I replaced my compressor with a used one. How important is it to replace the evap/filter also? Ive read you should but at 70 bucks, I dont know. Also my old compressor seized up so could debris be in my lines or possibly plug filter? I tried to charge the system but it won't blow cool air. The clutch wont ingage. So I jumpered the compressor and clutch ingaged and system took more freon. But when i tried to run without jumpering the compressor doesnt ingage. Possible problem I heard of was the outside temp being too hot. 100. I will try again in the morning when it cools. Any comment on this?

 

Yes you should replace the filter. It's insurance especially since you suspect there may be debris in the system. Also, anytime an A/C system is opened it should be purged, preferably with an inert gas like nitrogen. If you have access to a vacuum pump, pump down the system to 19" hg before adding the refrigerant. An old trick when adding refrigerant is to put the cans in a bucket of hot water first to heat up the gas. This increases the pressure in the cans and allows you to add the refrigerant faster. Keep in mind, if you manage to add too much refrigerant, the system won't cool properly. Gauges are a must to charge a system properly.

 

In fact, a lot of places require it to maintain the warranty on the compressor.
Also, since you suspect debris in the line, you should replace the oriface tube. The oriface tube has a filter on the inlet,and it has a metering device thatturns the high pressure refrigerant flowing from the compressor through the condensor into low pressure refrigerant ready to be sent to the evaporator.
Also, like Birdman said, you need to make sure the system is properly evacuated. The system needs to be brought to a vaccum of 26 in Hg (88 kPa), close the valves on the gauge unit, and turn off the vaccum pump. The system should maintain that vaccum for 5 minutes, if not, you have a leak somewhere. Than continue vaccuming out the system for another 10 minutes.
NOT properly evacuating the system after opening it to the atmosphere CAN/WILL result in bad A/C output, and/or system damage. Also, make sure you added the proper amount of refrigerant oil after you replaced the compressor, failure to do so can/will result in damage, or adding too much can/will result in lack of cooling power.
Further guidelines for changing A/C system parts, evacuation, charging, and all else can be found in the service manual.

 

Ok so now I'm scratching my head. What have I done wrong? I guess I'll buya filter and canister doohickey. 100 bucks. So I install the canister doohickey (accumulator) and orifice tube filter. Still no AC clutch ingage. This is getting personal now.Well maybe there's not enough freon in the system to kick on. Ive heard of that. Back to jumpstarting the compressor with some fancy custom jumpers. Start to fill the system and of course it takes freon. Take off jumpers and rehook to vehicle. Clutch won't ingage still!!! I'll just have to accept defeat and take it to the shop to get serviced. Call the shop and they can get to it in a few days. But I want to leave town for the weekend and with the temp at 100. No deal. I have a friend whos an HVAC guy. He comes over to help.We cant vacuum system with his equipment so we try to see if we can fill it anyway. I jumper the compressor he fills the system. We fill to recommended psi and still clutch wont go by itself. He leaves. I contemplate the universe and why its against me. Maybe a vacuum hose is loose at the control switch. Nope. All electrical connections seem in order too. HERE'S MY ADVISE!! Take a step back, grab the coldest beer in existance. Now it comes to me. Maybe I overlooked a fuse.I checked them twice already, in the cab and under hood and all I saw was an AC relay that I switched with a different one. Relays fine. There it is, right before my eyes. A tiny fuse that says AC Clutch/Horn. Hmmmm my horn hadn't worked for some time I forgot about it. Indeed the fuse was blown. The most non mechanically inclined quick fix of any vehicle. CHECK THE FUSES!!! My AC now works great and I get a horn again too. Its all about the beer. I still plan on taking it in to get professionally serviced though. Maybe not so soon. So to all who gave advise and to those who had similar problems. I sincerely thank you all..