How do you flush a blower on a CDS system?

[Bob Foster]

People recommend this and I don't have a clue what the correct way of doing this is.
How often and with what and how?
Thanks for everyone's two bits!

 

[John Watson]

Ya stick in the hose an turns the water on, Jeese, these guys from Canadia.

It is best to do it after you cleaned your tank and filter to your blower and after you have had an accidental foam over flow from your almost full waste tank in your clients driveway.

Run eng about 1000 rpm and slowly spray water into your blower inlet from inside your waste tank. Too much water at once on a high rpm blower can break a shaft. Been there had an employee who done that... Best to park truck blower exaust over drain. Run blower 5-10 minutes after flushing for air to dry internal parts. Inject spray of WD 40 or other water displacement fluid before shutting down machine.

 

[Shawn Forsythe]

Mr Watson,

Permit me to play devils advocate for a moment.

What say you to the premise that water flushing of the blower on a typical HM CDS unit is a quick way to clog the salsa HE.

 

[John Watson]

Shawn, you are correct, and incorrect I believe , A typical CDS unit till recently didn't have a salsa unit on it and I and my unit are old and ain't got no salsa unit or chips for that matter and My unit came from North of the Border in Canadia not Lynnwood or Muckalteal.. I don't know a thing about how their salsa units are made or plug up. Common sense tells me if hot air is to pass through and transfer heat there must be the same route for the cleaning water to pass. If not maybe there should be!!! My unit runs 200 - 230 degrees on the gauge at the HE Goot nuff for me..

Now pull your horns in and tell us how it is supposed to be done???

 

[Shawn Forsythe]

If you are really needing to clean the blower, would it not presume that it is filthy?

My greater contention is that if your blower has enough buildup to warrant flushing, you have a bigger problem than a dirty blower.

I guess my customers were rather spoiled. Thousands, and not single blower needed water flushing.

 

[Bob Foster]

My understanding from reading previous posts that periodic flushing the blower is part of good preventive maintenance program. I still don't know how this is done or if it should be done.

 

[Shawn Forsythe]

Periodic blower flushing with water is akin to a "home remedy" that many users practice outside of any manufacturers reccommendation to do so. In general, it is a practice that you can "get away with", but the actual benefit is going to be varied. A well designed TM, along with dutiful user maintenence never needs water blower flushing. As such, you will see both sides of anecdotal beliefs of the practice.

On the one hand, you will have a group who will say, "I always have flushed my blower, and never have problems, but I used to before I did". On the other hand, you will have a greater group who will say they NEVER flush their blower, and they never have a problem.

Some truckmount systems are engineered quite poorly to keep contaminants out of the blower. Some users exacerbate the problem with their daily maintenance practices, either not properly doing end-of-day blower rust prevention, or using the wrong "lube" products which contribute to residue buildup.

Flushing the blower with water may indeed help in these situations, but in my estimation, prevention is a far superior remedy to practice beforehand.

If you flush the blower, take care that you do not load the blower with too much volume of water, as the blower and the drivetrain is not designed to handle the density of liquids very well. A dribble or mist of water is best.

As well, make sure the process is thorough. You don't want contaminants coming to rest in the blower exhaust or silencer, which would cause corrosion. Afterwards, run the unit for several minutes to completely dry the blower and the exhaust system.

As I alluded to before, HM CDS systems are often outfitted with a ablower exhaust heat exchanger, or salsa package, which contain very fine "radiator-like" fins which can become clogged over time. The older HM units are more prone to problems, than newer ones. HM used to outfit units with a very fine HE unit, which was very good for heat conduction, but eventually became clogged with fine particulates and lint over time. The newer HE units are designed to better cope with environmental contaminants, but flushing the blower can present unique problems, Especially if the afformentioned maintenance issues have actually caused contaminant and residues to build up. "Unhooking" the salsa exchanger for blower flushing is not a trivial undertaking, and may be something you do not want to do yourself. Therefore, yu have to ask yourself whether routine flushing is really necessary. If it is, you may want to take steps afterwards to never make it necessary again.

 

[Matt King]

I know some guys do it. And hey, if it's working for ya then keep on doing it. It's all good... If you Do flush the blower like that be sure to dry out your silencer extremely well. Nothing worse than a puddle of water sitting on the bottom of your silencer just rotting it away. That is of course if your silencer isn't made of stainless which most aren't. Some silencers have plugs on the bottom you can unscrew to drain excess moisture. However, I've cleaned carpets since 1993 and have never flushed out a blower with water, soap or anything else. I've never had a single problem related to 'gunk' buildup on the blower lobes. If there was a problem the lobes would most likely bind up pretty quick. Those are very tight tolerances and anything that 'could' or 'may' build up in an area of concern would most likely be scraped or burned off while the unit is running. The key IMO to proper internal blower maintenance is to keep the blower lobes dry and rust free. I use CorrosionX for this at the end of the day. I have a blower I took apart a week or two back that has over 9000 hours on it. I never flushed it out and it still looked perfectly fine on the inside... just my 2 cents.

 

[Bob Foster]

Thanks for the learned response from everyone. I really don't think I need to or should rinse the blower. But Shawn you brought up an excellent point about what kind of spray lubricant is the optimum for a blower. I use WD40 with a 2 or 3 second blast.
What you everyone suggest as the best lubricant and the lenght of blast.
Thanks again!

 

[Shawn Forsythe]

CorrosionX, like Matt mentioned.

The physical attributes make it a perfect choice.

Awesome rust inhibitor. Excellent water displacer. Very thin film, low residue, no build up.

5 seconds-every day, ought to do ya.

 

[406]

if flushing the blower with water aint doin anything "good" for the blower then, spitting rust inhibitors in aint doin anything either. maybe we should just leave the thing be. i flush my blower with a water hose mabe 3gpm. this is done prior to the blower running for a long period. Shawn i think flooding the blower periodicly is good for it, i dont see the benifit of trickleing water into it, believe me, blowers can handle high water flow for reasonable periods. if someone thinks they should not flush the blower.....my test is when i shut down the blower, the blower slows itself down. listen to the blades winding down slowly or quickly. anything you put in the blower will be short lived.

 

[Shorty]

Now I'm really confused.

All this time, I thought those blower type vacs; were air displacement vacs;

And water should be avoided from entering them.

The WD-40 was to lubricate, and evaporate any moisture in the vacuum.

My vacuum pushes a lot of water out every day.

But then again, it is a liquid ring vacuum, meaning it needs water to create the vacuum.

No water = no vacuum.

Cheers,

Shorty.

 

[Matt King]

The lobes are cast iron. The air pulled through the blower from the hoses/wastetank is moist. Moisture+cast iron=rust. Thus the reason for CorrosionX. At the end of the day you want the lobes to be Dry. As a precautionary measure most guys (myself included) squirt a shot of C.X. or an 'equivalent' spray in the lube port to coat the lobes. It's especially important if your machine will be sitting unused for an extended period of time such as over the weekend. Some will say they've never sprayed anything into the lube port. That may be true. They may have been fortunate enough to not have a blower rust shut on them. Most likely they had the unit dry enough to where it never caused a problem. Nothing wrong with that.... I'm just one of the 'Better safe than sorry' guys.

 

[Greenie]

Better safe than sorry is just it, show me a blower lock up over a weekend, and i'll show you someone who didn't air it out for a few mins. at the end of the day.
I truely beleive most of the miracle of "spraying something" has just as much to do with paying attention to your system for a few mins. a day and actually running the blower dry as it does the actual magic juice sprayed into it.

Also keep in mind, the original purpose of a blower was a Water Pump, not an air pump. But we've come a long ways since then :wink:

 

[406]

we all have our memories of blower problems and ways to solve them. my logic is, rust inhibitors are great on CLEAN metals so, coating any blower with an rust inhibitor will not hurt, that said, most blower blades are coated with gunk, it just seems like it is doing very little to nothing. flooding the blower with just water is atleast taking a thick layer of gunk off of the blower blades. overspraying the blades with some lubes can lead to a cease up.....i have done it. i think most could probably get away with never putting anything through the blower, even after an overflow. at the end of the day, just running the blower open with the lid and filters off will atleast lower the humidity level in the blower

 

[Tom Mock]

Where do buy Corrosion X? Is this something I can get from an auto parts store?

I have been using PB Blaster. Any problems using this product?

Thanks!!!!

 

[Matt King]

I think Ace hardware stores carry it now. I get mine from Monte there in Omaha. I'll admit to being a tad over cautious.. I've gone from one extreme to the other over the years. I was once about as careless as one could possibly get... Not just in CC'ing but in life period..lol Greenie's right on the 'Air it out' thing. It should always be first and foremost on the 'end of the day' list. Get the blower lobes nice and dry. Open up those ports and let it pull air through while it's nice and warm still. Whatever ya do, do it well. How's that :wink:

 

[406]

when i think a little more, the airing the blower out probably, if the recipe for a seizing blower is there, drying will probably speed up the seizing process. i really am guessing, its been over 17 years since my last seize.