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imserve

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Greetings,

I have been reading the presoak discussions, trying to get the best cleaning possible on my IBA....after having reps from 2 soap companies out still have a few questions on LO HI presoaks.

Both suggested LO HI.....
one said, strong LO followed by med(strength) HI
Other said, med LO followed by strong HI

I know LO generally cleans glass chrome better and HI generally cleans paint better....my biggest question is:
Does LO enhance cleaning of HI? In other words, for the paint, is LO first a positive for better paint cleaning?
Or, can LO first actually be a negative for general cleaning?

Appreciate any responses and especially those that understand the science of cleaning
 

mac

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Well you have swerved into one of those great unknown areas about cleaning. Lo, Hi, strong, weak. They really don't mean much. Low pH is an acid, and high is an alkaline. What works best in one part of the country may not work well where you are. It's all chemistry. The pH of the dirt can affect things, as does the hardness of the water, which almost no one ever checks. It takes a little experimentation to find what works best for you. Most good soap reps will let you try their products for a short while to prove that it works, and that they know how to mix and apply it. Ask them to do that. Try to stay with a recognized brand, and stay away from home blenders, or people blending under the so called guidance of a major name. For instance there is a Blendco guy down here that mixes his products, and there is no consistency. To complicate matters, just doing a titration test to determine strength will not always tell the whole story. The surfactants in the detergent can greatly affect how it performs. Titrating is a good indicator though. And things can change. There are parts of the country that will have pollen blooms that may need different treatment than regular old dirt. I'm assuming you are using a touchless machine as opposed to friction. Let us know how things work out.
 

imserve

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Thanks,
I understand the variables and am getting a pretty decent wash on my touchless using softened water...just of a type that likes to understand the process and getting max possible out of my machine. I have experimented and will be doing more.

I am familiar with using high alkaline soaps in a commercial laundry, pretty much the higher PH you go, the better cleaning you get.

Hoping someone can explain how Acid and Alkaline work together in a 2 step presoak...do they compliment each other? Or can they negate each other?

For example, if time and water weren't an issue, would it be better using LO or HI separately? (HI with a long dwell time followed by a hi-pressure rinse, then LO followed by rinse, or vice versa)

I can't wrap my head around the 2 step process....seems like as soon as the 2nd step is applied it would cancel out the other as it would bring the combined soaks to a neutral......
 

carwashireland

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I always start my low ph at about half the strength of the high then increase the low until the eyebrows of the wind shield get clear. I typically have a 20 sec dwell after applying low then apply my high. I have a 20 to 25 sec dwell on my high before washing. If cars are not clean I increase my high ph strength until they are clean. If your soaps do not work when doing this and you know your pressure is good and water is soft then try new soap!
If you apply low then wash then high you will be diluting the high so best to go low, high then wash imo.
 

imserve

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Thanks for the replies....

I am looking for a little different discussion than what I have seen in previous threads....

Is there a science behind lowering the PH on the car followed by HI directly on top of the LO.....Like maybe a (break or something when transitioning suddenly from LO to HI) ie, do they compliment each other ?

I know some use a booster for HI....so I'm wondering if the goal is a Hi PH.....wouldn't the LO kinda neutralize that?

So, does Lo PH make HI PH work better? or is the LO HI 2 step process simply a way of covering all different types of dirt in a wash?
 

carwashireland

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Thanks for the replies....

I am looking for a little different discussion than what I have seen in previous threads....

Is there a science behind lowering the PH on the car followed by HI directly on top of the LO.....Like maybe a (break or something when transitioning suddenly from LO to HI) ie, do they compliment each other ?

I know some use a booster for HI....so I'm wondering if the goal is a Hi PH.....wouldn't the LO kinda neutralize that?

So, does Lo PH make HI PH work better? or is the LO HI 2 step process simply a way of covering all different types of dirt in a wash?
The main reason for the low pH is glass cleaning and chrome. When you put the alkaline over the top of it their is an exothermic reaction that helps to heat the soaps a little and then the alkaline will overwhelm the acid. At least it does if the strengths are set up correctly. I guess it probably covers more dirt types also, but my reason for 2 x step is windshield eyebrows. I used to have all single step machines which cleaned well, but the 2 step is a more complete clean. Keep the foam low also on the acid as you want it to run off the cars as much as possible begote applying alkaline
 

imserve

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When you put the alkaline over the top of it their is an exothermic reaction that helps to heat the soaps a little and then the alkaline will overwhelm the acid.
So does this reaction help the Alkaline clean better?

So in the summer I used a bug product for HI PH. the rep said to do that first followed by the LO...normally we did LO first.
This stuff was thick, foamy and got complaints that glass wasn't clean, also felt it didn't clean bugs much better at all
 

JGinther

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To make it really complicated:

The two are opposites - they neutralize eachother. They have different purposes. Alkaline detergents are there to break down oily dirt. Acidic Presoaks are meant to remove/prevent oxidation - which makes shinier finishes, and reduce mineral deposits. Oh yeah... and to sell more soap. You have to have the second one stronger than the first when putting them on top of each other - otherwise, you have made water. (Hydronium ion plus hydroxide ion = H20). But as others mentioned, surfactants, solvents, chelants, and other ingredients all have their part of the equation also - its not even close to just a pH game. But, for those ingredients to work, they need to be in their proper environment: an anionic surfactant needs to be in an alkaline solution for the surfactant to work.
 

PEI

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There are two ways to produce a clean car with a two step cleaning process.

You can use an aggressive low pH that will simply eat through the road film and follow with a weak high pH to nuetralize and stop the low pH. This tends to produce a very consistent level of cleaning and a dryer car, but can reduce the shine. A word of warning when using this kind of cleaning, aggressive acid doesn't just eat oily road film, it dissolves everything (road film, clear coat, concrete, glass, and your equipment).

The other way is to use a non-aggressive low pH that will thin the oily road film and allow the aggressive high pH to break the film, lift it from the surface of the car and allow the high pressure rinse to deposit it in the car washes pit. This works because the high pH bonds with the oil in a process known as saponification. The trick with this process is to thin the oily road film enough that the high pH can lift it from the surface, because it will still bond to the film even if it can't lift it. When it works you will get clean cars with very little damage. When it doesn't work you can make cars look dirtier than when they came in. While this doesn't do a lot of damage compared to the other way of cleaning it will swell o-rings and cause injectors and check valves to fail. This form of cleaning produces shinier cars but makes drying more difficult.

The other part of the cleaning that both a good low and high pH soap should have is a blend of surfactants. These are solvents that can also break through the oily road film so that the high pH can lift it from the surface of the car. The best example of how surfactants help with cleaning comes from the laundry industries use of them to remove ring around the collar.

I hope this helps.
 

imserve

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You have to have the second one stronger than the first when putting them on top of each other - otherwise, you have made water
Thanks,

That would explain why I got complaints about poor windshield cleaning when doing the Hi PH bug product(recommended by my rep to do Hi first)...I just switched the LO to presoak 2 without changing the strength

So generally I would get more out of HI if I do it first? And do LO first if my glass cleaning is not good?
 

APW

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I always start my low ph at about half the strength of the high then increase the low until the eyebrows of the wind shield get clear. I typically have a 20 sec dwell after applying low then apply my high. I have a 20 to 25 sec dwell on my high before washing. If cars are not clean I increase my high ph strength until they are clean. If your soaps do not work when doing this and you know your pressure is good and water is soft then try new soap!
If you apply low then wash then high you will be diluting the high so best to go low, high then wash imo.
I only have a 10 second dwell time after both low and high have been applied. Im wondering if I upped the dwell time or put a dwell after each pass, if I would clean better. I've been told if you have too long of a dwell time that the dirt will bond back to the car.
 

Greg Pack

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I always heard about pre soaks producing an exothermic reaction. Ok, I made a C in Chem 102 ( I would have paid more attention if I knew I was going to end up in the car wash business) so take this for what it is worth. But I assume that a meaningful exothermic reaction can be measured with a thermometer. Take and mix equal amounts of your low and hi presoak solutions together and see if the temp changes. In my case they didn't.

Pretending that I know nothing about low, high,alkaline, acid, etc and what is supposed to happen here have been my observations:


Every time I increase the strength of my low ph and use it as a first pass, my paint cleaning effectiveness gets worse, but my glass eyebrow usually improves.

I can boost the alkalinity of a just about any product and it has a dramatic effect on the paint cleaning ability.

The stronger the high, the better the paint cleaning up until a certain level, then the cleaning ability levels off.

Aside from HF users, I know of no one that uses just low ph at their site. There are plenty of people that use only high ph products though.

So I tend to use a weak low as a first pass, followed by a very strong boosted high. For lack of a better term the boosted high punches through the low and does its' job instead of being neutralized. In the winter I may swap to high-low or high-high even but I'm not in the snowbelt so ice melt compounds are not a concern here. Its still not perfect, and complicates the cleaning process. Less dilligent owners in the area are probably best sticking with high-high.

IMO cloth is the way to go if you have the market for it in your area. However, every frigging C store has a cloth rollover, so my touchfrees have developed a niche of sorts.
 

imserve

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Every time I increase the strength of my low ph and use it as a first pass, my paint cleaning effectiveness gets worse, but my glass eyebrow usually improves.
Thanks, very helpful

Lets say in summer with bugs etc, would you say doing HI HI with no Lo would do a better job? (on paint) of course the glass would suffer

In the winter I may swap to high-low or high-high
Can you expand on why you would do this? What would be the difference in cleaning effect?
 

washnshine

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IMO cloth is the way to go if you have the market for it in your area. However, every frigging C store has a cloth rollover, so my touchfrees have developed a niche of sorts.
I’m sure you maintain your equipment and site better, as well as offer a higher quality wash and better promotions than any of your C store competitors.

My first job was at a Hanna tunnel in the 1980’s. There were three Hanna tunnels in the town. All were basically the same equipment package. One was in a gas station and not well maintained. The other two were much more professional operations with well trained attendants and the buildings and grounds were kept nice and clean. Those two washes did probably 90% of the washing in that town. The gas station made its money on gas and convenience items and the wash was an afterthought, as is often the case.

Equipment alone does not make a succesful wash - operators do. Get what you want to clean with and run your business better than the C stores. It won’t be difficult!
 

Greg Pack

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Thanks, very helpful

Lets say in summer with bugs etc, would you say doing HI HI with no Lo would do a better job? (on paint) of course the glass would suffer


Can you expand on why you would do this? What would be the difference in cleaning effect?
Most bug removers are high ph or neutral with lots of solvent (butyl), so I'm assuming that high ph presoak is going to work better on bugs. So yes, a high/high or high/ low would likely work better at bug removal if that is your main concern. Dwell helps a lot. I actually program my machine to do a high pressure bug pass towards the end of the wash after maximum soak time and the bug carcasses have been wet with both various chemicals and water.

I have no experience with snow but I understand that low ph may work better on the inorganic materials in the melt compounds. I am out of my element there, perhaps a snow belt operator can comment.

In my situation where it is cold but not snowy, the high ph on first pass is going to help with paint cleaning of road film when conditions are tough. Car bodies are cold and will absorb a lot of heat from the presoak. You can really pour the alkalinity to a car without much worry. I am more cautious in the Summer with high ph presoak, but usually respond to those conditions by just turning the presoak heat off when it starts getting in the mid 80s. Also, in the Summer the low ph as a first car kind of buffers the car.
 

wash12

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I have fought this hi/hi - lo/hi since opening, I have gone in circles with this and as of now I am convinced a touchless will clean a clean car but a dirty car needs brushes to truly clean it. The most frustrating thing is watching a car leave and you can swipe your finger on the car and see a layer of film being removed.

I am running blend co at 47 drops on a 2 step as follows- hi dwell 8 secs then hi again dwell 19 seconds, I feel like this is the best cleaning I can get so far but it isn't cheap running it this hot.

Per Greg advice, I did a spray bottle text, mix your solutions to the strength you are running in the wash and spray on car and see how it cleans. I found the acid to really do nothing in removing dirt/film and found the hi ph to do all the work. I know acid is supposed to clean the windows better but I don't see a touchless actually removing an eyebrow unless your burning it off with HF or something along those lines and even then I still think it needs friction.

I am somewhat of a perfectionist and not producing a clean car really pi**es me off, if it wasn't unattended wash I would go friction 100%.
 

natek10

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There are two ways to produce a clean car with a two step cleaning process.

The other way is to use a non-aggressive low pH that will thin the oily road film and allow the aggressive high pH to break the film, lift it from the surface of the car and allow the high pressure rinse to deposit it in the car washes pit. This works because the high pH bonds with the oil in a process known as saponification. The trick with this process is to thin the oily road film enough that the high pH can lift it from the surface, because it will still bond to the film even if it can't lift it. When it works you will get clean cars with very little damage. When it doesn't work you can make cars look dirtier than when they came in. While this doesn't do a lot of damage compared to the other way of cleaning it will swell o-rings and cause injectors and check valves to fail. This form of cleaning produces shinier cars but makes drying more difficult.

We are having this exact issue. What's the fix to this? We have played with different titration amounts on our lo and hi and still can't get it. Thoughts?
Thanks
 
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