Procedure for acid flushing and pressure flushing

[sastanley]

hahaa....sounds familiar..on the side plate part anyway...I have the old not-welded bracket on my side plate, and that bolt has been up-sized one from the stock size..i am waiting for it to fail and need the cool little stud kit from Moyer

[Administrator]

When I get some time, I'm gonna post some pics and a thread about my "Replace the Alternator - oops! replace the Accessory Drive - oops! turned into replacing the Water Jacket Side Plate - Oh NO! Broken Bolt - Oh #@$!! broken Drill Bit!!! PROJECT"...

Jerry, my equivalent was offering to repair a leaky faucet during a visit to my Mom's home many years ago. Cost me about $1,200 and the admiration of a mother who had previously thought her son's engineering degree something to be proud of.

Bill

[Asa Kirby]

Hi roadnsky,

Your pictures are excellent! It definitely gives me something to aspire to. I've already implemented your suggestions and removed my 6" nipple and replaced it with just a pipe plug. Happily, I've included all the brass fittings into my own flush kit for future use (and by future, I mean when our marina here in Austin, TX decides to re-plumb city water to the slips.)

Thanks Again!

[sastanley]

So Jerry,

What is your procedure there with all those fancy fittings? Do you hook up a hose to each of those fittings at the same time, or are you doing one at a time, or does one end drain overboard into a bucket so you can see all the stuff you got out, or what?

Do you blast the block with fresh water thru the nipple or sideplate and collect it at the thermo housing? Same with the manifold I assume...in one end and out the other?

[roadnsky]

So Jerry,

What is your procedure there with all those fancy fittings? Do you hook up a hose to each of those fittings at the same time, or are you doing one at a time, or does one end drain overboard into a bucket so you can see all the stuff you got out, or what?

Do you blast the block with fresh water thru the nipple or sideplate and collect it at the thermo housing? Same with the manifold I assume...in one end and out the other?

First time I heard plumbing fittings called fancy!
Yeah, you nailed it.
The 6" nipple (I love writing that word!) has a ball valve (yeah that is fancy) on it so I can "blast" the fresh water thru.
(Luckily, my marina has really good pressure on our fresh water supply.)
Anyway, I flushed out the aft water jackets (3& 4 cyls) then move to the forward block drain and do cylinders 1&2.
The crap exits out the Thermostat housing (the thermostat is removed) thru a hose to a bucket that I filter to see what I caught!
Then, finally I move to the manifold. Intake forward and output is aft.

In the pic, the GREEN hose is the incoming pressure water. The CLEAR hose is the outlet hose going to the bucket.
You can see the crud thru the clear hose while you're doing this. Sorta like a "colon blow" for the engine...

Also, while I had the thermostat out I cleaned it up with vinegar and did the hot-water-in-the-pan test.
Kinda like being in Jr High Science class again...

[sastanley]

roger thanks! More good pics

Ok, the Admiral is hollering at me so I'd better get - "what are you doing at the Moyer site, I thought you were going to work on the mast today?"

[Baltimore Sailor]

I've been reviewing this thread the last couple of days, and I had a thought: getting at the front (closest to the flywheel) 1/8" fitting normally requires the starter to come off. Why couldn't a flexible line be used there that had 1/8" fittings on both ends?

A quick Googling finds an $8.99 18" grease gun hose with 1/8 male NPT threads on each end. The line has a rating of 3000 psi, so I don't think we need to worry about our marinas' water pressure bursting it. Yet it should be flexible enough to get into that fitting with the starter still in place, and the rest of the bushings, etc. could be fit to the other 1/8 male fitting on the end.

Unless someone can think of a good reason not to, I'm going to give this a try. I just acid flushed the engine -- and good golly, what a mass of goo came out of it -- and I wanted to do the pressure flush as well. This looks like a good workaround for removing the starter.

[roadnsky]

You'll need the fitting/hose connection at the point where it screws into the engine to be in the 2-3" range before it makes a hard angle.
(Looking at pics I have it appears to be about that much clearance between block and the starter)
Could work though.

Another thought would be a 90° fitting there?

If you do it, be sure and let us know where you end up.

[Mark Millbauer]

Last time I did the acid flush/pressure flush I was able to install a brass 90 or 45 in the flywheel end coolant drain. I don't remember which it was and don't. have pictures but it is still there with a 2" extension and a cap on it. remove the cap and it will drain. Or attach the hose to flush. Works great. it was a bit tricky getting it threaded in but only took about 5 minutes.

Mark
C27 'Solution"

[Baltimore Sailor]

But you had to take the starter off to get it on there in the first place, right? My plan is to never have to take off the starter at all.

I may give it a try this weekend, depends on the weather. Saturday is looking good, so it'll probably be sailing instead of tinkering. Maybe next Wednesday, which is my usual maintenance evening once the light goes away.

[roadnsky]

BS-
I did a measurement yesterday and you've got just over three inches between the starter and engine block.
Good luck. Let us know...

[Mark Millbauer]

I did not have to remove the starter. Again, it was tight but I was able to get the elbow installed (little by little)with an open end wrench. There are probably some brass elbows configured better than others for this, location of wrench flats, over all outside dimensions, etc. I just used one I had on hand.

Mark

[JOHN COOKSON]

Acid Flush With Vinegar?

Can I use vinegar to (successfully) acid flush my A4?
If so how long should I leave it in the engine?
Would leaving it in for a week be detrimental?

Thanks everybody.

TRUE GRIT

[roadnsky]

Can I use vinegar to (successfully) acid flush my A4?
Yes. It's a little less effective, but yes, you certainly can.

If so how long should I leave it in the engine?
I leave it for 24-48 hours.

Would leaving it in for a week be detrimental?
No, not really. I'd think after about 2 days though, you're not getting any more positive results.
If you're gonna do a week, do 2-3 treatments during that timeframe.

[Baltimore Sailor]

I must say that I've done both the vinegar flush and the muriatic acid flush, and the muriatic flush was by far more effective.

This is how I did it:

I got two 5-gallon buckets. I mixed up a quart of muriatic acid to 4 gallons of water. The sticky says 1/3 of a gallon to five gallons of water, but that's just a 1:15 solution, and if you use 1 qt in a 1:15 solution you get a total of 16 quarts, or four gallons of total solution.

I rigged the other five gallon bucket over the stern with lines to keep it right at the exhaust output. When I started the engine I waited a few seconds before putting the bucket under the exhaust to make sure I was catching solution rather than just water. I thought about using red food dye in the acid solution so that I'd know when it was coming through, but I forgot to bring it along. Still, it was pretty obvious when the solution starting coming out, as it was awfully dark and nasty.

A box of Arm & Hammer baking soda is one pound, so I put half the box in my first catch bucket to neutralize whatever came out of the engine. A good thing I did, too, as when I was done pumping in the solution and brought that bucket inboard, it was boiling and foaming like crazy as the soda neutralized the acid.

As the solution sat in the engine, I brought the first bucket inboard and set it aside, then rigged the bucket I'd used for the solution as the second catch bucket, after first dumping its dregs into the first catch bucket.

When I fired up the engine again, the outflow was if anything even darker and nastier than before, but by the time the bucket was getting near full the outflow had cleared up to where I thought the flush was done.

I ended up with two 5 gallon buckets of the nastiest looking water I'd ever seen. There was no way I could just dump it into the creek. What to do?

Luckily, I'd read up on the reaction of baking soda (NaHCO3) and muriatic acid (actually a 30% solution of hydrochloric acid, or HCl), and it goes like this:

NaHCO3 + HCl ->
NaCl (table salt) + H2CO3 (carbonic acid) ->
NaCl + H2O + CO2

Basically what I had was a very fizzy salt solution and dirty water. I dumped it into a toilet at the marina, so that it would go to a water treatment plant where they know what to do with salt water and dirt.

The only downside of the entire procedure is that muriatic acid is nasty, and actually smokes when you open the bottle . Mine came in a plastic 1-quart bottle like bleach. It was much nastier than bleach to behold.

Still, if you dump it into the 4-gallon bucket of water and keep your face upwind, there's no problem. Once it's into the water you're OK, but I'd still keep my distance from it as much as possible. Seems to be pretty active even at that dilution.

All in all a pretty simple procedure, as long as one is careful. I think it's a lot more effective than the vinegar flush, too.