re: Evacuation procedure.

Post by Cusser »

I myself observed a related/unrelated event about 4 decades ago on my sister's Datsun truck:

The rubber fuel line to the mechanical fuel pump had a pinhole, so the fuel pump could not pull a vacuum, would just suck air through the pinhole. But no fuel ever leaked out that rubber fuel line.

Funny too is that a mechanic told my sister she needed a brand new fuel pump, which she purchased, and that new one was bad, so we used the existing fuel pump after I cut off 1-inch of the bad rubber fuel line. And the parts store finally gave in and refunded my sister's money.
Post Reply