Anyone overhauled the AC compressor

[My98RT10]

When I was doing my TC gasket repair, I noticed, that my AC compressor developed a leak as well, so my next project seems to be on the way...LOL. I know, that the O-rings are common to fail over time. However, in my case the shaft seal seems more to be the culprit.

I have checked the forums but could not find and How-To on the compressor overhaul. Anyone here done this? I'd like to try it before purchasing a new one....

Thanks!

[ssmith71]

Good question, I think mine has a leak as well as I am loosing Freon but I can't find from where, so I am guessing its the compressor.

[LifeIsGood]

I'm also interested in a possible compressor replacement.

[Joel]

Just get a new or rebuilt compressor. You can't buy the parts or rebuild one for the price you can get a new or rebuilt guaranteed part. If you just want to play with it, go to a junkyard and get an old compressor. Take it apart and you'll see what I mean. Get a dye kit and see where your unit is leaking before you do anything.

[My98RT10]

You can get a reseal kit for 25 bucks. If this all it needs to get it into good shape again then I am sold :)

[AZTVR]

There are tutorials on Youtube for Denso AC compressor reseal. I'm not positive that is what is on a Gen 2, though.

[My98RT10]

There are tutorials on Youtube for Denso AC compressor reseal. I'm not positive that is what is on a Gen 2, though.

My shop manual says it's a Denso 10PA15C, which seems to be a commonly used model in various makes.

@Boosted: any plans to do a video on this? :anonymous:

[My98RT10]

So I kicked this off by ordering the parts. I have almost everything, except a small tool which makes the difference between victory or defeat: a lip seal protector, needed to properly install the compressor shaft seal. I had to order it in the US as I could not find it here....

The plan is to replace all seals/gaskets plus the drier.

Here's what I got so far:

A/C O-ring assortment

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0175_zpsflmzkhv6.jpg

Seal kit for Denso 10PA15C compressor

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0179_zpsxr96ygfo.jpg

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0180_zpsvxmqyld2.jpg

Compressor shaft seal

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0184_zpsrqb8e8cg.jpg

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0183_zpsxl8hpouc.jpg

New drier

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0177_zpshkywrfoa.jpg

As soon as I have received the lip seal protector I will go ahead and get the refrigerant removed and start the job.

[My98RT10]

This is odd... but maybe someone can help to clarify!?

I was reading the shop manual regarding the amount of refrigerant oil I would have to add to the compressor when having completed the overhaul and put the compressor back in. On page 24-5 of the manual there's the following table:

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/Refrigerant%20Oil%20Capacity_zpsh7ekcvtf.jpg

But how come that if you add up the single amounts the sum exceeds the total amount stated in the first line (140ml)? I don't really understand what they mean by "Line blown", maybe I am just missing something..!?

In any case, as I plan to replace the drier, I would have to add 30 ml of ND8 PAG oil, plus the amount I drain from the compressor before disassembly. Does this makes sense?

[lmn]

The individual amounts would be what you would add to the system if you were replacing the corresponding component only. When the system runs the oil circulates and "accumulates" unevenly inside the different components, that is the reason the individual amounts add up to more than the system total. You might want to consider using Nylog Blue or an equivalent when reassembling the components.

[mblgjr]

Curious if the compressor drops out from the bottom/fairly straightforward?

I'd looked once & debated if maybe would need to pull 1 motor mount loose to rock the engine over a bit.

[71firebird400]

Curious if the compressor drops out from the bottom/fairly straightforward?

I'd looked once & debated if maybe would need to pull 1 motor mount loose to rock the engine over a bit.

There is no mention of additional work being necessary in the FSM- might just be a tight fit.

[AZTVR]

Curious if the compressor drops out from the bottom/fairly straightforward?

I'd looked once & debated if maybe would need to pull 1 motor mount loose to rock the engine over a bit.

I replaced mine on a Gen 2. I can't remember if it came out from the top or bottom; so, it probably was no big deal since it didn't stick in my memory.

[My98RT10]

Looking at it I would think it comes out from the bottom rather than from the top.

[My98RT10]

The individual amounts would be what you would add to the system if you were replacing the corresponding component only. When the system runs the oil circulates and "accumulates" unevenly inside the different components, that is the reason the individual amounts add up to more than the system total. You might want to consider using Nylog Blue or an equivalent when reassembling the components.

Thanks for the explanation regarding the oil capacities. I have yet to find a place that sells something like Nylog Blue here...

[Boosted Motorsports]

My shop manual says it's a Denso 10PA15C, which seems to be a commonly used model in various makes.

@Boosted: any plans to do a video on this? :anonymous:

Haha not yet? Maybe if someone comes out with an upgrade kit? :lol2:

My AC blows cold as possible for a Viper so hopefully no overhaul for me soon! Keep us posted on how it goes though!!!

[My98RT10]

Haha not yet? Maybe if someone comes out with an upgrade kit? :lol2:

My AC blows cold as possible for a Viper so hopefully no overhaul for me soon! Keep us posted on how it goes though!!!

Will do! But I will not do a video, I'll leave that to the master expert :cool:

[OK Falls GTS]

I can fix just about anything but decided to replace the compressor instead of fixing it. Got the barnd new [ not rebuilt ] Denso compressor from Rockauto for about $200 US. To remove the compressor, i recommend to remove the P/S pump from the bracket and push it on the side. The compressor will come out easier on top than from under.Got it done just in time for our hot weather here in the Okanagan.

[My98RT10]

I can fix just about anything but decided to replace the compressor instead of fixing it. Got the barnd new [ not rebuilt ] Denso compressor from Rockauto for about $200 US. To remove the compressor, i recommend to remove the P/S pump from the bracket and push it on the side. The compressor will come out easier on top than from under.Got it done just in time for our hot weather here in the Okanagan.

Thanks for the tips on the removal of the compressor! 200 bucks for a new compressor is quite a good deal I think. I like to fix things if possible instead of replacing them, especially if there's a business case (seals and tool will sum up to 50 bucks). So I hope it will be good for another 20 years then ;)

[OK Falls GTS]

$210.79 to be exact. part number; DEN 471-0355 from Rockauto, shipped from Azusa, CA. Brand new made in Japan.

[Matt M, Pa]

This is a great thread, thank you! I always assumed that the compressor was used on other vehicles...like the starter...but never would've thought to check Rock Auto.

Off topic. When the starter acted up in our 1996 RT, the local alternator shop rebuilt the original with same day service as the parts were common.

[My98RT10]

I have received the lip seal protector so I will tackle this now. Tomorrow I will get the system drained and let's see, how far I come over the weekend. Will post my progress here...

[bluesrt]

better hope the clutch isn't seized to the front shaft that you have to pull with a puller I suppose/ most do, a lot of times also if the case is aluminum,they leak at the body also

[My98RT10]

Today I was at the shop draining the refrigerant. It measured around 750 grams removed so not very much got lost (factory charge is 822 grams) and 13 ml of oil was drained.

Now as for the oil:

My Denso compressor uses ND-8 PAG oil according to the label. I got myself a small bottle of PAG 46 which is the equivalent with the same viscosity. Basically to lube the new o-rings and seal prior to installation. The original ND-8 is hard to get here and much!! more expensive.

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0197_zpszwcddmbd.jpg

Here's a pic of the lip seal protector:

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0202_zpszfbfc6tv.jpg

Tomorrow I will start to tear the A/C apart... ;-)

[My98RT10]

Yesterday, I removed the compressor. I tried to remove it from the top after unbolting the steering pump and moving it aside. No luck. I tried to remove it from the bottom, no luck either. Finally, I removed the steering pump from the vehicle and got the compressor out from the top. The shop manual does not provide any info as to what the "official" way of removal is... would be curious if anyone had been able to remove it from the bottom without removing other stuff first....?

Pump just unbolted, but not enough room to get the compressor out:

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0206_zpshvuujql9.jpg

Pump removed, looks much better now:

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0208_zpsiwk95tua.jpg

Compressor removed, now the fun begins. As a side note: the compressor might not look like a leaky one but during my TC gasket repair I gave everything a wipe down, also the compressor. It was covered with green mist for the most part at the time. Also there was quite some green moisture around the clutch plate, almost dripping to the ground. I have not use the A/C since then...

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0214_zpsn0hrdhcx.jpg

[Coloviper]

Great thread! This is probably on my list as well since my A/C struggles to be cold now and also I need to change the seals on the whole system. Change the pulleys on everything to IPSCO, etc. it just means a bunch of stuff when you get in there. Ha! Ha!

However does anyone have a diagram of the specific o'ring areas on the A/C system and sizes of the o'rings? As well has anyone created a spreadsheet table of all the parts needed and the specific part numbers for each part of the A/C system? Sorry I am an engineer and can only seem to function in spreadsheets these days. Ha! Ha!

[OK Falls GTS]

[QUOTE=My98RT10;303125]Yesterday, I removed the compressor. I tried to remove it from the top after unbolting the steering pump and moving it aside. No luck. I tried to remove it from the bottom, no luck either. Finally, I removed the steering pump from the vehicle and got the compressor out from the top. The shop manual does not provide any info as to what the "official" way of removal is... would be curious if anyone had been able to remove it from the bottom without removing other stuff first....?

Pump just unbolted, but not enough room to get the compressor out:

The pump comes out to through top but you have to turn it around with pulley facing upwards. Many exotics are this way, you got to find the right orientation to deal with.Did you remove the p/s pump pressure side hose connector and put the p/s pump past the aluminum cross member? I also remove the airbox and hoses attached to it. More room the better.


Pump removed, looks much better now:

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0208_zpsiwk95tua.jpg

[My98RT10]

I only unbolted the pump with the hoses attached. This way I could not move it enough to whatever side so that I could get the compressor out. Instead of trying for an hour or so I thought I would be quicker when just disconnecting the pump completely and remove it. Unbolting it took quite some time already.... I did not remove the air box, just the smooth tube. But thanks for the tips!

[My98RT10]

Great thread! This is probably on my list as well since my A/C struggles to be cold now and also I need to change the seals on the whole system. Change the pulleys on everything to IPSCO, etc. it just means a bunch of stuff when you get in there. Ha! Ha!

However does anyone have a diagram of the specific o'ring areas on the A/C system and sizes of the o'rings? As well has anyone created a spreadsheet table of all the parts needed and the specific part numbers for each part of the A/C system? Sorry I am an engineer and can only seem to function in spreadsheets these days. Ha! Ha!

I will certainly post the o-ring sizes I have used, so stay tuned! In general, AFAIK, there are 2 o-rings for the compressor lines, 2 for the lines at the condensor and another 2 at the drier. In addition, there are the o-rings for the compressor itself, which you only need if you disassemble the compressor (like I did). For this you need to buy a seal kit, see one of the pictures in this thread.

[My98RT10]

better hope the clutch isn't seized to the front shaft that you have to pull with a puller I suppose/ most do, a lot of times also if the case is aluminum,they leak at the body also

Had no issues removing the clutch. Once I unbolted the shaft screw I could remove everything by hand, no puller needed.

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0217_zpslkr7pbex.jpg

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0226_zpsa0faickx.jpg

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0227_zpsut7jupyg.jpg

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0228_zps1obowmbn.jpg

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0235_zpsx51piixw.jpg

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0239_zpstcvusc6x.jpg

[ssmith71]

I will certainly post the o-ring sizes I have used, so stay tuned! In general, AFAIK, there are 2 o-rings for the compressor lines, 2 for the lines at the condensor and another 2 at the drier. In addition, there are the o-rings for the compressor itself, which you only need if you disassemble the compressor (like I did). For this you need to buy a seal kit, see one of the pictures in this thread.

Don't forget to replace the schrader valves also as they may leak too.

[My98RT10]

Don't forget to replace the schrader valves also as they may leak too.

Did that already :)

[My98RT10]

Here are now the dimensions of the o-rings I used so far:

Compressor (2 different sizes):
9/16" x 3/32"
7/16" x 3/32"

Condensator (both connections same size):
2 x 7/16" x 3/32"

Drier to follow...

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0308_zpsya1jp9eu.jpg

Black=old, green=new... the new ones are a little thicker but went in fine...

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0301_zpskwtsfwve.jpg

[My98RT10]

Today I replaced the o-rings at the condensator... what a PITA... had to remove the front fascia and some more parts to get finally access to the fittings... they are pretty well hidden! Sorry that I don't have pictures from every single step, I was very busy figuring out what to remove and how that I forgot about it...

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0314_zpsivwcei84.jpg

After removing that black plastic cover panel in the middle I had to unbold the next plastic covers, left and right (these are actually held in place by push pins) so I could move them out of the way. Now, I could get access to the bolt of the fitting(s).

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0321_zpsfzczfodu.jpg

Fitting on driver's side

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0324_zpscrivx1y1.jpg

Fitting on passenger's side (under the hood latch)

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0329_zpsm1m9qfwu.jpg

I replaced the o-rings and will pray now, that everything is leak free. Will see this week when I go the shop again and re-charge the system.

[My98RT10]

Update: I have everything together and went back to the shop that drained my refrigerant earlier. Apart from adding the factory fill of 822gr of R134a I calculated the amount of compressor oil that needed to be added.

It summed up to 83ml:


13ml were removed by draining the refrigerant
30ml due to replacing the drier (according to the shop manual)
40ml I drained from the compressor before disassembly


The DENSO oil installed from factory is ND-8 PAG, the equivalent aftermarket oil is a PAG 46 oil (you should make sure that you buy double end capped oil for better stability), of which I bought a small bottle (250ml).

Yesterday I went back to the shop and wanted to get my system filled again. I asked them what oil they have and it turned out that they only had PAG 100 oil, which is of higher viscosity than PAG 46. As I did not want to put in oil with different spec I left the shop again with an empty AC system.

Later I called another shop asking what kind of oil they would have available. Again, they had another type of oil, different spec... bummer.

I then decided to put in the needed oil myself, as I had the required amount available. So I poured the 83ml directly into the outgoing port of the drier. DENSO actually recommends NOT to add oil to the compressor directy, but to add it to the drier or condensator.

Today I went back to the shop and instructed them to pull a vacuum and only add refrigerant and not any oil, which they did. So, AC is working again (well, it worked before, I only tackled this because I detected some leaks). Will monitor the system now and hope for no more leaks.

BUT, what is really concerning me: obviously these 2 shops don't care what kind of oil is required by the specific make. They always use the one single oil they have available, regardless of what kind of compressor the customer has in its car. Most customers don't know and won't ask, but some oils should definitively not be mixed....

So, next time you go for a refill, ask the shop for the correct oil. Otherwise you run a risk of having different oils in your AC, which can cause problems with your compressor down the road.

[Boosted Motorsports]

Damn that looks like a pain in the ass! Props to you sir I would have just bought a new compressor (probably still would if needed) lol

[My98RT10]

Damn that looks like a pain in the ass! Props to you sir I would have just bought a new compressor (probably still would if needed) lol

Come on John, don't tell me you'd shy away from this? This would likely leave us without any video!? ;)

I think for someone who is replacing (almost) every component of the car (I intentionally avoided the term "upgrading") this is kinda piece of cake... :anonymous:

[My98RT10]

Yesterday I took it for a spin and measured the outgoing air at the center air duct with an oven thermometer. Ambient temp was 25°C (77°F). When idling the conditioned air temp was 9°C (48°F) and when driving, the temp went down to 4°C (39°F). Comparing it with the specs in the shop manual it seems to be in the ok range. I had never measured the temps in the past so I cannot compare it to what it was before I started the overhaul....there's probably not a big difference as I had still 766g of refrigerant in system when they drained it (total capacity is 822gr.).

Nevertheless, I'd be interested to hear, what kind of temperatures you guys achieve?

Here's the overhauled compressor before it went in again. Will share some more pics from the internals later....

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0282_zpsqfc7ekoz.jpg

[LifeIsGood]

Thanks for all the info. I really appreciate this thread. I'll be replacing mine in the very near future.

[Fatboy 18]

Nice Job

[My98RT10]

Thanks for all the info. I really appreciate this thread. I'll be replacing mine in the very near future.

You are welcome!


Nice Job

Thanks!

I still wanted to show the internals of the compressor, so here are some teasers :)

Front cover removed:

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0250_zpsiykkpqjy.jpg

Valve steel plates and gasket removed, obviously it is a 10 piston compressor (5 in the front and 5 in the back), hence the model name 10PA15C!?

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0252_zpshg4dwyuu.jpg

Center piece removed:

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0261_zps2zogrwg4.jpg

Compressor pistons:

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0263_zps1kqcwjwi.jpg

New o-ring installed:

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0265_zpsookb303z.jpg

A little bit of wipe down...

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0268_zpszdqdh2l4.jpg

New o-ring and valve steel gasket, lip seal protector installed to prepare for installation of the front cover w/new shaft seal...

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0272_zpsv8nngj15.jpg

Front cover back on with new shaft seal...

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0274_zpstwwisv8r.jpg

New o-ring also on connection plate...

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0277_zpslux6rjwj.jpg

Re-sealed product, ready to put the clutch and pulley back on...

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0278_zpsvxu0d4vd.jpg

[71firebird400]

Very cool! Thanks for the pics.

[My98RT10]

Here's again the overview of o-ring sizes I have used:

Compressor (2 different sizes):
9/16" x 3/32"
7/16" x 3/32"

Condenser (both connections same size):
2 x 7/16" x 3/32"

Drier (both connections same size):
2 x 9/32" x 5/64"

Tip: don't buy the Mopar drier (Viper/Mopar tax!!). Buy aftermarket part from Denso (DFD09001) or equivalent, should get it for around 15$ (or even less).

[LifeIsGood]

Don't forget to replace the schrader valves also as they may leak too.

I just ordered a new compressor. Anybody know the valve core sizes? I'm looking at them on Amazon. I haven't pulled mine yet.

28226

[My98RT10]

I need to check later today, what size I used. I bought an assortment of valves as I didn't know either and the correct ones were included. Now I have a bunch of sizes I don't need LOL

[My98RT10]

At least found a picture of the correct ones...

http://i1359.photobucket.com/albums/q800/My98ViperRT10/Air%20Conditioning/DSC_0307_zpsbnewpoqw.jpg

[03evoIII]

I just ordered a new compressor. Anybody know the valve core sizes? I'm looking at them on Amazon. I haven't pulled mine yet.

28226

where did you order your compressor from? Does it come complete with pulley/clutch, etc.? Cost? TIA!

[LifeIsGood]

RockAuto

DENSO (471-0355) A/C Compressor (http://www.rockauto.com/en/moreinfo.php?pk=993466&jsn=257)

Cost - $193.79
Discount 5% - $9.69
Shipping Ground - $6.99
Order Total - $191.09

I ordered it yesterday and got it today.

[03evoIII]

^^^Thanks!!!

[Dan Cragin]

We do quite a bit of AC work on the Gen 1-2 Vipers. Most common leakage problems are the o-rings at the compressor and condenser and the service port valves. Next would be the front compressor seal and hoses. 1999-2002 Vipers are known for a leaky high pressure hose at the compressor. Exhaust manifold heat damages the hose. The easy fix is to simply bend the factory exhaust manifold heat shield over the area where the heat is radiated.

Always install leak dye if it's a small leak, charge the system and drive it for a day. At that point the areas where the leaks are will be evident. The hoses can be sent out and repaired. Many are no longer available.

I always use the Factory red and black seals. The cheap green seals just get hard and leak after a year.

I have new compressors in stock for $200 each, so I always replace, not repair compressors.

Hope this helps.

[03evoIII]

Dan - could you supply all of the factory o-rings for all of the connection points as well? I'll be calling you. I need to get this fixed.:)

[Dan Cragin]

Yes, no problem, or I can get you the part numbers.

[98RedGTS]

part numbers would be awesome. I'll pick them up for a just in case moment.

[LifeIsGood]

Do you guys use anything on your o-rings during installation, like Nylog?

[Fatboy 18]

OK, I may need to tackle the AC compressor job, if I turn on the AC in my car the compressor clutch is squeeking, I sprayed some WD40 to the front of the clutch plate and the squeek has gone away but I don't think the WD40 will last long and am expecting the squeek to return (cars now done 105,000 miles).