ARX or LC (or neither) for this situation?

[kang]

I have an air-cooled Porsche flat 6. It had some issues with carbon build-up in the cylinders, which I have largely taken care of with both in-the-tank fuel system cleaners and sucked-into-a-vacuum port cleaners. I have some lingering concern that there might be some carbon still stuck on the rings. Compression is good, and the engine is running the best it has in a long time, so if there is some carbon on the rings, it’s not much.

The car has had high quality synthetic oil it’s entire life, mostly M1, currently M1 0W-40. OCI’s have been short, like
ARX is a single shot cleaner, but I don’t like the idea of running non-synthetic oil in this engine. I do the occasional autocross, and the engine sees high revs regularly. I also don’t like the idea of the 2,500 OCI’s. Changing the oil on this car is a pain (see http://p-car.com/diy/changeoil/). It’s also expensive. The two filters run about $30 (no $3 filters from Pep-Boys), and the sump contains 12 quarts of oil, about 10 of which get changed, so that adds up. One thing I thought of was to add one bottle of ARX about halfway through my 5,000 OCI. Given that I doubt there is any sludge, I don’t think changing the filters at that point would be necessary. I’d just complete that 5,000 OCI and then change the oil and filters at the normal time. This would be about 1/2 the recommended dosage of ARX, in synthetic oil. On the other hand, ARX seems mostly for soft, sludge like deposits, rather than hard carbon deposits on the rings.

LC says it melts hard deposits (the LC website claims “will literally melt (soften and emulsify) carbonaceous deposits”), but it is also a more continuous application, running with a maintenance dose basically forever. I don’t like that idea at all.

In general, I don’t like oil additives, so perhaps my best solution is to just let the detergents in M1 clean up what small build-up there might be on the rings.

Thoughts? Suggestions? Thanks in advance.

 

[Quest]

Originally Posted By: kang
On the other hand, ARX seems mostly for soft, sludge like deposits, rather than hard carbon deposits on the rings.

LC says it melts hard deposits (the LC website claims “will literally melt (soften and emulsify) carbonaceous deposits”), but it is also a more continuous application, running with a maintenance dose basically forever. I don’t like that idea at all.

In general, I don’t like oil additives, so perhaps my best solution is to just let the detergents in M1 clean up what small build-up there might be on the rings.





Depends on what you mean by hard carbon deposits on rings: if you are referring to the bottom-end (aka the 2nd compresson ring, oil control ring, etc.), AutoRx can basically dissolves anything there so long as you give it sufficient amount of time, quantities as well as operating conditions for it to works it's way into that part of the piston.

If you are referring to the top ring or anything close to the combustion chamber, I'm afraid AutoRx cannot work it's way into there for you may need some sort of combustion chamber cleaner (where oil +autoRx cannot reach, you aren't gonna get the benefits of AutoRx cleaning in those regions).

No comments on LC.

As for Autocrossing, etc. and mineral oil vs synthetic, you need to get this straight: most OTC conventional oil are "blended" oil meaning that it may contains GpII with GpIII or similar in order to meet certain API/ILSAC specifications. So long as you observe/practice conservation OCI and be careful about the viscosity used in your engine, I cannot see how/why conventional oil cannot be run once or twice during AutoRx rinse phase and then switch back to your "so-called" synthetic. Mind you tho: M1 syn is not "true" syn (RL and Amsoil both are true "syn") but more like a syn blend. To find out more about the stories behind recent M1, plse perform a search.

Q.

 

[Frank]

Please read the website (www.auto-rx.com) we work with synthetic oils (as long as there is no sludge issues) cleaning your ring packs with Auto-Rx is safe and it works while you drive.

Auto-Rx is not a 'single shot" or is it an additive. take a look at
the Mobil 1 user and his oil analysis found on home page of web site.

 

[Craig in Canada]

While it can't be said about all grades of M1, most seem to believe that M1 0W40 is largely PAO.

To the OP: I had a Porsche myself a couple of years ago. I wouldn't fear running an excellent 15W40 or 15/20W50 dino oil in order to reap the benefits of ARX. Technically current ARX directions allow the cleaning phase to be run with synthetic oil but the rinse must still be group III or less.

If you run ARX, your autocross and track excursions will probably help the cleaning action immensely - it loves heat. With your dry sump system you'd probably need two full bottles - maybe 2.5-3 (without doing the math). Depending on your oil consumption at these events you may need to make special consideration also.

I don't like to run non-synthetics either, but many dino oils are quite good these days especially for an OCI that is only the ARX distance. As long as it isn't a Canadian winter, I've overcome my fear of dino particularly for short OCIs using ARX.

Personally, I'd suggest ARX over LC. LC is great for varnish deposits and certain types of HLA problems. ARX is the king for ring deposits at this point. I'd also consider running a maintenance dose of ARX all the time to keep ring carbon in check. You could even try starting with a maint dose in your M1 0W40 (or maybe a double maint dose) and see if you notice any improvement. It won't be as effective as a proper clean cycle but it also doesn't require any special OCI habits.

If it were my car, I'd probably pick a 15W40 HDEO and do the full treatment. Use the drained oil to run your lawnmower for a couple of years , or your other car, or whatever. I'd then return to the synthetic of my choice (which knowing what I know now probably wouldn't be M1 0W40, but it is factory approved) with ARX maintenance dose.

I'd also consider getting the fuel injectors rebuilt off of the vehicle. In high output/high compression engines this can really affect smoothness, power delivery and fuel efficiency (not the #1 concern in a P-car

 

[BarkerMan]

Kang, in my experience with high performance engines Auto-Rx has been effective in cleaning out the rings without damaging the oil's ability to lubricate. I have been experimenting with 4 ounce maintenance does and I got the idea of moving up from 3 ounces because of positive results first in high performance engines and then daily drivers. Myself and others building high performance engines are using a 4 ounce dose in a brand new engine. The results have been impressive. Wear numbers spike and then drop. I think it's because Auto-Rx is getting stuff out of the engine, even a new one. After the spike the numbers drop dramatically. As for your concern about non-synthetic oil, don't worry about your Porsche. If nothing else your engine type lubricates well with plenty of reserve. I have used Auto-Rx with Red Line and RLI with good results in air-cooled Porsche engines. I have noticed no difference in cleaning when using synthetic oil in the clean phase and as for the rinse phase I have noticed that it takes much longer to get the gunk out and dyno is the only way to go with a really gunked up engine. Some of the 'parking lot racers' in the LA area use diesel grade oil in their Porsche engines and change it every weekend they race, that is change the oil not the filters so your idea of keeping the filter is in line with others. One of these cars is a Ruf Cayman that uses Mobil 1 Turbo Diesel a 0w-40 (I think) with Auto-Rx. (As a side note several friends involved in racing have driven this car and declare it as least as much fun to drive as a GT-3 and more comfortable on the street). It appears that Auto-Rx has taught an old dog like me some new lessons. One is that it works without getting in the way of your current engine oil and two that I missed the value of the maintenance dose including the neeed to start the dose on a brand new car just driven out of the showroom. And as a side note it appears that Auto-Rx has some anti-friction properties. Besides raising compression in an engine my personal car is getting better mileage, not much but it's there, a couple of percent. It may be a combination of anti-friction and improved ring seal with better combustion efficiency. I've also noted improved calculated BMEP numbers in steady state running on the dyno during fuel system mapping on engines after run-in. I think that what this Auto-Rx does might just be a little more complicated under the hood than just chasing deposits. This might be why no one has reverse engineered Auto-Rx.

 

[dargo]

I have used both; both adds, help out etc. I like one more then the other based on miles per oil change and $$

 

[Rick20]

ARX works very quickly on piston ring deposits. This is due to the high heat and pressure levels surrounding ring packs during in situ cleaning. ARX will clean ring packs regardless of oil used as the host.

You have already treated the top end of the cylinders with your gas adds, now go and clean up the ring packs from the bottom up. You won't be dissappointed. I would suspect that the ARX will clean up the ring packs within 500 miles of operation.

 

[kang]

Thanks for all the responses.

First of all, it looks like ARX wins over LC, no contest. Yes, I’ve done the top of the rings with the combustion chamber cleaners, now it’s time for the bottom rings.

Second, it seems like there are no issues running with synthetic oil for both the clean and rinse phases. Even Frank from Auto-Rx confirms this. I have no sludge or gunk issue, so no worries there. Yes, I agree no harm would be done with a short OCI with dino, but I don’t really see the need.

Third, it seems my original idea of adding ARX halfway through my 5,000 mile OCI is a good one. I usually burn off about a quart every 2,500 to 3,000 miles, so I would just replace that with 2 bottles of ARX. 2 bottles in my sump gives the recommended dosage (which I think is 2 ounces of ARX per quart of oil).

Then I’m done! The next oil change will be the rinse cycle (although I don’t see why the carbon won’t rinse away, at least partially, during the cleaning phase). I’ll decide on a maintenance dose or even a second application depending on the results of the first application. Like I said, my engine has good compression and no sludge, so I’m not expecting I’ll see much.

 

[NYSteve]

Group IV & V Synthetic can be used for the clean phase only. For rinse it is recommended that only up to Group III be used. PP or Amsoil XL line would be the Grp III recommendations from me. There are others out there. Doing a search will provide more detailed answers.