Community Forums

oldnavycdr · 08-28-2021, 08:20 AM

Great information in Ray's posting. In my case the system is all Denso. According to their manual my refrigerant capacity is 3#. Sure doesn't seem like much for the long run from front to back. I'll use a manifold set to check pressures when I tackle mine.

Dav L · 08-28-2021, 08:24 AM

Quote:

Originally Posted by oldnavycdr

Great information in Ray's posting. In my case the system is all Denso. According to their manual my refrigerant capacity is 3#. Sure doesn't seem like much for the long run from front to back. I'll use a manifold set to check pressures when I tackle mine.

The lines hold very little oil. Most is in the compressor (by far). Some is in the evap, and some is in the condenser. Each one has a recommendation of how much oil to add if that component gets replaced (to replenish the amount of oil lost to the system).

CRV2 · 08-28-2021, 09:14 AM

Quote:

Originally Posted by Dav L

I am leery of their "compatible with all AC systems"...if that was the case, why is there a shelf full of oil types on every parts stores shelf. If there was the magical "fits all" single oil.

But you found the can. Power of the Internet. Thanx for sharing.

Amazon (and some retailers) also sell something similar with PAG 150 oil, which is probably what I purchased as I agree that using the same oil is best. I am not sure about "performance" enhancers though as what I used didn't have that.

https://www.amazon.com/Interdynamics...0162537&sr=8-3

Also, there are oil injectors for adding liquid oil into the system.

https://www.amazon.com/dp/B01N95O7UZ...xpY2s9dHJ1ZQ==

The oil testers are a little better than nothing, many times I have had leaks on some equipment and vehicle's a/c systems and if the leak was\is in a low spot (like at the rear of the compressor) then it is hard to know how much oil may have been lost. Also, I hate to release any of the freon if not required to do so, many times all that is needed is to add a some (lot less) freon to the system than if the system was completely empty and as long as there is some pressure then there shouldn't be any moisture in the system so no vacuuming needed. Of course when replacing components, then vacuuming and recharging is needed, but even then it can be hard to know if (and how much) oil may be needed. I have used the testers but generally had to use several per test, fortunately they are not too expensive.

Also, my experience is to use Nitrogen if ever needed to flush (blow) out a system, just let it blow everything out, pull vacuum, add oil, and then recharge. ~CA

timjet · 09-06-2021, 02:33 PM

OK, I recharged the system. First, I know I have a leak so I don't expect this recharge to last more than a few months. I needed 6.4 lbs, that 8.5 12 oz cans but only added 6 12oz cans, I'm 2.5 cans short. I'll add those cans tomorrow. I left the couplings on the hi and low side and disconnected the hoses. I got a bunch of refrigerant shoot out the high side when I removed the hose from the coupling but it stopped after a second or so. I left the couplings on because they are very hard to connect to the hi and low side due to their locations.

When done the gauges read 25 psi on the low and nearly 150 on the hi side. Not sure what they should be. I noticed when I added the refrigerant the low gauge went up to 60 psi but when the can got empty it dropped to 25.

Air coming out the vents went from 65 deg to 45 deg.

It'll be interesting if it still cools tomorrow before I add the other 2.5 cans.

Unplanned Tourist · 09-07-2021, 07:47 AM

Quote:

Originally Posted by timjet

OK, I recharged the system. First, I know I have a leak so I don't expect this recharge to last more than a few months. I needed 6.4 lbs, that 8.5 12 oz cans but only added 6 12oz cans, I'm 2.5 cans short. I'll add those cans tomorrow. I left the couplings on the hi and low side and disconnected the hoses. I got a bunch of refrigerant shoot out the high side when I removed the hose from the coupling but it stopped after a second or so. I left the couplings on because they are very hard to connect to the hi and low side due to their locations.

When done the gauges read 25 psi on the low and nearly 150 on the hi side. Not sure what they should be. I noticed when I added the refrigerant the low gauge went up to 60 psi but when the can got empty it dropped to 25.

Air coming out the vents went from 65 deg to 45 deg.

It'll be interesting if it still cools tomorrow before I add the other 2.5 cans.

If it's working satisfactorily now, I would hold off on adding more. Those little cans seem to use something a bit different than normal R134 and usually it takes a bit less to get a system running.

If your compressor isn't cycling off and on every few seconds, try it as is. If it is cycling often, then by all means, add more.

timjet · 09-07-2021, 08:20 AM

Thanks Norman, I'll check for compressor cycling and do as you suggest.

rikadoo · 09-07-2021, 09:37 AM

So ac is not a mystery, i agree with some stating shrader vales RARELY leak after being replaced. My opinion is if your wanting to get a handle on this, and DIY IT, then understand you got to know 1. Unless you see oil stains DONT add more oil, 2. Be prepared to think outside the box, by that i mean IF YOU DONT SEE THE DYE WHEN USING THE BLACK LIGHT ITS NOT LEAKING AT THAT LOCATION! 3. When using the black light take off the lowside service cap an look at the shrader valve, cause if THEY DID use dye you will see the color your looking for. 4. If you have looked at all the same places that “everyone” else has, then look somwhere else.
Example: everyone is of the understanding that the “freon sniffer” is the holy grail of ac tools… WRONG! The best tool to use is the one between your ears! I have done ac repairs for a long time, and yes in a perfect world the sniffer works, however it has to be either a major leak OR not a breath of wind. SO, the most negected testing point is the Evaporator, thats the little “core” that sits inside the plenum assembly that blows the air into the cabin. I use a$25.00 borescope that uses wifi to my phone, then i look to where the core sits in the plenum and drill a hole about a inch away from where the core sits an run the probe inside looking to see if it has a “wet spot” if i dont find one then i go to the other side of the core drill another inspection hole an look at that side. That usually shows the problem, once your done looking thru the holes i either use duct tape or dum dum or both to cover them. Another is IF your high side is getting too high (fan clutch not working, or air flow restricted) excess pressure can blow off thru the high pressure safety valve thats usally around the back of compressor, lastly if there no traces of dye then look up, by that i mean if you have a sensor or switch that is at the highest part of a hose or ? It can leak an not leave a dye stain cause dye is not a vapor, it travles with the oil flow, which runs on the lower side of a hose. When that happens its a WAG! (Wild ass guess) usally if I dont find a leak in the evaporator i concider a switch or sensor, (Full disclosure in over 25 years of ac repair i have only had 2 sensors that were in fact leaking)
Honestly though hardly ANY tech i know ever wants to replace an evorator core, so they never look at ways to honestly check one. So they always decide to wave the useless sniffer in the outlets thinking they did there part to check it…
Finall note: if your system uses R-134 the first give away the the evaporator core is leaking, is the amount of dash deodorizers in the vehicle, cause the mixture of pag oil mixed with the freon makes a smell most people dont care for an always are trying to mask the smell, good luck