Notices

pulling vaccum

Thread Tools
 
Search this Thread
 
Old Aug 19, 2007 | 08:13 AM
  #1  
idifamilycab's Avatar
idifamilycab
Thread Starter
|
Senior User
Joined: Apr 2007
Posts: 124
Likes: 0
Question pulling vaccum

whats the purpose of pulling a vaccum on the a/c system other than making sure it doesnt leak?

ive read about it boiling any water in the system out. But will there be water in a freshly cleaned and assembled system.

are there any other reasons to pull a vaccum?
 
Reply
Old Aug 19, 2007 | 08:43 AM
  #2  
losttxn's Avatar
losttxn
Freshman User
Joined: Aug 2007
Posts: 37
Likes: 0
From: Stationed in Maine

You pull a vacume primarily for removal of moister the longer you pull the vacume the better all the way around. On a system that has been exposed to the eliments for an extended amount of time requires longer vacume but if you just exposed the system for repaires you may need from 15min to 30min and for a system that has been open longer maybe around 30min to an hour.
 
Reply
Old Aug 19, 2007 | 09:02 AM
  #3  
lsrx101's Avatar
lsrx101
Fleet Mechanic
Joined: Feb 2006
Posts: 1,776
Likes: 5
From: Lorain County, Ohio
Club FTE Gold Member
Originally Posted by losttxn
You pull a vacume primarily for removal of moister the longer you pull the vacume the better all the way around. On a system that has been exposed to the eliments for an extended amount of time requires longer vacume but if you just exposed the system for repaires you may need from 15min to 30min and for a system that has been open longer maybe around 30min to an hour.
Good answer ^^^

Evacuation also removes air (a non condensable gas). Although you can see a leak if you lose vacuum, it isn't actually used to verify the system integrity. There are places that will leak under pressure but not under vacuum, so it's not really good for "leak testing".
 
Reply
Old Aug 19, 2007 | 12:08 PM
  #4  
Cuda_jim's Avatar
Cuda_jim
Post Fiend
Joined: Oct 2003
Posts: 5,903
Likes: 1
From: MICHIGAN
Originally Posted by lsrx101
Good answer ^^^

Evacuation also removes air (a non condensable gas). Although you can see a leak if you lose vacuum, it isn't actually used to verify the system integrity. There are places that will leak under pressure but not under vacuum, so it's not really good for "leak testing".
Best answer^^^. I found out the hard way. Pulled a vacuum, didn't lose any vacuum for 2 hours, charged the system...found a leak
 
Reply
Old Aug 19, 2007 | 06:46 PM
  #5  
idifamilycab's Avatar
idifamilycab
Thread Starter
|
Senior User
Joined: Apr 2007
Posts: 124
Likes: 0
Angry

well thankyou so much for all the info, i was able to charge my system and it was nice and cold. Did you catch the key word? WAS....for about five minutes. Turns out the p/o mounted two extra tranny coolers and one of which has rubbed its way through one of the condenser coils. Worked for about five minutes nice and cold then,...pissssssssss. that sucks. At least my boneyard compressor is good and everything else worked good.

Question,....is a condensor coil able to be welded or brazed? Its pretty easy to get to since its on the side of the condenser? or do you think i should go for a used one? New condenser goes for about $149 at autozone or i
may be able to get a used one for free from a buddy's parts truck.

Last question. Those dang 134a update fittings...low pressure side when screwed on tight, its own valve core extension i guess pushes on the old one and wants to let pressure out. theres no actual seal on the valve core on the update fitting, Its more like just an extension. Should i back out the valve core extension until it stops contacting the valve core on the acumulator, when its not being pushed?(i hope your not confused)
The high side had no valve core or extension in it so i left the old r-12 valve core in and put the 134a fitting on over it. Is that right?(i hope you're not confused again.

sorry about the long post i guess i have a lot of things to tell and ask about.
Thanks again
 
Reply
Old Aug 21, 2007 | 05:40 AM
  #6  
losttxn's Avatar
losttxn
Freshman User
Joined: Aug 2007
Posts: 37
Likes: 0
From: Stationed in Maine
Wink




OK first off CONGRATS and Im Sorry , Ok as far as your coil goes Yes It can I have sent some off to the radiator shop down the road, and they work wonders. As far as your fitting question, good job you did it right.
Just keep in mind if it works the first time then its not a ford lol.




Originally Posted by idifamilycab
well thankyou so much for all the info, i was able to charge my system and it was nice and cold. Did you catch the key word? WAS....for about five minutes. Turns out the p/o mounted two extra tranny coolers and one of which has rubbed its way through one of the condenser coils. Worked for about five minutes nice and cold then,...pissssssssss. that sucks. At least my boneyard compressor is good and everything else worked good.

Question,....is a condensor coil able to be welded or brazed? Its pretty easy to get to since its on the side of the condenser? or do you think i should go for a used one? New condenser goes for about $149 at autozone or i
may be able to get a used one for free from a buddy's parts truck.

Last question. Those dang 134a update fittings...low pressure side when screwed on tight, its own valve core extension i guess pushes on the old one and wants to let pressure out. theres no actual seal on the valve core on the update fitting, Its more like just an extension. Should i back out the valve core extension until it stops contacting the valve core on the acumulator, when its not being pushed?(i hope your not confused)
The high side had no valve core or extension in it so i left the old r-12 valve core in and put the 134a fitting on over it. Is that right?(i hope you're not confused again.

sorry about the long post i guess i have a lot of things to tell and ask about.
Thanks again
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Witty73
1973 - 1979 F-100 & Larger F-Series Trucks
15
Oct 20, 2010 10:35 AM
Flame Out
1999 - 2016 Super Duty
5
Jan 23, 2007 09:12 PM
dbarracuda
1973 - 1979 F-100 & Larger F-Series Trucks
5
Mar 12, 2002 09:16 AM
4fords
1973 - 1979 F-100 & Larger F-Series Trucks
4
May 15, 2001 11:14 PM
Katt
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
9
Apr 13, 2000 07:54 AM




All times are GMT -5. The time now is 01:56 AM.

story-0
10 Ways Ford is LOSING to the Competition

Slideshow: 10 ways Ford is losing to the competition

By Joe Kucinski | 2026-06-15 09:52:01


VIEW MORE
story-1
Top 6 Best Deals Available on New Fords & Lincolns Right Now

Some great targets in today's expensive world.

By Brett Foote | 2026-06-15 09:35:19


VIEW MORE
story-2
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.

By Verdad Gallardo | 2026-06-12 11:01:55


VIEW MORE
story-3
Top 10 Fords at 2026 Carlisle Ford Nationals

Slideshow: Top 10 Fords at 2026 Ford Nationals

By Joe Kucinski | 2026-06-09 11:10:08


VIEW MORE
story-4
3 Best / 3 Worst Parts of Modern Ford Ownership

Based on years of owning multiple modern Ford products.

By Brett Foote | 2026-06-09 10:53:36


VIEW MORE
story-5
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

SPONSORED: From muddy boots to rain-soaked cargo, these upgrades address some of the most common frustrations Ford truck owners face every day.

By Pouria Savadkouei | 2026-06-08 18:50:34


VIEW MORE
story-6
Every 2026 Ford Engine Explained

Here's everything you need to know about every Ford engine available for the 2026 model year.

By Brett Foote | 2026-06-05 12:58:01


VIEW MORE
story-7
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-8
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-9
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE