2002 Chevy Tracker with Aftermarket AC

[Roddy]

Bought tracker new and had aftermarket AC installed. Shop that installed it has gone out of business. So have no information about AC kit. AC installation label has faded completely can just make out 26 or 28 oz of 134a. It worked great for 13 years, now it barely cools at all. Finally got around to taking it to AC shops. None want to work on it because its not factory system and they are unwilling to chase down parts. One shop did put gauges on it and said "low" high side & "high" low side, either the expansion valve is stuck open or compressor has problem. He suggested that if I want to tackle job myself it he will recover refrigerant.
What procedures are used to diagnose problem?
Compressor is Seltec 448-42038 made by Tama in Japan.
Expansion valve and compressor see attachments
Rod

[Tom Greenleaf]

Welcome Roddy: I can understand with the age, obsolete with unknown/unavailable shop that installed it and the reluctance to help out with so much unknown. If you think you can trust the charge amount I would just evacuate the system with it somewhat working now if so and COUNT how much comes out. Being low far more likely than anything else.

Charge back the lesser of what is thought to be correct to see if it can work at all then pressures become more informative.

Not sure just why but some will just snap to from being evacuated and recharged then probably a leak to be found and try to find out how fast via all means.

Then you could decide to go for a fix or just limp it along if slow enough might be just an annual service for this vehicle till you decide to fix it at all or if in superior shape overall might choose another aftermarket whole system still serviceable for the rest of the vehicle's useful life.

Stinks - by nature this could be costly up to out pricing value of the vehicle just for A/C? Where I am with a vehicle this old most people would choose to do without A/C for a short season of any need and just use up the vehicle when it's not needed. Nice if you can just spend a little to find out exactly where you stand with it so you can decide if at all possible,

[Cusser]

It worked great for 13 years, now it barely cools at all.

Roddy - you say it barely cools now, let me assume that the compressor itself engages and turns when AC is on (not just the outer AC clutch pulley). If so, you may be one of the lucky few whose system gradually leaked a tiny bit of R134a per year from the compressor seal, and all that might be needed is a few ounces of refrigerant. So I'd read the pressures at low and high sides at about 1800 rpm, or see if a shop will pull out the refrigerant and weigh it, and then replenish the needed amount.

I will add that I've had that same situation where all that was needed was a few oz. R134a with both my 1998 Frontier and my 2004 Frontier; both have needed additional R134a added exactly once due to natural attrition. The seal is designed/engineered to leak a tiny bit to lubricate the rubber compressor shaft seal.

[Tom Greenleaf]

Love the term "Natural Attrition" Cusser! It's true. If a seal didn't have the very least leak to lube it then it would cook itself. About all found anywhere do that.

Unsaid by the car makers TMK but seen is expect 7 years from new to need some. Hey if that's true this is double that and could write it off as normal for this vehicle.

Hey - my own none less than 20 year olds all original from new known! Describing tweaking by pressures is almost impossible and plan to try to write up an article on how also would apply for systems unknown capacity.

Now you'll more often find shops will first just evac and charge with machines that count to the ounce as said above. If systems known normal and working just weaker it really is just a routine to either learn or ask for IMO for the right shop.

My case have had the same vehicles so dang long know their habits on just this has been stable for about 5 years on each what they do and what to expect.

I also cheat and have a constant thermos in center vent all the time to catch them on time,

T

[Roddy]

Thanks guys. Will purchase manifold guage set and post pressures. Shop said they thought there was enough refrigerant in system. He didn't like pressures...

[Tom Greenleaf]

More than just gauges. It totally matters what fast real temps are plus RPM when checking pressures. Real ambient temp thru grill not forecast temps, raised idle, real center vent performance.

Factor situation of engine is already hot or not, working in full sun or cool shop or shade and cooler outside - all of it matters. Fans matter too.

Your call I like infrared touchless thermos and wired household ones too now hard to find I bought all of them. Those you can watch vent temp while under the hood or string along and place that in front of grille.

You need to learn attitude of touchless thermos practice with your knows, like boiling water, expected body temps, ice and refrigerators or compare with another for same results.

Pressures of refrigerant are incredibly dependent on temps. Know where what temps should be where too not just ports for gauges,

[Cusser]

Thanks guys. Will purchase manifold guage set and post pressures. Shop said they thought there was enough refrigerant in system. He didn't like pressures...

Autozone has free loaner R134a service gauges. I used one just over a month ago when mine were unavailable.

Measure both high side and low side pressures at about 1800 rpm after holding there a couple of minutes. Then mist the condenser with water and see if there are changes.

[Tom Greenleaf]

Yes - Autozone does that in many places - I forgot and don't need to rent. Just a thought though on rented A/C gauges or maybe a pump. You may not know what junk might be in gauges if sealer or something would blow thru a rental set. Vacuum pump just make sure it can pull full vacuum for your altitude if you rent one. FYI @ sea level 29.92Hg and deduct about 1Hg for each 1,000 ft of elevation if much where you are working,

[Cusser]

FYI @ sea level 29.92Hg and deduct about 1Hg for each 1,000 ft of elevation if much where you are working,

Good reminder: the electric vacuum pump I also got on Autozone loan pulled to just more than 25 at the 5000 ft. elevation where I was, and I was aware of that fact. Unfortunately, can't always have all my tools/equipment with me all the time !!!

[Tom Greenleaf]

It's all just noted facts and actually very few % of population lives at an altitude that makes a difference - assorted things like that. I did live in Denver for a year but car had no A/C - was school not for auto anything wasn't involved but noted less power from the car.

Tires even - sea level we live in 14.7 PSI. That in tires changes if ambient air right about 1 PSI / 10F from when checked easy to be 10PSI off it checked hot. There's also known you called it "Natural Attrition" of just air thru rubber brand would matter and age.

A/C anything with some problem as you know it's a real trick to have all live info at once for what to expect. So much matters not always on our minds,

[Cornbinder89]

If it were me, I would recharge with the correct amount and see how it preforms, If there is a problem, you have a base line to start from.
I have pulled apart compressors that have sat for YEARS and they still had oil on the seal. I wouldn't fret about it unless there is a sign of leakage from the seal area.

[Tom Greenleaf]

Without something obvious that's what I would do and take it from there. I'll bet now it will just work out and be done with this.

Don't ask why but some with what I thought was broken just reset itself and worked just doing that - many times and no reason as I really expected a repair but left no reason to mess with it anymore?

[Tom Greenleaf]

Oh - to add to that. With unknown chances of something I'll always use new refrigerant not recovered stuff already had some problems with it once not in a hurry to go thru that again. That was product given to me by a shop that quit doing anything A/C too much trouble and so busy with other things didn't need the headaches,

[Cornbinder89]

An note on the pressure readings. As other have mentioned, check pressures at 1800 RPM. My guess is the shop thru the gauges on at idle. Many after-market AC systems use small compressors and this one is one of them The Tama TM08 is only 5.2 CID and most OEM's are closer to 9-10 CID. Which such a small compressor its not surprising that the high side would be low and the low side high at Idle.
There are two reasons aftermarket tend to the small compressors, 1) they have to fit something on the engine it was not designed to have, and 2) a lot of the aftermarket unit go on small displacement engines that the OEM has decided can't or they didn't want to fit A/C to. By using a small compressor they minimize the load on the engine at idle at the expense of low speed A/C performance.

[Roddy]

Any suggestions on R134 manifold sets? or convert to R134 quick connects?
See lots of knock offs at low prices...
Have Interdynamics R12 manifold from my 1989 F350 that had leaking spring locks that I fixed using oversized O-rings years ago.
Have imperial vacuum pump that still works great.

[Tom Greenleaf]

Roddy: That's a decision you have to make on how much to spend and are you getting what you want for what you paid. I've had many brands best have been and still have RobinAire made or thru Snap-On now with ends and shutoffs via this site so can use on either R-12 or 134a plus R-22 which my home is. Dayton vacuum pump always has behaved can pull full vacuum which is the goal no matter how you achieve that "zero is zero" just know venture pumps can't or don't get there.

Multiple sets two ID sets just one left working other for parts and a super cheap Quest set gone now just save hoses was total junk needed in an hour - just give me some readings a hose again failed.

Then you may want to double the whole expense making up connections so you can have super long hoses going end to end. Hose end plugs if your set doesn't park them AND seal you or I'll say I made up plugs to vacuum out hoses/manifold set so it's clear of any other vapor or refrigerant.

If up to it and willing to invest you should have 2 of everything! One set may not connect or may have an attitude with fittings so you have the other. Include right angle ends as sometimes there's just no room otherwise.

Stuff can easily be dropped and bust gauge dials, hoses can just not seal by surprise and so on.

Not done yet - have to have credible thermometers that are fast matters. Two are touchless infrared like those for assorted reasons. On hand "O" ring sets. The full assortment of flare nut wrenches, sprays, dye and more. Love a now old Matco sniffer that likes lithium batteries for tougher leak finding. Spare caps for both R-12 and 134a Acme.

The next is the full compliment of volt/ohm meters, jumper wire fused or not at the ready and like pure silicone grease by only one found is Dynatex for O rings and anything threaded. Mirrors of all sorts and an assortment of corded and cordless lighting.

The miscellaneous stuff out costs just the primary set of gauges 10 times or more all depends on what you want to be able to do.

#1 expense is the place to work always. That means if you really want to or need to work in any weather must be able to heat it off season along with equipment and refrigerant. This is inland New England can easily be below zero F. windy and room plus the time to heat it all would like to start at 100F with time for vehicle and all assorted tools in shop to heat up takes forever for those rare times almost always a body shop done with fixing a small accident that took out condenser and needs it charged and checked that it will work can't be known if not hot enough. Those the vehicle is done except for that just leave it in a state of vacuum please.

Recovery is left to area shops I don't want the used product I'll always use new virgin product/refrigerant. An assortment of scales on hand too.

Nobody I know of locally has the room or time that all takes or put all equipment away off season. More often just don't do any of it as said above there's enough to fix in general year round all the stuff for A/C isn't worth the space or expense.

So search out what you want but at least gauges I'd have two sets keeping what you have just buy the adaptor ends and another just for 134a. All the rest decide on how much you wish to invest for stuff you may not use for ages.

Quality counts but only to a point - anything can break or let you down just when you need it. If you can't spend some time and have other things to do it's impractical for most where I am for most as said it's highly seasonal where I am just because you can't know if a system works at all if cold out for several months you wouldn't even know it wasn't working never mind properly.

All depends on you pain tolerance for the costs, available space and your time to do it plus if real difficult the code readers and scanners if not a refrigerant side plain problem at all and paid software to keep that current or send that part out if monthly costs can't be worth it,

[Cornbinder89]

Hoses, go for quality, a bust hose can blind or freeze you. Manifold, if what you have works, then lhat's good enough. Convertor quick connects for automotive 134a again, I go quality. Since I also dabble in non-automotive I have a separate set of hoses with 1/4 turn ball valve ends for that.
Robin-air, Snap-on, MAC, Master-cool all are good stuff.
Never felt the need for 4 port manifolds, just swap the center from vacuum to charge tank. You can spend silly amounts of money to do what a modest amount will do just as well.
Gauge heads are replaceable, so if you have a bad gauge on a good manifold, it is not a reason to change manifolds.