keihin a/c compressor, A/C problems

[zenapup]

I am the second owner of an 88 LX-i and it was retrofitted to R134a by the first owner. It also has a Keihin compressor. It was recharged last April and was not as cool as I thought it should be. I also replaced the compressor at that time with a used Keihin because the original Keihin's front seal was bad. I also replaced the o-rings on the hoses going to the compressor just to be safe. While doing this, I had the system open for about 2 hours. About a month ago, we started using the A/C again, and it was noticeably weak. Recently, it has started blowing the #5 fuse in the underdash fusebox everytime I turn the A/C on. If I disconnect the compressor clutch connector from the compressor lead, the fuse no longer blows. Given this information, I have a few questions

1. Do I HAVE to replace the receiver-dryer (about $60 for an OEM)
2. Is my compressor clutch faulty, or is the dryer shot from being exposed to the atmosphere for 2 hours.
3. Why does the fuse keep blowing?
4. It there a cheap way to retrofit to a Denso compressor (under $100) and would I get better results from it.
5. Do you think that there is a leak in the system somewhere? If so, where?

Any advice/help is greatly appreciated
Sorry if my post is a little long, I just prefer to give all of the details to get better solutions

[ecogabriel]

Keihin compressors ARE NOT recommended to be retroffited to r-134. Not sure about the cause, but I believe its seals are not compatible with r-134.
Search for info in the EPA website; there is a list there, and the Keihin in 86-89 accords appears as NOT suitable for retrofit.
Denso compressors can be retrofitted; search for the right procedure.

FYI, I have seen a few 3Gs with SANDEN compressors in the JY. However, I could not see what model it was or the kind of bracket it used.

You can install a Denso compressor in your car provided you get the hoses and bracket that goes with it; I dunno whether there is something else that is also needed. A new retrofit kit would run about $600 I believe.

https://www.3geez.com/forum/showthread.php?t=77475

[DBMaster]

Yes, do replace the receiver/drier. I got mine last time on Rock Auto, Four Seasons brand. It was about $30. It filters refrigerant and has a desiccant bag to capture any stray moisture. Very cheap insurance. The thing with the Keihin is the "Viton" shaft seal. I'm not sure if it's the refrigerant (R143a) or the different type of oil used with it, but it eventually causes the shaft seal to leak on the Keihin. I retrofitted mine to a Denso in 1999 and that compressor lasted until 2010. Brand new Denso compressors are $300 on Rock Auto.

[zenapup]

@ecogabriel As I said, when I bought the car, it had a Keihin compressor and had already been retrofitted. I myself would have left it on R12.

@DBMaster Why did your compressor end up failing in 2010?

I only need a Denso compressor and its mounting bracket as well as a new receiver-dryer, correct?

[zenapup]

I don't think my compressor seal is leaking currently, but when I try to turn on the A/C, the clutch engages, and then the #5 fuse blows immediately, so I think it might be an electrical problem.

[zenapup]

Yes, do replace the receiver/drier. I got mine last time on Rock Auto, Four Seasons brand. It was about $30. It filters refrigerant and has a desiccant bag to capture any stray moisture. Very cheap insurance. The thing with the Keihin is the "Viton" shaft seal. I'm not sure if it's the refrigerant (R143a) or the different type of oil used with it, but it eventually causes the shaft seal to leak on the Keihin. I retrofitted mine to a Denso in 1999 and that compressor lasted until 2010. Brand new Denso compressors are $300 on Rock Auto.

Could I just replace the shaft seal when it goes bad? I can still get it from Honda

[zenapup]

Keihin compressors ARE NOT recommended to be retroffited to r-134. Not sure about the cause, but I believe its seals are not compatible with r-134.
Search for info in the EPA website; there is a list there, and the Keihin in 86-89 accords appears as NOT suitable for retrofit.
Denso compressors can be retrofitted; search for the right procedure.

FYI, I have seen a few 3Gs with SANDEN compressors in the JY. However, I could not see what model it was or the kind of bracket it used.

You can install a Denso compressor in your car provided you get the hoses and bracket that goes with it; I dunno whether there is something else that is also needed. A new retrofit kit would run about $600 I believe.

I believe that retrofit kit is to convert the system to R134a, I just need to make the compressor compatible to make it good for R134a, which it already has

[lostforawhile]

I believe that retrofit kit is to convert the system to R134a, I just need to make the compressor compatible to make it good for R134a, which it already has

if you are good, you could look for another compressor off a car with the right direction engine rotation and swap them out, there are companies that make adapters to hook the hoses up, or you can have custom hoses done, the compressor mounting is very basic

[gp02a0083]

@ecogabriel As I said, when I bought the car, it had a Keihin compressor and had already been retrofitted. I myself would have left it on R12.

@DBMaster Why did your compressor end up failing in 2010?

I only need a Denso compressor and its mounting bracket as well as a new receiver-dryer, correct?

Make sure you get the upper manifold for the A/c compressor, when you buy a new Denso it may not have it. Take the high and low pressure lines as well.
Putting R-134 in the kiehin compressor will just buy you time until it fails. It was never designed for the retrofit, you better off replacing it with a denso. I did the conversion a year ago to my 89 lxi, never had a problem since then.

I looked at the circuit diagram regarding your issue with the #5 fuse being fried. That fuse leads with a yellow/black wire to the compressor clutch relay and a red wire to the compressor clutch and ground. So it narrows it down to the relay and the compressor clutch being bad even tho you may see the compressor engage it may be likely that its drawing too much current somehow and frying the fuse. The only other place the compressor clutch relay is connected to is the ECU, but i am thinking is the compressor clutch.

[Dr_Snooz]

It is recommended to replace the drier each time you open the system. However, if you pump the system down for a couple hours it will draw the moisture out of the dessicant for you. I only replace driers now when I've had the system open for a long time and am worried about potential dirt contamination.

You haven't already put gauges on it, so I'm going to assume that you are a relative newb to A/C work. If you are worried about leaks, put gauges on it. That will tell you if you have a leak.

The Keihin compressors are not very good, as a rule. New compressors are expensive, however, so unless you verify that the compressor is bad, keep it.

You don't mention where you got the rebuilt compressor, so its possible the clutch is bad. Is it making noise?

[lostforawhile]

you will do better to go to the denso and do the retrofit,simply for the sake of it's getting impossible to find R12,

[nswst8]

I ran a keihin compressor with R134a for a number of years in Florida and Conneticut, Texas was just to dam hot for R13a/Keihin compressor so I took it back to R12.

Keihin/R134a needed a maintenence charge about 1-2 times per year. I had a temp gauge in the center vent. As long as I was getting 20-30 degree temp different from the outside temp I was good. Anything less than 10-15 degrees different I would charge it.

When I swapped it to R12 I bought a denso unit. R12 is still available I get mine through Ebay I challenged the EPA609 online It cost $25. 25 questions open book and I am not an A/C technician. I have like 50lbs of R12.

I have a Sanden retrofit compressor set up I bought just in case I couldn't locate a Denso retrofit kit. I paid $397 I'll let it go for $275 shipped.

I am very happy with the Denso retrofit set up but they are difficult to locate.

The receiver/drier doesn't need to be replaced everytime the system is open, only when you don't know how long the system has been fully depleted.

Sounds like your compressor is creating to much electrical draw engaged, I'm thinking it's a bad compressor.

Good luck

[2drSE-i]

Here's what you need from the junkyard:

Denso compressor bracket and hardware ~$20
Denso compressor manifold Cheap
Denso High and Low side hoses Cheap
Dryer/reciever ~$30
Expansion Valve ~$20


YES, you absolutely need a new dryer. Without it, your A/C system will not work NEARLY as well as it should. The expansion valve is a good idea, simply because they tend to fail alongside the compressors. And its a 23 year old part at this point, chances are it's bad.

[gp02a0083]

you will be hard pressed to find the upper manifold for the Denso, i could not source one anywhere online at all. I went back to the junkyard.

the expansion valve is a good thing to point out 2drse-i, they can fail. However likely hood that they will fail is less than a compressor or clutch failure unless you got some serious garbage in the AC system due to a pump failure. I strongly emphasize getting a new dryer, there cheap and when evacuating the system and replacing the compressor this is a standard procedure.

pumping down the A\c system with a vac pump will help out a great deal being that you will have a minimal amount of contaminants and you will be able to properly charge the system. If you don't believe me i will bet my hatchback that an A/C system will work top notch with a new drier and properly evacuated system.

Nswst8, i have hard stories where individuals kept the junk compressor and retrofitted it with the R134 and have had long term success with it. about 70% of the posts you can search on the forum say they had pump failures within 2 years or less. You shouldn't have to service the A/c system that frequently, its a closed system. I would bet you have a tiny leak somewhere , most likely caused by a dried out o-ring

the Saden works well too but best bet is going with the denso

get the high and low pressure lines, the compressor bracket, the top manifold on the compressor from a junkyard and buy a rebuilt compressor and a new dryer and you should be set. This conversion is relatively simple, took me an afternoon to retrofit it.

[zenapup]

I ran a keihin compressor with R134a for a number of years in Florida and Conneticut, Texas was just to dam hot for R13a/Keihin compressor so I took it back to R12.

Keihin/R134a needed a maintenence charge about 1-2 times per year. I had a temp gauge in the center vent. As long as I was getting 20-30 degree temp different from the outside temp I was good. Anything less than 10-15 degrees different I would charge it.

When I swapped it to R12 I bought a denso unit. R12 is still available I get mine through Ebay I challenged the EPA609 online It cost $25. 25 questions open book and I am not an A/C technician. I have like 50lbs of R12.

I have a Sanden retrofit compressor set up I bought just in case I couldn't locate a Denso retrofit kit. I paid $397 I'll let it go for $275 shipped.

I am very happy with the Denso retrofit set up but they are difficult to locate.

The receiver/drier doesn't need to be replaced everytime the system is open, only when you don't know how long the system has been fully depleted.

Sounds like your compressor is creating to much electrical draw engaged, I'm thinking it's a bad compressor.

Good luck

What exactly is included in that Sanden retrofit kit? Also, it's for a R134a system, correct?

Also could someone post pictures showing the difference between the Keihin and Denso compressor

[DBMaster]

@ecogabriel
@DBMaster Why did your compressor end up failing in 2010?

The compressor clutch actually burned up - literally. Something shorted and I saw smoke coming from under the hood. The insulation burned off the wires as well.

Here's my observation about compressors. Ever since the late 70's when cars started having compressors that cycle on and off the clutches wear out before the rest of the thing. When they wear out they often seem to damage the main seal as well. Mine lasted 11 years and I like it cool so I probably use the A/C on days when other people wouldn't. The thing made several different unpleasant noises for years before it went out. In fact, the one I have now from 2010 is not all that quiet when it is engaged. It concerns me, but there's not much I can do about it. It works well. It has Freeze 12 in it which is basically 80% R134a with 20% of another refrigerant that carries the mineral oil through the system.

[nswst8]

What exactly is included in that Sanden retrofit kit? Also, it's for a R134a system, correct?

Also could someone post pictures showing the difference between the Keihin and Denso compressor

The Sanden kit comes with all the mounting hardware needed to install and yes it is for R134a. Bought it off ebay from a A/C outfit in Texas. Very friendly guys. (Brackets and bolts)

The keihin conpressor looks somewhat like an airplaine engine with the cylinders surrounding the compressor.

[nswst8]

[QUOTE=gp02a0083;1090682]

Nswst8, i have hard stories where individuals kept the junk compressor and retrofitted it with the R134 and have had long term success with it. about 70% of the posts you can search on the forum say they had pump failures within 2 years or less. You shouldn't have to service the A/c system that frequently, its a closed system. I would bet you have a tiny leak somewhere , most likely caused by a dried out o-ring

QUOTE]

Your right I had a small leak at the expansion valve and compressor suction side. I retrofitted the keihin in 1997 and I swaped it in 2007/8 while we we're stationed in San antonio, TX. Texas was just too much for a R134a retrofitted well aged Keihin.

[nswst8]

Basic Charging Procedures
REFRIGERANT CHARGING PROCEDURE IN AUTOMOTIVE A/C SYSTEMS

We recommend reading this procedure completely before charging. You may need information before charging you want to keep handy. Have this procedure with you while charging. Although it can be done by a single person, we recommend having a helper around.

This procedure outlines the steps to perform a complete charge. These steps are not to be used to refill or make partial charges. Toping off requires system parameters monitoring and knowledge, specially in R134a-based system. Excessive gas will harm your system and will keep it from cooling properly. MORE REFRIGERANT DOES NOT MEAN COLDER TEMPERATURES

CHARGING IN GAS OR LIQUID - Please read step 10

Do not use the sightglass (if so equipped) in R134a-based systems as if were R-12 based.

SPECIAL EQUIPMENT REQUIRED

1) Vacuum pump

2) Gauges (R12 or R134a)

3) Service port adapter (as required in most R12-based systems) R134a systems do not require adapters other than the couplers in your gauges in the majority of applications

4) Refrigerant gas (R12 or R134a)

5) Optional: 2-3 ounces of specified oil.

**************

1. Make sure what is the required amount of gas. From factory, all systems have a decal under the hood that give the data. If the decal is missing or you are not sure, please specify make, model, and the type of refrigerant used and whether your system is a factory or an after market unit here. It is very important to know if your system has oil. Oil starvation is the main reason of compressor failure. Oil can be added to the system in two ways: with oil injectors or through the low side port under vacuum. The procedure to add oil through vacuum is described here. Some refrigerant charge and other useful specifications are provided here.

2. Connect both blue and red gauge hoses to the system's service ports. The discharge port (red hose) is located somewhere between the compressor and expansion device, either before the condenser or after it. In R134a systems, the port is the thicker of both, while in R12 systems is the thinner one. In some aftermarket systems, the port is located in the back of the compressor. If your ports are located in the compressor, the low side is marked by an "S" and the high side by an "H". Port caps have an "L" for low or "H" for high.

3. Open both gauge valves. Connect the common hose (yellow one) to the vacuum pump. Make sure both gauge needles are zeroed down. Needle is adjusted by turning a fine screw inside the dial. You must remove the plastic lens to do this.

4. Turn the pump on. You'll notice that both gauge readings begin to drop. The blue gauge's needle will even dip into negative values. The desired low side reading should be less than -25, while the high side will remain at 0.

5. After approximately 5 minutes, close both gauge valves. Turn the pump off, and observe the needles. Any movement will indicate vacuum loss. The faster the movement, the greater the loss. If after two minutes you don't see any needle movement, open both valves, turn the pump on, and continue vacuum for not less than 30 minutes. Close both valves then turn the pump off.

6. Get ready to charge. Have the necessary refrigerant amount handy. Cans make charging easier and more precise unless you have a charging cylinder or a precision scale.

7. Disconnect the yellow hose from the vacuum pump and connect it to the can tap or charging cylinder valve. You can charge in two ways: liquid (can upside down) or gas. Liquid charging is a lot faster but not recommended unless you extreme care or have experience. Traditional (gas) charging is slower but safer.

8. Once you've decided, and with the can or container connected, unscrew the top yellow hose connection (at the gauges) allowing refrigerant to escape for a couple of seconds. This will purge the air out of the hoses so you make sure that all you dispense is refrigerant. You can do this venting in liquid form so you can see when a fine, steady stream of refrigerant escapes indicating that all the air is gone from the hose. Don't breathe refrigerant and don't charge in a flammable environment.

9. "Flood" the system with liquid refrigerant (can upside down) by opening the red valve (high side) until it won't take anymore. Close the red valve. Jump the low pressure cycling switch (if so equipped). If you don't know what this is or where it is, ask for help here.

10. Turn the engine on. Turn the A/C into MAX on its third or higher blower speed. You'll note that both gauge readings are now positive. The red gauge should read between 100 and 150, while the blue gauge between 5 and 15. If you are charging with cans, don't forget to purge air out the hose after hooking a new can as described in step 8 above. Now, charge will continue through the low (blue) side (see note below) . If you haven't jumpered any switch (you don't have to), you'll notice the compressor cycling frequently on and off. That is normal. The cycling will disappear as you dispense more refrigerant. The only disadvantage of frequent compressor cycling is that charge will take longer. Needles will move up and down with every cycle. This is normal. Do not jump any switch unless you are absolutely certain!.

WARNING: DANGER

NEVER OPEN THE RED VALVE WHILE CHARGING. The red valve is to be opened only during pre-charge, vacuum, or when a system is evacuated. Its function is keeping an eye on the high side only. It must be closed at all times. If you have any doubts, wait until you receive information. Severe injury or death may occur. Remember: ALWAYS wear safety goggles. NEVER charge your system in a closed environment.

GAS OR LIQUID CHARGING?

There are two ways to charge: gas (can or cylinder up), or liquid (can or cylinder upside down). A compressor is designed to compress gas. Direct liquid charge will harm the compressor if suction pressure is not controlled. Liquid charging is faster, yet is riskier. Liquid charging should be made by professionals or under supervision. Liquid charging can be done if the suction port is away from the compressor (some compressors have the suction valve in its body).

Liquid charging can be done never exceeding a 50 PSI suction pressure. If you can't control it, charge in gas form. In cooler weather, cans may freeze. You may immerse them in water and shake them while charging.

11. Once about 2/3 of the charge has been dispensed into the system, spray water in the condenser to optimize heat exchange and speed the process. When you get the condenser wet, vent temperature is likely to raise. This is normal. You'll also note pressure drop in both gauges.

12. Once the specified amount has been dispensed, close the blue valve. Let the system run for a minute. Turn the A/C off and then the engine. Wait another minute and disconnect the couplers from the service ports. Disconnect the low side first. If you jumpered a switch, reconnect it too.

Optimum cooling performance is attained after 10 minutes of operation. Our own acceptance criteria is at least 50°F in the center vent to the driver side at idle after 10 minutes or less. Remember: cooling increases while the vehicle is in motion.

VERY IMPORTANT

Due to the physical properties and chemical composition, R134a and R12 charging amounts are different. Never, if you are retrofitting, charge the same or specified amount of R12 with R134a. If in doubt, please e-mail us here. Do not use this procedure if you are using any other refrigerant. This is just for R12 or R134a. Although procedures and parameters may be similar, we do not use nor recommend alternative refrigerants.

HOW TO DETERMINE OPERATING PRESSURES

Every vehicle has its own operation parameters specification. Depending on whether or not the vehicle has a factory or an after market system, and whether it was retrofitted or is still original, among others. There is no established calculation to determine the exact operating pressures.

The low pressure (blue gauge) should be 35 or less at idle, regardless of the type of gas. Only if you're running a dual system, the low pressure may be between 45 and 50 at idle.

The high pressure, for starters, is directly related to ambient temperature: the higher the temperature, the higher the higher the pressure.

Bear in mind that dispensing a complete charge without lowering the pressures with water will result in higher readings. This is normal, and that is why you should spray water in the condenser at 2/3rds of the charge or once you have completed it. You'll note an immediate pressure drop when you spray water in the condenser.

To obtain a ballpark high side value, multiply ambient temperature by 2.2 if you have an R12 system. If you have a factory R134a system, use 2.3. To convert °C to °F, use this formula: °C X 1.8 + 32.

Remember: this is only a ballpark. If in doubt, we have factory charts to help you determine the correct pressures. Please have your vehicle's make, model, refrigerant type, and year and click here.

Factors like a an obstructed or very dirty radiator and condenser, weak or inoperative fan clutch, weak or inoperative radiator fan(s), either electric or mechanical, will make pressures go up and impair cooling, even in mild days.

[zenapup]

The Sanden kit comes with all the mounting hardware needed to install and yes it is for R134a. Bought it off ebay from a A/C outfit in Texas. Very friendly guys. (Brackets and bolts)

So, the suction and discharge hoses for the keihin and sanden are the same and do not need to be modified, correct? Im assuming the belt is also the same, correct?

[lostforawhile]

if you need the keihin compressor clutch, I have the entire unit sitting in storage, I'm not sure if the compressor works but the clutch is good, I could send you the entire unit, or I could wait and rent the tool next week to pull the clutch, I don't want anything for it, just the shipping.

[lostforawhile]

So, the suction and discharge hoses for the keihin and sanden are the same and do not need to be modified, correct? Im assuming the belt is also the same, correct?

if you can't find the hoses or can only find bad ones, lots of hydraulic hose shops can make you a new line using your ends

[zenapup]

if you need the keihin compressor clutch, I have the entire unit sitting in storage, I'm not sure if the compressor works but the clutch is good, I could send you the entire unit, or I could wait and rent the tool next week to pull the clutch, I don't want anything for it, just the shipping.

What would shipping cost me for the entire compressor?

[lostforawhile]

What would shipping cost me for the entire compressor?

I need your zip code and then I can weigh it and get you a price

[gp02a0083]

The compressor clutch actually burned up - literally. Something shorted and I saw smoke coming from under the hood. The insulation burned off the wires as well.

Here's my observation about compressors. Ever since the late 70's when cars started having compressors that cycle on and off the clutches wear out before the rest of the thing. When they wear out they often seem to damage the main seal as well. Mine lasted 11 years and I like it cool so I probably use the A/C on days when other people wouldn't. The thing made several different unpleasant noises for years before it went out. In fact, the one I have now from 2010 is not all that quiet when it is engaged. It concerns me, but there's not much I can do about it. It works well. It has Freeze 12 in it which is basically 80% R134a with 20% of another refrigerant that carries the mineral oil through the system.

DB, think about it, it does seem odd to an extent why a main seal would fail. Your engine is running at higher than idle speeds and if the clutch is cycling often, the torque applied at that instant is quit a bit. I think with your newer compressor might have been rebuilt wrong or there is a high possibility of the old compressor veins failing and being thrown into other areas of the A/C system.

NSWST8, i like the post you have about the recharging procedures, its very important that you make sure you connecting the hoses to the high pressure side. Ive seen many wanna-be's get hurt during this process. I think that posting you have should have a section where it is stickied