I think you guys who read in the forum regularly would guess I wouldn't use these anyway because of the sucess I had with ARX, but what are the downside to solvent flushes OTHER than the fact they release a lot of sludge quickly into the filter. I'm just curious about this. Is there any effect on the internals having a solvent in there, or are they generally safe to use short term. One thing would also be once you introduce them you would probably be stuck with them a while at least in a small amount, because when you change your oil you are not going to get it all out. What do you think the effect is having a small amount but for the long term? I guess the upside would be a quick cleaning no matter what you got going on, but at what cost? Feel free to chime in solvent flush fans, other upsides I forgot when it comes to solvents?
Solvent flush question?
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There's a lot of wringing of hands over the possibility of a junk coming loose and blocking the uptake screen or small oil port. But has anyone heard of this actually happening? The evidence would be - I solvent flushed today, and within the wk the oil light came on, or within the next 6 mos I sludged.
Amsoil, etal, sure seem to hand this stuff out to any and all - if it could possibly choke an engine, it seems there would be litigation issues or something.
As far as it staying in your engine w/ your new oil - that depends on what's in the flush. If it's volatile solvents, then the trace amounts that are left will quickly evaporate. There shouldn't be much roaming around in there long term with Ams. flush (or it's harmless if it is) - since Amsoil tells you to go straight into your 25k/35k (whatever) OCI right after the flush. Though running a rinse for a few minutes with a cheap oil does give peace of mind. But then you've got traces of cheap oil.
And, if you've got a chunk of something that can dislodge because it got hit with 20 minutes of solvent flush (which I'm beginning to understand - most of these once mixed with multi-qts of your own oil aren't not actually that harsh), then I think you've got a good chance of said clot coming loose and clogging your heart while just running your regular oil.
Amsoil, etal, sure seem to hand this stuff out to any and all - if it could possibly choke an engine, it seems there would be litigation issues or something.
As far as it staying in your engine w/ your new oil - that depends on what's in the flush. If it's volatile solvents, then the trace amounts that are left will quickly evaporate. There shouldn't be much roaming around in there long term with Ams. flush (or it's harmless if it is) - since Amsoil tells you to go straight into your 25k/35k (whatever) OCI right after the flush. Though running a rinse for a few minutes with a cheap oil does give peace of mind. But then you've got traces of cheap oil.
And, if you've got a chunk of something that can dislodge because it got hit with 20 minutes of solvent flush (which I'm beginning to understand - most of these once mixed with multi-qts of your own oil aren't not actually that harsh), then I think you've got a good chance of said clot coming loose and clogging your heart while just running your regular oil.
I'll add this question to yours (I don't think it's too much of a thread jack) -
When I first learned of the Sienna sludge issue (early 2002), I nervously called a local (well known) engine rebuilder - asked him about running a flush. He said to get a five minute flush and run it 20 minutes. Then I talked to a Yota service mgr (different dealership from the one I use) - he said they have the flushing machine they could use, but otherwise to take a 5 minute flush and run it 15-20min (btw, when he looked at my dipstick, he didn't think I needed the flushing machine). I ended up taking the advice of a mech at my regular dealership - got the BG Purge - he said run it ONE HOUR - I ran it 40 min. So, all these mechs are basically laughing off the five minute interval. So, once I do my Amsoil flush (recommended 15-20 minute) - should it ideally (and safely) be pushed to 30 minutes or more.
When I first learned of the Sienna sludge issue (early 2002), I nervously called a local (well known) engine rebuilder - asked him about running a flush. He said to get a five minute flush and run it 20 minutes. Then I talked to a Yota service mgr (different dealership from the one I use) - he said they have the flushing machine they could use, but otherwise to take a 5 minute flush and run it 15-20min (btw, when he looked at my dipstick, he didn't think I needed the flushing machine). I ended up taking the advice of a mech at my regular dealership - got the BG Purge - he said run it ONE HOUR - I ran it 40 min. So, all these mechs are basically laughing off the five minute interval. So, once I do my Amsoil flush (recommended 15-20 minute) - should it ideally (and safely) be pushed to 30 minutes or more.
To prevent a thread jack (on my part) we have two questions here -
1.) Residual solvent flush messing with new oil. (?)
2.) Push Amsoil flush to 30 minutes or more. (?)
1.) Residual solvent flush messing with new oil. (?)
2.) Push Amsoil flush to 30 minutes or more. (?)
Apparently we may have to answer own questions. Perhaps you could purposely leave 1/2 pint of solvent in your engine and do a UOA at the end of your next OCI. Meanwhile I'll run Amsoil flush for 1 hr 30 min and see if the temp guage rises.
Then we can be the new Science Rockets on BITOG !
Then we can be the new Science Rockets on BITOG !
I have done flushes on many cars throughout the years.
I always use flush using 20w-50/new filter....and 20% solvent.
usually kerosene.
Run the engine 20-40mins, drain black gunk out.
Install new oil and filter, and drive as normal.....easy
I have also done 2-3 consecutive flushes on the same engine...., it was very badly sludged., each time the oil/solvent came out a little cleaner.
I have honestly not experienced any negative effects on gaskets, or internals, all the cars I have flushed were sold with very clean engines, and ran perfectly fine.
I think this fluch issue, like the FRAM issue is WAY OVERBLOWN !!!!!
1 Dopey mechanic puts in 100% capacity kerosene, engine blows, and all of a sudden its bad for ALL engines.
20% capacity of solvent, 30mins and you are fine....and with the 50weight oil, it gives a nice buffer of lubrication.
I always use flush using 20w-50/new filter....and 20% solvent.
usually kerosene.
Run the engine 20-40mins, drain black gunk out.
Install new oil and filter, and drive as normal.....easy
I have also done 2-3 consecutive flushes on the same engine...., it was very badly sludged., each time the oil/solvent came out a little cleaner.
I have honestly not experienced any negative effects on gaskets, or internals, all the cars I have flushed were sold with very clean engines, and ran perfectly fine.
I think this fluch issue, like the FRAM issue is WAY OVERBLOWN !!!!!
1 Dopey mechanic puts in 100% capacity kerosene, engine blows, and all of a sudden its bad for ALL engines.
20% capacity of solvent, 30mins and you are fine....and with the 50weight oil, it gives a nice buffer of lubrication.
Well Eric I have a brand new car so I wont be guinee piging it for a while. I'm on the Autorx maintenance dose plan so I hope I never need to worry about it. My wifes car may need a flush as an additive really screwed it up, but so far the Arx seams like it's working. If it comes back I will have to consider something stronger. Maybe another consideration is when is a solvent flush necessary?
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Nicholas,
Simple and to the point. Thank you!
Kerosene gets poo-pood a lot around here - but I'm wondering what's in the more expensive stuff that can give it that much advantage over kerosene in such a short time frame. I can see where hi-fluetent chemistry can distinguish the slow cleaners (Neutra vs. A-rx, etc). But in a quick 20 minute splash, when Kerosene is a proven dissolver of all things petro. (?)
There was however that one poster claiming a friend used Gunk to little effect, then Amsoil flush to great effect. So I'm still glad I got the Amsoil. But I'm definitely suspicious about this - Seriously trumping Kerosene in 20 minutes - that just doesn't sound right. (Perhaps in the Gunk then Ams. scenario - the Gunk started the process, but then the dose of Amsoil flush put the cleaning in full swing. (?))
If someone has home test case evidence of quick acting solvents outperforming kerosene, plse enlighten us! (I still covet the costly BG Purge - it's Pine Sol on steroids).
Simple and to the point. Thank you!
Kerosene gets poo-pood a lot around here - but I'm wondering what's in the more expensive stuff that can give it that much advantage over kerosene in such a short time frame. I can see where hi-fluetent chemistry can distinguish the slow cleaners (Neutra vs. A-rx, etc). But in a quick 20 minute splash, when Kerosene is a proven dissolver of all things petro. (?)
There was however that one poster claiming a friend used Gunk to little effect, then Amsoil flush to great effect. So I'm still glad I got the Amsoil. But I'm definitely suspicious about this - Seriously trumping Kerosene in 20 minutes - that just doesn't sound right. (Perhaps in the Gunk then Ams. scenario - the Gunk started the process, but then the dose of Amsoil flush put the cleaning in full swing. (?))
If someone has home test case evidence of quick acting solvents outperforming kerosene, plse enlighten us! (I still covet the costly BG Purge - it's Pine Sol on steroids).
You've hit it. If you flush your engine with a solvent based product you should be aware of what you're doing. If not, there is a risk. There may also be a risk from some unknown condition. You have to be prepared for the fallout. The advantage of Auto-Rx over solvents is that Auto-Rx is gentle safe and slow and still very effective. I think a lot of members here, have used a solvent and followed it up with Auto-Rx. This is the kind of thing a more informed owner will do and the results are good. I wonder how many problems down the road can be tracked back to a solvent flushing, but the connection is never made. My brother had one of those hot engine flushes and had a string of problems after that, fouled plugs, multiple problems with the pcv system and a flashing oil light. The dealer told him it had nothing to do with the flush and that he needed his engine overhauled. I ran him through three cycles of Auto-Rx over 6k miles with a lot of extra oil changes in the rinse cycles on his V6 Tundra with 144k miles on the clock. It runs great now and I've told him that if he does not start changing his oil I'm going to kick his dog. The dealer told him he is running on "borrowed time" and his engine is going to fail any time now. I don't let him go to that dealer any more. He is on dealer restriction. We found him a mechanic to work on his car, no more credit card debit technicians are allowed to touch his truck.
"He is on dealer restriction."
Excellent. Superb. Fantabulous.
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Excellent. Superb. Fantabulous.
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http://auto-rx.activeboard.com/index.spark?forumID=108943&p=3&topicID=12762845
Interesting article I saw on the arx forum, a third party link had the same concern about the left over solvents. A really good test would be to see how much solvent it takes to break down x amount of oil, or change the chemistry of that oil.
Interesting article I saw on the arx forum, a third party link had the same concern about the left over solvents. A really good test would be to see how much solvent it takes to break down x amount of oil, or change the chemistry of that oil.
I've taken several high mileage engines, with reasonable but not obsessive OCI history, drove it to pboys or Azone(10 miles), added a quart of gunk flush to the 'hot' engine (which overfilled engine by a quart), then DROVE 15+ minutes home, and then changed the oil.
I've done this several times trying to create the 'worst case' scenario for kero, distillate, or light oil flushes. Each engine always ran better(power and MPG), sounded quieter, and have clocked 50k-100k more miles without any engine issues.
I do recommend a short OCI after a flush and even a move up in viscosity prior to planning the flush. I do recommend that a flush should only be run 5-10 minutes on a COLD engine without any engine loads. I also do recommend that if you have an unknown or poor maintenance history, that you inspect your engine by pulling off the valve cover and/or oil pan. Manual cleaning as much as possible and knowing what you're getting into is a must.
You should also research your engine. Known sludge monsters should avoid quick flushes. Simply shorten the OCI interval, use a quality oil(like a synth), and keep on driving.
I also understand the benefit of extending the time of a flush. But, oil viscosity thins as it heats up. Unless you've moved up a grade or two in oil wt, you shouldn't extend the flush time. This is where I'll disagree with those tech/mechs/dealers dragging a flush on too long. Yep, heated solvent works better. But, at what risk? I guess that the gamble is that an engine at idle, without any load, won't need to worry about the loss in oil viscosity. Why risk it?
If you just purchased a used vehicle, if VC/pan inspection isn't feasible, then several 2k OCIs prior to any flushes should be performed. And, those slow flushes, like ARX, pint shots of MMO or Rislone, Lubegard... would be better choices then blindly throwing a quart of kero into the unmaintained uninspected engine.
I've done this several times trying to create the 'worst case' scenario for kero, distillate, or light oil flushes. Each engine always ran better(power and MPG), sounded quieter, and have clocked 50k-100k more miles without any engine issues.
I do recommend a short OCI after a flush and even a move up in viscosity prior to planning the flush. I do recommend that a flush should only be run 5-10 minutes on a COLD engine without any engine loads. I also do recommend that if you have an unknown or poor maintenance history, that you inspect your engine by pulling off the valve cover and/or oil pan. Manual cleaning as much as possible and knowing what you're getting into is a must.
You should also research your engine. Known sludge monsters should avoid quick flushes. Simply shorten the OCI interval, use a quality oil(like a synth), and keep on driving.
I also understand the benefit of extending the time of a flush. But, oil viscosity thins as it heats up. Unless you've moved up a grade or two in oil wt, you shouldn't extend the flush time. This is where I'll disagree with those tech/mechs/dealers dragging a flush on too long. Yep, heated solvent works better. But, at what risk? I guess that the gamble is that an engine at idle, without any load, won't need to worry about the loss in oil viscosity. Why risk it?
If you just purchased a used vehicle, if VC/pan inspection isn't feasible, then several 2k OCIs prior to any flushes should be performed. And, those slow flushes, like ARX, pint shots of MMO or Rislone, Lubegard... would be better choices then blindly throwing a quart of kero into the unmaintained uninspected engine.
Out of all the forums I have read, and all the research I have done, there has never been proof that the use of kerosene, mineral spirits, biodiesel, GUNK, etc. have caused issues with breaking off large chunks of sludge "too quickly."
I agree with unDummy, that it wouldn't be a good idea to blindly use kerosene in a poorly maintained vehicle. I'd at least give it a couple of OCIs with 50/50 conventional and synthetic oil first. If things didn't improve, I'd do a 50/50 ratio of 20w-50 and kerosene and idle it for 10-15 minutes, shut the engine off, and repeat 2 more times every 3 hours (top off with a 50/50 ratio if needed). Then do a 15 minute flush at the end of each OCI for the following 3-5 OCIs, or until things improve.
One thing to remember, low volatile solvents won't remain in the crankcase for long. So in the event that you have .4 quarts kerosene (the amount leftover from an oil change) to 5 quarts oil, that .4 quarts should vaporize during normal driving. Just top up as necessary.
Auto-RX is $25 and has worked for some, kerosene is less than $3 (last I checked it was, but I could be mistaken) a gallon and has worked for many as well. Which one protects more? H*** if I know. Which one works better? That's user/application dependent in my opinion.
Give them both a try, that's what I would recommend.
I agree with unDummy, that it wouldn't be a good idea to blindly use kerosene in a poorly maintained vehicle. I'd at least give it a couple of OCIs with 50/50 conventional and synthetic oil first. If things didn't improve, I'd do a 50/50 ratio of 20w-50 and kerosene and idle it for 10-15 minutes, shut the engine off, and repeat 2 more times every 3 hours (top off with a 50/50 ratio if needed). Then do a 15 minute flush at the end of each OCI for the following 3-5 OCIs, or until things improve.
One thing to remember, low volatile solvents won't remain in the crankcase for long. So in the event that you have .4 quarts kerosene (the amount leftover from an oil change) to 5 quarts oil, that .4 quarts should vaporize during normal driving. Just top up as necessary.
Auto-RX is $25 and has worked for some, kerosene is less than $3 (last I checked it was, but I could be mistaken) a gallon and has worked for many as well. Which one protects more? H*** if I know. Which one works better? That's user/application dependent in my opinion.
Give them both a try, that's what I would recommend.
I've always wondered about the idea of a piece of sludge coming off and getting stuck in the filter or oil passage way due to the use of harsh solvents.
I figure that if the solvent was strong enough to cause the bond between the large piece of sludge and the engine wall (original location of the sludge) to dissolve and break loose thereby getting caught in the filter or passage way, why won't the solvent dissolve that large piece of sludge that is stuck and having all of that oil run by it?
Think about it... what makes that area of sludge that breaks weaker than the rest of the sludge? And if the solvent dissolves that sludge won't it dissolve the other stuff as well over time?
I figure that if the solvent was strong enough to cause the bond between the large piece of sludge and the engine wall (original location of the sludge) to dissolve and break loose thereby getting caught in the filter or passage way, why won't the solvent dissolve that large piece of sludge that is stuck and having all of that oil run by it?
Think about it... what makes that area of sludge that breaks weaker than the rest of the sludge? And if the solvent dissolves that sludge won't it dissolve the other stuff as well over time?
Just wanted to post this on a thread that was close to what i wanted to say.
I tried AUTOrx, and got angry when my oil didn't get dirty.
Today, i used the Amsoil engine flush for 20 minutes and my oil still came out yellow..So i guess my motor was in excellent condition (which it should, i'm anal about it) so My observations of Autorx were unfair..if a solvent couldn't get my oil dirty by dispersing 'sludge' and 'deposits' quicker, then i of course shouldn't of expected AutoRX to do it either.
If you've got a new car, i would say go with the Amsoil engine flush..no need to be eager to put miles on the motor when you don't have to worry about clogging anything.
I tried AUTOrx, and got angry when my oil didn't get dirty.
Today, i used the Amsoil engine flush for 20 minutes and my oil still came out yellow..So i guess my motor was in excellent condition (which it should, i'm anal about it) so My observations of Autorx were unfair..if a solvent couldn't get my oil dirty by dispersing 'sludge' and 'deposits' quicker, then i of course shouldn't of expected AutoRX to do it either.
If you've got a new car, i would say go with the Amsoil engine flush..no need to be eager to put miles on the motor when you don't have to worry about clogging anything.
Thanks for the follow up Kiefers. At least now you know your engine is free of any sludge problems. My other concern is do solvents change the chemistry of oil, and if so how much does it take to lessen the lubrication abilities of your oil. I don't think a virgin analysis will tell the story, but maybe a UAO taken on a non oil flush change and a second taken with say 3 ounces of solvent per quart of used oil dumped in. Amsoil flush is 16 ounces, or 3.2 ounces per quart of oil considering a car that takes 5 qts. Or a test that takes that into consideration but is more scientific. How much do you think these products are tested?
Amsoil has some concern about this too I think because they warn against using it in many other areas, from Amsoil site, "*Note: Engine Flush is not recommended for use in transmissions, differentials, air-cooled engines, engines that share a common oil sump with the transmission..."
It sounds like metal to metal contact worries them in using their solvents in these other areas. Amsoil is mainly solvent: Why would they not use the product in these other oil lubricated parts that need cleaning, unless it was because they are afraid of the lessened lubrication properties of the host oil? Maybe the "after change" left over solvent in these areas can be a problem, but with a T-Tec I would think this is less of an issue because it purges almost all the oil out.
I'm not totaly against solvents, but I think there are some un-answered questions regarding the risks of them. I'm just skeptical that real comprehensive testing isn't done on them. And I'm not saying is Autorx is any different in this area, other than it has passed the test of so many BITOGers. But then again it looks like Amsoil has passed the test by some people here too. It's just that 3 ounces of solvent per quart seams like a lot of potential for it to break down the oil itself, or if nothing else thin the ---- out of it.
Beyond the thinning of the oil using solvent flushes, the quick evaporation would be a downside as well. The solvent breaks down sludge, then disappears on the job. Lord knows that the host oil won't suspend all the ---- the solvent dislodged. So for sure solvent flushes should only be idled for a couple, may be few minutes and dumped immediately. With the normal solvent flush the oil is definitely thinned out. So what happens to the cam and crank seals. Beyond swelling potential, it is highly likely that semi dissolved gunk is going to impact them, if not immediately, then possibly soon after.
Solvent flushes do not help the oil carry or suspend more junk, probably less. I prefer not to mess with solvent flushes.
Solvent flushes do not help the oil carry or suspend more junk, probably less. I prefer not to mess with solvent flushes.
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