A/c
02-09-2013, 04:59 PM
#1
Registered User
Thread Starter
Join Date: Feb 2013
Location: Texas
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
A/c
2003 ram 2500 5.9 HO
A/C will not vacumm down but will hold 200 psi nitrogen without dropping pressure. It acts like it has a big leak but holds that much pressure.
Any help please thanks Brian
A/C will not vacumm down but will hold 200 psi nitrogen without dropping pressure. It acts like it has a big leak but holds that much pressure.
Any help please thanks Brian
02-09-2013, 05:35 PM
#2
Registered User
Does the vacuum pump work? Do you have both sides of the gauge manifold open and are the hoses attached to the truck properly and opening the valves. Does it draw down at all, if not it's probably one of those 3 things I mentioned.
If it draws down some then you do have a leak. A system can take a very long time to bleed off pressure through a pin hole yet put a vacuum on the system and it will show right away.
If it draws down some then you do have a leak. A system can take a very long time to bleed off pressure through a pin hole yet put a vacuum on the system and it will show right away.
02-09-2013, 08:59 PM
#3
Registered User
The first thing I check is the vacuum pump and manifold. Sure enough, my pump has a leak. After 30+ yrs. it still looks like new, inside, but the shaft seal is cracked. It would only pull 1300 µ's. Even a tiny leak that will barely make soap bubbles will keep you from getting below ~ 1200 µ's.Try pumping down your hose/manifold by itself and see if it holds. I've given up on any of the color coded hoses. They are good for about 1 yr and they start to leak. I only use the black HD hoses anymore. Craig