Best media to use for an intake manifold?

[Heo]

 Lars, no machine shops nearby so it’s all on me

Then whats left is some "kitchen work" when the wife is out
of the house...

Serously i thought of puting an old dishwasher in the shop
to wash parts in

[Joe-JDC]

One thing that hasn't been mentioned about glass beads is that they break under high pressures and we all know what glass does to your flesh when you bring the two together under pressure.  Also, broken glass beads imbed themselves into aluminum and make it nearly impossible to remove all of the broken shards, even with high pressure washing.  I quit using them years ago when I found them embedded in oil residue under the traps in my oil pan.  Sonic cleaning won't get them all.  Glass beads work well on suspension pieces, brackets, and anything that doesn't involve the inside of the engine.  My experience with walnut/pecan shells is that they are difficult to get small enough to use in a nozzle without clogging up easily, and they close over pores in the metal rather that remove contaminants.  Your experience may vary.  Joe-JDC

[fekbmax]

A good degreasing then aluminum etching cleaner and a good cool water rinse.  Makes heads, intakes, transmissions, look new. If it's really badly oil soaked muriatic acid works well.

[blykins]

Soda....

Here's some parts that were recently soda blasted:





You don't have to worry about it....a quick wash and water will dissolve anything left inside. 

[chilly460]

Good topic.  I recently had an intake powder coated, they told me they tape up all ports but I'm guessing it broke through the tape and there was sand residue inside the intake.  I scrubbed it with bottle brushes as best I could several times and ran water through it, but being a dual plane there were definitely places that didn't get scrubbed very well.   

I'll avoid the agita going forward and will use walnut shells. 

[FERoadster]

Since I've got a number of intakes to blast I plan on making some wood patterns that duplicate the head shape and use an intake gasket to seal the ports. Minimal clean up on the head surfaces would be needed  but no blasting material will get into the ports. Now to figure out media.

Where is a good source for soda to use as material.

Richard >>> FERoadster

[cjshaker]

Even with ports taped up, you still have to be leery of the bottom sides of the intakes. Especially with some less than ideal factory castings that have porous spots. They can hold the media and release it later. I wouldn't try it on anything that had porous castings. Modern castings with good quality sand cores, like Edelbrock always seems to have, is less of an issue.

[babybolt]

Plastic media has worked the best for me.  The part should be cleaned first.  The aluminum wheel cleaner stuff does a good job by itself on an intake.

Walnut shells seem to take forever to clean.

Tried soda, but it just made a big foggy mess inside the blast box, but then maybe the cabinet needs to be modified to use soda.

[machoneman]

https://www.harborfreight.com/50-lbs-medium-grade-armex-soda-blast-media-65929.html

Since I've got a number of intakes to blast I plan on making some wood patterns that duplicate the head shape and use an intake gasket to seal the ports. Minimal clean up on the head surfaces would be needed  but no blasting material will get into the ports. Now to figure out media.

Where is a good source for soda to use as material.

Richard >>> FERoadster

[gt350hr]

   Blue Thunder uses crushed garnet. He is very particular about the finish on his parts. Glass beading was a serious problem for Bud Moore(rip) in '69. They blasted a bunch of parts and had instant failures on the dyno when testing the engines.  They stopped doing it immediately. Steel / stainless steel shot is better but still requires careful cleaning / air blasting afterward.
     Randy

[Drew Pojedinec]

Oddly enough I have 200lbs of baking soda. My wife bought it when Walmart had some sorta sale, dirt cheap like .018 a lb.

I’ve done factory iron intakes but never alumin with it.

Current plan is to soda blast it and see how it looks. If it’s good I’ll rock on.
If not I’ll get some walnut shells or something and try that out.

I do NOT use soda in my cabinet, I typically take the part out into the vegetable garden and blast it there with a small handheld unit. It wastes a lot but whatever. Think it takes me ten lbs to to an iron intake perfectly.

[Drew Pojedinec]

Coooool crushes garnet. Nice. I figured it’d be too hard. I might try that out.

[Heo]

N/M

[scott foxwell]

No aircraft engine manufacturer or authorized rebuilder is allowed to use any glass beads.

An AEC tech bulletin (one I could not copy as a PDF here!):

Title: Dangers of contamination from Glass Bead Material

Technical portions are approved by Airmotive Engineering Corp.
T.N. No.: 09-2
Page: 1 of 2
Issued: 2-10-10
Revision: 0
1.0 PURPOSE: To help prevent engine failures
2.0 SCOPE: To alert technicians and mechanics about the perils related to glass beads
3.0 APPLICATION: Maintenance of aircraft piston engines.
4.0 REFERENCE: Engine Manufacturer’s overhaul manuals and service bulletins, service
instructions and service letters (Continuing Airworthiness Instructions) should always be
consulted as the principal authority for any engine overhaul and maintenance information.
5.0 DISCUSSION: One of the methods used by technicians and mechanics to clean component parts
is to shot blast using glass beads. This procedure has some benefits over other cleaning
procedures, but all of the benefits pale in comparison to the devastation that glass beads cause
when they are introduced in any manner into the inner workings of an aircraft piston engine. Even
one glass bead can cause significant damage before it breaks up into glass dust. If it is trapped in a
bearing it does its damage and then can re-circulate to do some more.
Many shops keep glass bead blast media and only use it to clean external parts. Others believe
that proper cleaning will eliminate the hazard. There are two axioms that should be posted in
every engine shop:
1. If glass beads are any where in any quantity in an aircraft repair facility, they will end up
in aircraft engines!
2. The only thing that loosens up and moves glass bead media from the nooks and crannies
of aircraft engines and into areas where they cause the most harm is hot engine oil!

Most engine overhaulers or repairers have experienced problems related to glass beads. However,
many were never aware of the root cause for their problems, and either gave up on the search for a
cause or attributed the cause to something else. This is because glass beads will defy cleaning
efforts and are difficult to identify after the damage is done. Airmotive Engineering Corp. and
Engine Components, Inc. have experienced the problems caused by glass bead blast media many
times over the years. Because of these experiences (i.e. warranty claims), our technicians have
developed highly effective evaluation techniques, and it is rare that positive evidence of glass
beads cannot be found.
T.N. No. 09-2
Revision 0
Dangers of contamination from Glass Bead Material
Page 2 of 2
 The photograph below shows glass beads that were solvent washed from behind piston rings of
cylinders sent back to ECi for warranty consideration. The pistons, rings, cylinder bores, and
bearings were severely damaged and unserviceable.
Photo 1: Glass Beads in Engine Oil and Solvent

6.0 Conclusion: It is of utmost importance that glass beads not be used in any manner to clean piston
engine parts. Even one glass bead can cause significant damage, and failure to comply with this
instruction will result in denial of a warranty cl

Re: continentalmotors.aero/xPublications/xService%20Bulletins/ECi%20Archives/09-2/

I rest my case that unless one can almost surgically clean, even an intake, from 100% of all glass beads, other media is preferred.

You really can't compare Continental covering their ass from a liability standpoint with cleaning an intake for a Ford FE engine. I think that's a little of a stretch. Not saying glass bead won't hurt anything and of course, thorough cleaning is necessary but we're not flying airplanes here. I'll tell you this afa aircraft...walnut particles killed 26 people in Manheim, Germany when a CH47 fell out of the air at an airshow. Walnut particles grounded every CH47 on the planet for a time till they figured out what the heck was going on. Long story short, due to insufficient cleaning, the particles plugged an oiling manifold on the main (rear) transmission output shaft causing a bearing failure which allowed the drive shaft that connected front and rear rotor gear boxes to run-out and cut itself in half. No power to front rotors, rotor blades collided at altitude.
Point is, no matter what media you choose, a thorough cleaning is mandatory. Chemical cleaning would be safer.

[HTM101]

Here's my intake manifold cleaning process:
a. 1st blasting is with stainless steel grit for initial cleaning.
b. 2nd blasting is stainless steel round shot, average size .004-.007" diameter, for peening and lustre.
c. Washing with 13 HP pressure washer; 25 degree nozzle pattern, 3500 psi and 4 gallons per minute of water.

All of those steps take a lot of time, and then the finished surface is easily stained once in the engine bay.  I decided to powder coat the tunnel wedge intake, and the pair of Blue Thunder competition valve covers.  I used a 5% low gloss clear powder coat and the result was excellent.  Now all that's necessary to clean off finger prints, drops of sweat, oil mist and dirt is a shot of Formula 409 or something similar and a paper towel.