Aluminum Cylinder Head Cleaning

[Careless]

Hi.

 

I just got my cylinder head (RB, though) and this is the most popular head forum on the site, so I'm posting here so many more people can comment and give experienced answers. Sorry in advance to those who may object, I just find it makes sense to post this info here since more will see it.

 

I've been prowling the web and other boards for methods on a TOTAL aluminum head cleaning.

 

Does anyone have any good ideas on how to fully clean an aluminum engine head without using damaging solvents? The cam bores on the RB engine heads are VERY critical in that a scratch or two can render the entire head useless (because you can't order the cam caps separately).

 

I was advised to get a big metal tub, fill it with distilled water, and boil the head with a propane heater from underneath until all the soot and carbon deposits free up from the exhaust ports and become part of the water.

 

Are there any other methods of getting inside EVERY nook and cranny of the head so that it will facilitate porting and modifying the engine head with no worry of missing anything minute due to cover-up by dirt?

 

Lets here it!

[Mayolives]

I believe it was John C that recommended using Simple Green and a five gallon bucket. I submersed one end of a P90 into it and the other end the next day with very good results. After the bath I rinsed it with water.

[johnc]

I don't think I recommended that but its a good idea and a good first step to get the big stuff off. A very mild etching cleaner works great;

 

http://store.weldingdepot.com/cgi/weldingdepot/DF781-4X1-1.html

[Tony D]

Why would line-boring RB Cam Bores be any different than any other line-boring operation? At worst I would think you would weld into the lower seats to restore proper height, and then line bore till true on original centerline.

(Just came first to mind when the comment about 'rendering the head useless' was broached.)

 

What I used was a Military Chemical that all I can remember was 'Jet Engine Oil Gas Path, NOI'---it was a amber liquid that when mixed with water gave a white appearance, and was injected into the front-end of jet eninges while running to clean the blades.

 

When used full strength, it would clean grease and grime off aluminum parts like nothing I've seen...and would not turn them black or corrode them. When you had done your scrubbing, you simply washed it off with water.

 

I posit there is 'simple green' that is not green, that I used at the Natural Gas Company that had similar effect when used full strength. I do know that run of the mill simple green put into either a steam cleaner, or hot-water washer will STRIP aluminum parts CLEAN to bright silver looking without much effort as well. My son was amazed that we cleaned off all the encrusted gunk and grease from his L20B using simple green laid on full strength and simply brushed to loosen the hard baked on stuff, then pressure washed off. Later that day we did an LD28 using the steam cleaner injecting full strength simple green and it did the same job in about 20 minutes of spraying, instead of three hours of scrubbing and working it by hand. I would assume leaving it submerged in a vat to let the chemicals do the work with some slight mechanical agitation would work well.

 

They sell hot-pressure blasting cabinets now that will put the head on a rotisserie in the center, and blast at 750psi with nozzles, a water based solvent that will clean everything off but QUICK! You can do the same with a bucket of HOT water, simple green, and toothbrushes right at home....it just takes persistence and time.

 

 

For blocks I have used easy-off mild lemon scent (no gloves formula) for years to remove baked on grease. JUST DON'T GET IT NEAR ANY ALUMINUM!

[1 fast z]

Get ahold of a local Engine supply house, and get what is called CITRIS SOAK. Thats what we use in our alluminum Hot tanks.

[Mayolives]

QUOTE: Avoid using a citrus based degreaser on aluminum. A simple way I've degreased a head is to mostly fill a 5 gallon bucket with Simple Green and stick the head in the bucket for a couple days, turning it 180 degrees on day 2.

__________________

John Coffey

johnc@betamotorsports.com

BetaMotorsports, LLC

[1 fast z]

The Citris Stuff I am talking about is purely for alluminum. It makes a head come out of the tank, looking like it was just sand blasted, and does not etch the metal.

[Careless]

SimpleGreen has warnings on the label that state not to have it come in contact with aluminum parts for long periods of time...

 

so is it safe?

 

TonyD, I'm not sure why one couldn't align hone the cam bores, but nissan does not sell the caps individually, so in the even that that align hone goes wrong... will I have to put bushings of some sort?

[Careless]

hmmmm... I wonder where i can get some Mirachem 500 in Toronto.

[johnc]

I guess I did post the Simple Green suggestions. The caution against using Citrus cleaners and Simple Green is generally for discoloration, not damage or etching.

[Tony D]

Generally when a cap or seat is galled from a seizure of FOD ingestion, the common practice is to simply clean and grind out the affected areas, heliarc in replacement alloy to be proud, and then line-bore indicating off undammaged bores on either side, or better still off a blueprinted dimension with the head jigged in appropriate machinery.

 

Older cylinders heads have been repaired this way for years. On L-Engines the bores can be turned oversize and bushings manufactured and shrunk/staked into place. Then you simply punch your oil holes in as required.

 

If the boring procedure goes wrong, you simply reweld, and re-index and do it over. It's aluminum...you just add more! LOL

 

In the VW Industry, there are a load of cheap tools that clamp into the main bearing and cam bores for various turning operations powered by an air drill motor! Many of these tools revolve around cutting bearing diameters larger in the center mains for Type IV bearing/jounral use on custom cranks, or double-thrust face bearings being installed on the camshaft bores instead of the 1/2 face that stock employs. Ideally you would do these things on a mill with a nice rigid boring bar, but a couple of bearings with a moveable boring head cutter and an air drill and many people have made/saved/reclaimed a 'thrashed' VW case that the OEM said was a 'use it and throw it away' kind of part. And that the tooling STILL exists to this day when the cost of a whole case assembly is only around $349 is a testament to people who want to keep what they have in operation and not buy a new part.

 

OEM's are notorious for not making fixes available cheaply. The Aftermarket will fill that niche soon enough. And if you have a good machine shop, that kind of repair should be no problem. It's all a matter of how you phrase the question many times.

/Threadjack Warning/

"We Digress"

LOL

[Careless]

thank you for your explination tony.

 

I know things can be line honed it's just the fact that RB26 heads are so hard to come by.... I mean I only ever found like 2 other RB26 heads in Toronto, and the rest were attached to 4000 dollar engines.

 

I really want to be careful and minimize any machine work done to the head because I decided to choose a corrosive degreaser.

 

Another worry are the lifter bores, as they are pretty deep in there, and just a bunch of worrisome parts that I'd rather not have an inexperienced person go in and touch and then say "ahhhh it'll be fine" when their clearances are off by what nissan states in their FSM, or whatever.

 

Ordering oversized lifters is a possibility, but only if I have to. I mean... 24 bores to bore, 24 lifters. 6 cam caps x 2 for cam clearancing via line-hone... 150 - 300 for a line-hone on mains = a lot of money to spend because I used a corrosive cleaner.

 

So who can honestly say that SimpleGreen will not marr aluminum, because the 4AGZE thread that had the pistons soaked in simple green stated that the pistons were no longer usable. I put some simple green and a couple of drops of water in the combustion chamber, with a spark plug to block from draining, and this morning it was brown, but there are still a lot of carbon spots. No corrosion evidence because the surface is rough anyway, and not like that of a lifter or cam bore.

[Tony D]

Cam Bucket Bores can be sleeved as well.

 

It all depends on how much money you are willing to spend to keep an engine or part from being 'scrapped'. If the engines complete are $4000, then spending $1500 to have everything blueprinted and line bored/sleeved back to specification may be worth it if the heads are not available separately for a considerable discount. We're talking about costs to recover bores, if you do one or two that shouldn't exceed $100 each. And if this cap or that were to be damaged, similarly you can index off the undamaged bores and repair one or two for a similar ammount.

So $400 to reclaim something that might otherwise be considered 'scrap' is probably even economically viable even if the heads are available for a comparable price---you end up with a head you know has been checked and that everything is to specification for that repair price...not simply getting a 'it ran when I disassembled it' used part.

 

I will check with some of my military friends on that gas-path cleaner. We would literally leave carburettor bodies in that stuff over the weekend without any damage. It's very mild even in fully concetrated form.

 

If you have ever seen Amway LOC, that is kind of what it looks like, but I don't know if that is the same thing or not. (er...or the Canadian Equivalent of Amway LOC...)

 

Obviously preventing etching from occuring is a concern. My comments are more geared towards a repair to a head that had something happen like a cam break, or lost oil pressure and seized this component or that. There is a point where reclaiming it may simply be not feasible.

 

http://www.zok.com/products/products.htm

http://www.turbo-k-direct.com/productinfo.htm

http://www.macraesbluebook.com/search/product_company_list.cfm?Prod_Code=1799550

http://www.enginebuildermag.com/Article/2225/aluminum_cleaning_a_small_shopx2019s_perspective.aspx

[Careless]

Hi Guys,

 

I figured I'd get some simplegreen max because that's what I've been using, so I got a rubbermaid tote, 2 bottles of the max, and 8 litres of distilled water so it does not rust any of the head parts that may be iron or steel or whatever else.

 

I also bought a steam cleaner that I used for about 10 minutes. I don't even think it was at max heat yet but it blasted thin films of oil off in seconds. I think I should have opened the garage door a bit more though! LOL.

 

good thing it's not toxic stuff!

 

Anyways, I have both heads off, and this was the one where the PCV valve shut closed just over the intake rockers, so they were sooty and varnished as if they were painted deep brown, yet the driver side valve train is bronzed with varnished and looks as if it were meticulously painted by the oil-film gods.

 

It seems as if its doing the job and hopefully it does not gall the aluminum, because if it does, I'm going to have no choice but to use some fine synthetic steel wool and just make them as smooth as possible and chuck the heads back on (moving back to my house, can't have the car in pieces, it's got to move!)

 

but so far, so good.!

[PalmettoZ]

Hi.

 

I just got my cylinder head (RB, though) and this is the most popular head forum on the site, so I'm posting here so many more people can comment and give experienced answers. Sorry in advance to those who may object, I just find it makes sense to post this info here since more will see it.

 

I've been prowling the web and other boards for methods on a TOTAL aluminum head cleaning.

 

Does anyone have any good ideas on how to fully clean an aluminum engine head without using damaging solvents? The cam bores on the RB engine heads are VERY critical in that a scratch or two can render the entire head useless (because you can't order the cam caps separately).

 

I was advised to get a big metal tub, fill it with distilled water, and boil the head with a propane heater from underneath until all the soot and carbon deposits free up from the exhaust ports and become part of the water.

 

Are there any other methods of getting inside EVERY nook and cranny of the head so that it will facilitate porting and modifying the engine head with no worry of missing anything minute due to cover-up by dirt?

 

Lets here it!

 

Hey-

Try EASY OFF oven cleaner. Works great. Use a tooth brush if you need to on stubborn spots, rinse with water. I just cleaned mine with it and a green scotchbrite pad.

[Tony D]

Easy Off is an Alkaline Cleaner, and DOES have the potential to harm aluminum. For the block and it's crud, it would be great, but I would shy away from it on aluminum. If you want to use alkaline cleaning you can make up a 5 or 10 gallon batch of cleaner using "Vanish" toilet bowl cleaner---really active cleaner for carburettor bodies, but you have to watch closely, or it WILL turn the aluminum and mazak bodies BLACK...and from there, the disolving begins!

[Careless]

Easy Off is an Alkaline Cleaner, and DOES have the potential to harm aluminum. For the block and it's crud, it would be great, but I would shy away from it on aluminum. If you want to use alkaline cleaning you can make up a 5 or 10 gallon batch of cleaner using "Vanish" toilet bowl cleaner---really active cleaner for carburettor bodies, but you have to watch closely, or it WILL turn the aluminum and mazak bodies BLACK...and from there, the disolving begins!

 

I Used Easy Off on the A/C mounting bracket and the tensioner/pulley bracket and it burned the soot and crud off it immediately. I then painted them silver on one side, and will be finishing the other side tonight. They're not even visible, but I figured I might as well to prevent corrosion.

 

Tonight, I'm going to lift the manifold out from the driver side of the

engine bay and spray easy-off on the engine block and use a wire brush to remove all the loose rust. There seems to be an insane amount of build-up on around the dip-stick tube. I hope nothing is severly pitted enough to break off.

 

And yah, don't use it on Aluminum. I think I'm going to mask off the pistons really well before I attempt to use it on the block.

 

[Guest jcushing]

simplegreen can etch aluminum. in the airforce were not allowed to use simple green to clean aluminum parts anymore. you would have to leave the simplegreen on the aluminum for some time i would imagine but it is possible.

 

look into soda blasting, its like sand blasting but it isnt abrasive enough to remove the top layer of aluminum like abrasive media can.

 

its something safe enough that you could even use it on the combustion chamber and not worry about it ruining valve seats etc...

 

heres an example of sodablasting a tranny (not mine) theres also pics of a head being dnoe in that thread somewhere

 

http://www.homemadeturbo.com/forum/index.php?topic=89170.200

[Tony D]

USAF stopped using Simple Green?

That was the 'latest and greatest' and was supposed to supplant PD-680 for immersion degreasing.

 

That PD-680 and "Gas Path, Engine Oil NOI" are the two biggest thefts I miss not being in the USAF any longer...LOL

 

That gas path stuff would do wonders on aluminum.

[Careless]

Yesterday night I bought a mall trash bin (8 Litres) and I bought some super-clean from walmart.

 

I put it in the trash bin and diluted it some. It works wonders.

HOWEVER, I'm glad I didn't use it on the head. Shortly after (1 hour) dunking my intake manifold into the solution, it started to clean really well, but it started to turn a darker colour...

 

Not really black, but like a film of a darker shade of grey. I immediately took it out and sprayed it with the last bit of simple green that I had.

 

What worries me is that I use it on my throttle body as well and that's supposed to be a tight seal. It is definately aluminum rubbing off because it keeps whipping off as a dark grey film onto any cloth I use.

 

I neutralized the throttle body with some dish detergant and simple green max bath/spray/scrape/brush.

 

Tonight I'm going to go buy more paint (stupid gold never looks like the cap on the spray bottle!) and get some more simple green max. Only problem is that I can't find larger quantities of simple green.

 

Raff