A/C Question

[big van]

I have an 88 E- 350 15 pass. I charged the system & the front blew cold for a few days but got hot again. I figure there's a leak some where. the back never got cold but I think the heater line valve is probably bad so it was fighting against the A/C & won. I was going to clamp the heat lines off to check but I had lost charge by that time.
So my question is how to find my leak and Is it better to mess with it my self or go to a shop? I do any other work so that's not an issue, I'm just not that familier with A/C systems.
I've read in the posts about upgrading some parts to really get cold air. Being this thing is long I'm sure the kids wouldn't mind if it was a little chilly in the back! It can get a little hot back there now. Not much air flow in the back of a van.
I know some of you guys are A/C gurus so any info would be great! Thanks!

 

[MIDNIGHT RIDER]

As we speak, I am just taking a drink/break in the process of repairing my A/C system.

Like you, I know very little about it; but, due to financial concerns, the aggravation of having to fool with a shop, and just figuring I could do it myself, I read everything I could find, picked these guy's brains, and jumped in, head and ears.


I figure I ain't gonna ever learn if I don't do; and, once I get a little on the job experience, I will no longer fear messing with it and will have gained some basic knowledge.


Well, my drink-can is empty, so back under the hood I go.

 

[f350flatbed]

There is quite a bit involved if you don't know anything about it. If you have a leak somewhere you'll have to find it first with a leak detector of some kind and once you get that fixed you'll have to change out some pieces of the system to make it compatible with the new kind of refrigerant. Check the posts that Midnight Rider has put up lately to see what he has had to do. Ask away if you can't figure it out, we got a full inventory of specialists on the board! And then you got the rest of us too!

Paul B