Author Topic: Fox .35 cleaning varnish (Read 5350 times)

DanielGelinas · « **on:** April 05, 2011, 05:42:10 PM »

How often do you clean your fox engines for varnish?

What do you use to clean the varnish off?

I only have 1 quart of 10-29% castor in it ant it already seems all gummied up

Thanks

-Danny

Paul Taylor · « **Reply #1 on:** April 05, 2011, 06:22:20 PM »

Search here... some guys use anti-freeze in a crock pot, but it stains the case.

My flying buddy turned me on to Dawn power dissolve soap. It too will stain the case a little but works well in the kitchen sink.

DanielGelinas · « **Reply #2 on:** April 05, 2011, 08:15:43 PM »

Thank guys, this is for the inside of the engine.
Ty, you seem to think all is well as it is?
In general, how often do i need to clean the varnish out? After 2 gallons...4 gallons...

Thanks,

-Danny

Jim Kraft · « **Reply #3 on:** April 05, 2011, 08:37:46 PM »

Some say adding a little synthetic oil to your fuel will clean out the varnish, and keep it clean. I have probably done a 100 engines in the crockpot antifreeze method, and never had one stain the case yet. I don't know what I do different. I have heard others say it stains the case also. Maybe because all of the engines I have done have been either Foxes, McCoys, or old spark motors. I have done a couple of OS FP 40's though, and no stains. I do use Prestone antifreeze straight, which is the old ethylene glycol.

Randy Ryan · « **Reply #4 on:** April 05, 2011, 08:44:57 PM »

I've had 1 McCoy case come out blotchy, bummer, it was a nice first model too. I also had the paint come of an ST .46, other then that I've had great success with the ol' crock pot and I use it in all my restoration work.

Castor gum on the piston. Depending on the wear of the piston, a tiny deposit around the top of the piston is maybe beneficial, but on the skirt it is not. As it warms it softens and causes drag and can even cause overheating. I'm not saying take it off or leave it, if the engine is running well, leave it alone, maybe clean the head if you feel its necessary.

jim ivey · « **Reply #5 on:** April 05, 2011, 09:19:39 PM »

the best thing i ever found was white gas it wont tarnish. tri chlor would work acetone leaves a chalky residue never tried mek that mght work. ya really ought to find someone with a hot-tank most engine rebuilders have them. they'd probably do it for nothin. oakite in the crock pot would also work. carburetor cleaner will also work well u can get that at auto-zone use an acid-brush for the tuff spots az sells them too. jim

DanielGelinas · « **Reply #6 on:** April 06, 2011, 05:38:58 AM »

Thanks Guys!

DanielGelinas · « **Reply #7 on:** April 06, 2011, 03:13:45 PM »

Can someone explain to me in a nutshell, the crokpot method please?

Thanks!
-Danny

RandySmith · « **Reply #8 on:** April 06, 2011, 03:41:52 PM »

Quote from: DanielGelinas on April 05, 2011, 05:42:10 PM

How often do you clean your fox engines for varnish?
What do you use to clean the varnish off?

I only have 1 quart of 10-29% castor in it ant it already seems all gummied up

Thanks

-Danny

Hi Danny

Dawn power dissolve soap..Stay away from this unless you take the engine completely apart and reoil it thourghly, Power dissovle is VERY corrosive and will make a mess of anything steel if left on for too long, It is hard on Aluminum too
You should not have to clean the FOX that much. I would use high oil content with part synthetic to keep it clean

You can read my engine article pinned to the top of the engine forum

Regards
Randy

DanielGelinas · « **Reply #9 on:** April 06, 2011, 05:01:20 PM »

Again, Thank you very much for the info guys

-Danny

Brett Buck · « **Reply #10 on:** April 06, 2011, 05:46:10 PM »

Quote from: Randy Ryan on April 05, 2011, 08:44:57 PM

I also had the paint come of an ST .46,

Paint on an ST46?

Brett

Randy Ryan · « **Reply #11 on:** April 06, 2011, 06:52:25 PM »

Quote from: Brett Buck on April 06, 2011, 05:46:10 PM

Paint on an ST46?

Brett

You betcha, all the older ST cases were painted silver, at least the .35s and the .46s I've had

Brett Buck · « **Reply #12 on:** April 06, 2011, 06:56:18 PM »

Quote from: Randy Ryan on April 06, 2011, 06:52:25 PM

You betcha, all the older ST cases were painted silver, at least the .35s and the .46s I've had

Hmm, I had 5 of them, back to the days of "red box" versions, and I never saw that. Learn something new every day!

Brett

Randy Ryan · « **Reply #13 on:** April 06, 2011, 08:30:58 PM »

Quote from: Brett Buck on April 06, 2011, 06:56:18 PM

Hmm, I had 5 of them, back to the days of "red box" versions, and I never saw that. Learn something new every day!

Brett

They are masterfully done, ST always had that extra special "finished" appearance, that how they did it.

jim ivey · « **Reply #14 on:** April 07, 2011, 01:01:04 AM »

Well ty, better tell Brett ro run over to 182 and tell em "quick get that hot tank outta here it's eatin up all those expensive missle parts "

Neville Legg · « **Reply #15 on:** April 07, 2011, 02:33:00 AM »

I just flush my motors out with lots of IPA, Isopropylalcohol. It must do something, because it turns brown when it comes out, more so on my 4strokes

Then just re-oil.

Cheers

Randy Ryan · « **Reply #16 on:** April 07, 2011, 09:36:32 AM »

Quote from: Ty Marcucci on April 06, 2011, 06:45:41 AM

Being a former engine mech, let me tell you about hot tanks; They EAT aluminum right now. Never put a toy plane engine in a full size engine hot tank. Gone in an hour or less. Guess how I learned this many years ago and it was a valve cover, not a toy engine. To clean a model engine, a crock pot with antifreeze will do the job.

I have never had a Fox run slow, even with varnish. If it gets on the piston skirt, some thing isn'
t right. Most of it is on the upper pasrt of the piston and only helps keep compression. Fox pistons adn some others of that ilk are very prone to wear. The varnish helps prevent this. They asre not ABC or AAC or such. Just mehenite (sp) or such..

Ty,

I didn't say they would run slow, I said that could run slow, I also said that if its running well, leave it alone. There's a limit to what it will tolerate. Best fit is without goo, but many will debate that. Me, being the me that I am, will buy or make new pistons if the congealed castor is forming on the piston skirt or even below the edge of the crown. I won't depend on a spend lubricant as a seal, its soft and expands at a different rate then steel or iron and there will come a time when it will effect the running quality of an engine. Sorry, its the designer coming out of me.

jim ivey · « **Reply #17 on:** April 07, 2011, 11:30:56 AM »

Ty : Sorry about being such an ornery old bastard. But I swear to you. That is a large sonic hot tank using tri-chlor to clean aluminum and various other materials, well it was in 1986. Its the chloride that would attack the aluminum and maybe cause some discoloration, given enough time. I'm not sure how long, maybe a couple of years. Even then I don't think it would cause parts to literally disappear.When processors would sometimes leave aluminum parts in the acid to long when etching for anodizing, like over night. they would sometimes look like a crinkle finish. Once a plater lost a rather expensive aluminum part I had made, he said he didn't, but about a month later his driver brought over what looked like a piece of charcoal resembling my part along with a letter of apology and a credit for future work which was 3x his original invoice. Now that was sulphuric acid! It still didn't disappear! My background was machine shop. I know a little about materials solvents , cutting fluids rct and what will or wont ruin a part. I am absolutely certain no aluminum parts would disappear in a hot tank. If the sulphuric acid didn't make it disappear in over a month. I'd stake my life tri-clor wouldn't either. aside from that I don't think the crock pot would hurt the engine, afterall you all do it all the time. I'm just against putting ferrous materials in water they will corrode or rust. That's my only objection. The carburetor cleaner is probably the best bet. I use Coleman camping fluid, its "white gas" or was. Its great for degreasing like on oil soaked balsa or motormounts. it'll suck that Castor right out and the glue will stick again. Do the same to that varnish. It may need a little help from the acid brush.I've never had an engine get in that condition. Some of mine ran for years in the same airplane. Jim

Randy Ryan · « **Reply #18 on:** April 07, 2011, 12:57:55 PM »

Quote from: jim ivey on April 07, 2011, 11:30:56 AM

Ty : Sorry about being such an ornery old bastard. But I swear to you. That is a large sonic hot tank using tri-chlor to clean aluminum and various other materials, well it was in 1986. Its the chloride that would attack the aluminum and maybe cause some discoloration, given enough time. I'm not sure how long, maybe a couple of years. Even then I don't think it would cause parts to literally disappear.When processors would sometimes leave aluminum parts in the acid to long when etching for anodizing, like over night. they would sometimes look like a crinkle finish. Once a plater lost a rather expensive aluminum part I had made, he said he didn't, but about a month later his driver brought over what looked like a piece of charcoal resembling my part along with a letter of apology and a credit for future work which was 3x his original invoice. Now that was sulphuric acid! It still didn't disappear! My background was machine shop. I know a little about materials solvents , cutting fluids rct and what will or wont ruin a part. I am absolutely certain no aluminum parts would disappear in a hot tank. If the sulphuric acid didn't make it disappear in over a month. I'd stake my life tri-clor wouldn't either. aside from that I don't think the crock pot would hurt the engine, afterall you all do it all the time. I'm just against putting ferrous materials in water they will corrode or rust. That's my only objection. The carburetor cleaner is probably the best bet. I use Coleman camping fluid, its "white gas" or was. Its great for degreasing like on oil soaked balsa or motormounts. it'll suck that Castor right out and the glue will stick again. Do the same to that varnish. It may need a little help from the acid brush.I've never had an engine get in that condition. Some of mine ran for years in the same airplane. Jim

Jim,

I'm not chemist either, but I know there are some alkalies used in hot tank solvents that are far more aggressive then acids on aluminum castings. Its also dependent to a fairly large degree on the alloy itself, some are highly resistant to dissolution others are not.

Brett Buck · « **Reply #19 on:** April 07, 2011, 01:31:04 PM »

Quote from: jim ivey on April 07, 2011, 01:01:04 AM

Well ty, better tell Brett ro run over to 182 and tell em "quick get that hot tank outta here it's eatin up all those expensive missle parts "

  That might be a somewhat more controlled process than your typical garage dip tank...

   I have done it (and my first job was working at a Gravely tractor shop, where we would dip the aluminum carb bodies all day long - 15 minutes at a time), but the crock pot/anti-freeze works so darn well with almost no chance of hurting anything that I think the dip tank is superceded. I *do* know that at least some of them *do* hurt cast aluminum - we forgot one in there once, left it overnight, and while it wasn't completely dissolved, it was certainly ruined.

   Brett

p.s. bear in mind that if you get your good old broken-in Fox nice and shiny, back to bare metal, you might find you don't have any compression left - because the varnish had become part of the cylinder/piston fit, and now it's gone. That can certainly happen when synthetic oil cleans the varnish and any sort of cleaning like this is far more effective.

Jim Thomerson · « **Reply #20 on:** April 08, 2011, 12:03:50 PM »

I am a heretic. For about three years, I have been running my Fox stunt 35 bought in 1977, and flown a lot back in the day, on Sig Champion 10% nitro, 20% oil, half synthetic and half castor. The engine has excellent compression, starts well and runs reliable. It has some crud on it, but it is from years gone by. It works to suit me. I have put one lean run on the engine; it heated up and died in the air. No damage or change in characteristics as far as I can tell.

jim ivey · « **Reply #21 on:** April 08, 2011, 01:36:39 PM »

Its the rust brett , thats what i meant about corrosion caused by water and you know rust is very abrasive. Henry & JC ran jewelers rouge thru thier engines with a machine that rotated the shaft without a plug. It was to free them up at the factory.I never saw a shiney (ball burnished) fox case, back cover, or head. duke didn't do that. Ball burnishing is a cheap process. In the old days pobably less than .01 of a cent each. The aluminum parts were thrown in a big ol barrel<---- called a speedee-burr (a tumble de-burring machine) along with some saw dust and some odd shaped steel media. (Kinda the shape of "caste- master" fishing lures, but smaller app. 3/8ths x 1/4 in.) They would roll em around about half a day. It would de-flash them and beat down all the sharp corners. Those who are really familiar with machine shop practices know how this was done! Brett if 4 D plating is still in buisness in RC , SV. strip your engine to the bare case and ask them to throw it in with their next ball burnishing job. you may have leave it a while maybe a week or so. BUT, when you get it back, it will be shiney like a knb or our engine. I was always tempted to color anodize a case and/or a head for the heck of it.

@jim

Balsa Butcher · « **Reply #22 on:** April 08, 2011, 05:14:07 PM »

One quart and already SEEMS gummed up? The key word here is "seems". It seems, but it ain't. Maybe when cold it doesn't "Pop" when you flip the prop, that's OK, it'll get back to that once fuel and spark are applied. If it starts appearing a little brown on the outside, that's OK also, it's a Fox, means it's just starting to get broken in.

jim ivey · « **Reply #23 on:** April 08, 2011, 09:03:14 PM »

Here ya go. hey its water sol. dont use it. this what was probably in your tank

Hot Tank Cleaners for Steel, Aluminum, and Soft Metals

Water-based, alkaline, and safe to use on steel and cast iron surfaces.

Removes paint, rust, burned-on foot soil, engine soils, and acid pickling residue.

Available in an oil separation cleaner and boffed for aluminum and food processing.

ALKATERG

High alkaline hot tank stripper that is safe to use only on steel, stainless steel, or cast iron surfaces. Removes paint, rust, burned on food soil, burned on engine soils, acid pickling residues, and many other resistant soils. Used for cast iron and steel engine block and parts cleaning, food processing utensils, industrial parts, and other similar applications.