i just recharged my system with 134a refriderant. befor i recharged the system my compressor would come on for about 5 seconds and go off for a little more than 5 seconds (all on max A/c, similar on norm) after recharging the system the compressor will kick on (again this is on max a/c) and stay on for about 10 second if not more and will restart again roughly after 7 seconds... is this normal? do i need more refridgeant? is the clutch on the compressor gone? is the WHOLE compressor bad? im just not too sure... if you need more info i can help ya and if it really helps i can record a video

 

Sounds like you are still low on refrigerant.
What are your low and high sides readings?
The only way to know what the charge is right is to vacuum it out and weigh it going in.

 

I had one doing that a while back. Even after vacuuming and recharging the system. It turned out to be the engine fan clutch slipping. It would let the system get too hot when it ran, which caused high pressure and caused the cycling on and off.

If you have the refrigerant at the right levels you might want to check that.....but you do need to make sure it's charged right first. If you don't have the equipment, I'd recommend taking it and having it re-charged. Most places have the machine that does it and it can also check the temp/pressure after too.

Good Luck

 

I would have to second the first and second comments. I am an A/C tech and have my liscence to prove it. First check your refrigerant and how much needed. You may have to have it recovered. Be sure if you go to a mechanic to do this, ask them if they do an inspection on the a/c system after the recharge. I've known some places to recharge your a/c, and charge you are bundle of money without checking there work. Scandalous fouls out there!! When you get it home after a recharge, and you do not seem content with there inspection, get some soapy water in a spray bottle, and spray the soapy water on any connection that you can find to make sure there are no leaks present. This way you can take it back and tell them to recover/ recharge and do there re-inspection again because they suck at it! Just looking out for you man!

 

yes, thank you very much! i live right down the street from York Ford, where the truck was originally bought actually, and i know a tech there. He told me i was low on refridgerant so i bought the "A/C Recharge Kit for Dummies" the system took the whole can. It was hot here today and the A/C was definetly cold vs. the vent. The compressor does still kick on and off with roughtly 10 second intervals... sometimes it was on for more than 15 seconds... i dunno, should i add more refridgerant or is my best bet to go to York?

 

I doubt the compressor is bad if it did blow cold. You might still be down on gas. A/C's will seep/leak gas and need re-charging over time and it could need a couple of cans. I think I'd invest in another one if you have the kit that has the gauge to show if you are in the right "range". If that doesn't correct it then I'd spring for the vacuum/recharge from a shop........not the dealer......too expensive. Ask some of your friends about shops that have done some A/C work for them.
See if your tech friend can do it on the side or he may be willing and able to hook up to it and see if it is still low.

Good Luck

 

My 89 was short cycling when I bought it. It took 3 cans to fill (short cans) I'm not an ac expert but I do not think it can be overfilled.

 

Well, you are right about overfilled but you are also wrong. Typically you can overfill a system, but in this case where your compressor is cycling on and off you may be low on refrigerant like the above threads say. It will cycle on and off when there is not enough refrigerant in the system. Also check the electrical components and make sure everything works. The best check does not have to come from a dealer. Like 92F150Flare said you might want to ask someone who has a recovery system. I am a tech and would do it for you no problem, but the only problem about it is i have no recovery system. They tend to be very expensive. You might want to ask for a hook up on the side. What they will do is recover the refrigerant from the system and charge it with nitrogen to completely get rid of all the moisture. After this your system can be recharged with the refrigerant of your choice seeing as though they get the left over refrigerant out when they recover it. If you do get someone to help you out, check and make sure they know what they are doing. All of this includes putting a vacuum on your system/ charging with nitrogen...if needed/ and then recharging. Inspect and check for leaks and then test. DO NOT test on high. Test on low and give the refrigerant a chance to cycle through your system. The cycling should stop after proper charging. Also have your ac tech check if there are any solenoid switches that may go bad so that they can replace them. If there are have this done because this may also cause your cycling problem. I'm not sure if your truck has them or not, varies. Hope this helps!

 

is it possible to over fill? i dont know for sure, but if some one could tell me that would be great!

 

I would say yes you can over fill the A/C system.
If you over fill an A/C system the head pressure goes up higher and may blow a weak hose, turn off the compressor on high head or lift a safety valve. Also the gas mileage would go down and the belt may slip.

This would also raise the low side so the duct air will be warmer.

 

Again I'm far from being the ac expert. If filling from the cans available from the parts stores I dont see how it is possible to overfill? There is only so much pressure in those cans correct? I can see having commercial size tank with a regulator it would be possible. 134A under pressure is a liquid and virtually un-compressable. Once in the system only the air is compressable. I am most likely missing something.

 

You put the gas (not liquid) in on the low side with the engine running and the low side will be below 65 psi and if you put the can in hot water to get the gas out the pressure in the can will be higher.
There are no regulators on the large tanks and the pressures are the same the only difference is you may not need the hot water.
You do not compress air in an A/C system, only gas.
Liquid from a flooded evaporator from an over charge may get to the compressor and will destroy it.

 

Think I got it. Its filled on the low side as a gas. Is compressed to a liquid. Allowed to expand/evaporate (cooling takes place) And then its compressed again etc.

 

It is compressed to a high-pressure gas and then cooled to a high-pressure liquid in the Condenser.
You need to understand Pressure Temperature Relationships to understand how all of this works.

 

Yeah I agree. It is a whole other field to train your mind to think opposite sometimes when it comes to A/C systems. Some things sound backwords and Press. to temp. relationship is something you have to be trained on.
Just a reminder, you cannot compress liquid. A compressor pumps gas from a low pressure to a high pressure. This is the heart of your system. When you put your refrigerant in on the low side this means on the opposite side of the discharge on the compressor. This is comprised of steps...Compression/Condensation/Expansion/ Evaporation. These are the 4 main steps to the A/C system. I could go into depth but I would just confuse you. All you need to know is that it is probably not a good idea to charge your system yourself. The reason for this is if you recover R-12 and replace it with R-134, and have not fully recovered all the ref. oil/R-12 you will cause your compressor to die and the system will have to be recovered again by a technician and it will be just a waste of time/money!

You cannot overfill the a/c system. I am not pinging on you SubFord because I did say in a prior post that you can...I could not remember and I was wrong about overfilling. This will cause refrigerant not to flash over into a gas and make its way back to your compressor. The evaporator cannot keep up with how much ref. is in the system when it is at a higher pressure on the low side and in liquid form. When this happens...recover/ replace/recharge and have plenty of money on hand because it isnt cheap!

Hope I helped a little. Sounds to me Subford that you have had some training? Keep it up man!