K&B .35 Stallion Acquisition

Ken, thanks for your historic information and practical experiences on this engine. I don't know if the condition is original or not. Pulled engine apart as far as I could go. It has a nylon Crank Throw Spacer similar to the McCoy Red Heads. The prop shaft, a threaded stud is removable. Backplate has some wear on it, but it is light.

The prop nut, washer and shaft appear to be new and rust free and hardly any wrench marks. These may be new parts. The engine has been run, top of piston is coated with Castor varnish. Back then, they did test run some engines. I don't know if this is that or the engine was run by owner. It has no sign of mounting except for right back hole, but mark is not worn in like a tightened down screw with washer under the head.

I got it now soaking in heated antifreeze, will see in a day whether I can remove the cylinder liner. If I can do that, I can remove the piston and crankshaft. Then where rust appears, I can remove and polish it off. At one time about two years ago, someone was selling gaskets for this engine. Today, none appear on E-Bay except for the .35 Torpedo backplate gasket (Mecoa, appears their listing may have an error in it. Torpedo's didn't have a front nose gasket like the Enyas. Compared with my .35 Torpedo, appears uses the same gasket.) Mine though appears to be in reasonably good condition. I'll have to manufacture a head gasket.

George, I might have some Torpedo base gaskets. If I locate them ( I do believe I know where I stored them) your more than welcome to them. I received a box of engines from a former speed flyer. Every engine  was either broken or worn out. There were some rather nice engines in this box and sadly all items were ruined by either massive grinding or just abuse. It really pains me to see that. Several envelopes of gaskets and what I thought to be red head Mccoy gaskets turned out to be K&B items. My Stallions (2) are all intact and running well one is in a bag.

George, I also went back and took a closer look at your pics. Wow, that has some issues all right. While it may not look so good, I think it will be ok once cleaned. The pitting is pretty intense. I honestly have never seen that to that degree before. While I've come across some actually casting porosity issues, whatever happened to that engine is pretty serious. I think your on the right track though and it should be running in no time. Ken

Thanks Ken for offering your gaskets. I've already left a message for Shelley Ramos, E-Bay verysassyblond to see if she has them. She usually offers a complete gasket kit including nylon crank throw spacer. However, if she doesn't have, I may contact you, if I do I'll want to reimburse you rightly for them including postage, many thanks.

After soaking in hot antifreeze, this morning I took my Leatherman knife blade and by gently tapping on the crack between aluminum crankcase and steel cylinder all along its perimeter, worked the cylinder loose. Then with gentle prying and further tapping with a putty knife, I edged the cylinder until it fell out.




There is surface rust on the cylinder port and mating surface area. I was able to scrape most of the surface rust from the cylinder inside top that forms the combustion area at TDC. Darkening of the piston top is surface rust. There is rust on the back side of the crankshaft opposite the intake hole. Most of the rust was removed when the crank was turned.

I scraped away the gasket on the steel cylinder, both bottom and top. They appear to be the old graphite paper ones, similar to the car head gaskets of the early 1970's. Then I put the separated parts back into the antifreeze for further soaking before final clean up and polishing.

An interesting fact with this engine is that it has a steel piston pin full length without any pads. Connecting rod is unbushed solid aluminum. Running this engine with a slug of healthy Castor in the fuel is a must. Crankcase has a crankshaft bronze bushing.

This appears to be a low time engine that was probably only bench run at the factory. Was it worth my $30 shipping included for the engine? At this point I think so. Rarely does one get a low time engine at this cost. Most seem well used, although they may have some life in them.
It was a gamble I took and looks like I may have a good runner in short time.  

George, I really radius the ends of the wrist pins and polish them back. That's the real killer of engines with this construction. Once they start cutting grooves in the liner, it's game over. Even the Mccoy redheads with the brass end pads cut terrible grooves in the liner.

Ken Cook wrote:George, I really radius the ends of the wrist pins and polish them back. That's the real killer of engines with this construction. Once they start cutting grooves in the liner, it's game over. Even the Mccoy redheads with the brass end pads cut terrible grooves in the liner.

Thanks for the tip, Ken, I'll make sure I radius pin ends so I can get a reasonable life expectancy out of this engine.

One of the posters on RC Universe clarified that the Stallion production engines were not test run by the factory. This one has some rotational wear on the backplate from the nylon crank throw spacer inserted into the end of the crank con rod pin, so it was definitely run by someone. The crank throw spacer end, its button head is worn a little thin, which leads me to believe that someone may have used an electric starter on it.

Personally, I would never electric start this engine nor any of these traditional CL stunt engines, so I wouldn't prematurely wear out and fail the crank throw spacer. As soon as engine starts, the forward pull of the prop relieves any pressure on the crank throw spacer.

Anyway, tomorrow plan to remove the engine from antifreeze, do further clean up, polishing, etc. and start reassembling the engine for test run.

Hi GG, Nice overhaul project your doing on that K&B Stallion. I'm new here and learning stuff already. Didn't know about soaking in heated Antifreeze. Does it pretty much dissolve the fuel residue (caster oil I guess)?

I might actually have a Stallion in my rented storage unit. I'm going to head over there soon and check. I think it was on a Ringmaster.

Jeff

FlipStart wrote:Hi GG, Nice overhaul project your doing on that K&B Stallion. I'm new here and learning stuff already. Didn't know about soaking in heated Antifreeze. Does it pretty much dissolve the fuel residue (caster oil I guess)?

I might actually have a Stallion in my rented storage unit. I'm going to head over there soon and check. I think it was on a Ringmaster.

Jeff

Jeff.
Rather than "soaking in heated Antifreeze", simmering the parts in the antifreeze for a reasonable period of time is the way to go. Because of toxicity concerns be very careful with exposure to fumes. Most people successfully use a slow cooker or crock pot for this job. Not having that appliance myself, I have successfully used a small toaster oven with the engine submerged in a small heat-proof tub. Ceramic would be best. Use the antifreeze "neat", as in, not diluted with water as you would when used in a car engine. I crank the temperature up to about 120-130 degrees Celsius and leave it overnight. (Just on the verge of boiling). I have had mixed results. Some engines come out like new, some emerge with little difference, although generally most of the gunge is gone, just that the finish of the alloy parts is variable.
Again, be very careful handling this stuff.

Rod.

[quote="GallopingGhostler"]---One of the posters on RC Universe clarified that the Stallion production engines were not test run by the factory.

As I recall, a Stallion .35 retailed for $9.95 in a 1971 hobby shop, so a factory test run was definitely out of the question other than perhaps one out of a thousand.

Back in the days of real brick and mortar independent toy/hobby/craft shops, a distributor would pay K&B roughly $4.50 for the $9.95 Stallion and sell it to a retailer for $6.00. If retailer was a good solid account for the distributor and paid his invoices in 10 days or less he could take an extra 5 + 2 percent discount and get free freight from the distributor. This was when the federal minimum wage went to $1.70/hour in February 1971.

Thanks, ticomareado for the engine's historical business side info.

roddie wrote:Enter "my dad"............ who proceeds to start the engine on the first-flip. George..... an open-face Stallion .35 being run "indoors" is really loud........   My dad was my hero that night.

Thanks for the story, Roddie. Loud Pipes Save Lives!

"Thanks, ticomareado for the engine's historical business side info."

You're welcome. Now you do the math on a $3.98 Baby Bee run through the same distribution channel.

Oldenginerod wrote:

FlipStart wrote:Hi GG, Nice overhaul project your doing on that K&B Stallion. I'm new here and learning stuff already. Didn't know about soaking in heated Antifreeze. Does it pretty much dissolve the fuel residue (caster oil I guess)?

I might actually have a Stallion in my rented storage unit. I'm going to head over there soon and check. I think it was on a Ringmaster.

Jeff

Jeff.
Rather than "soaking in heated Antifreeze", simmering the parts in the antifreeze for a reasonable period of time is the way to go.  Because of toxicity concerns be very careful with exposure to fumes.  Most people successfully use a slow cooker or crock pot for this job.  Not having that appliance myself, I have successfully used a small toaster oven with the engine submerged in a small heat-proof tub.  Ceramic would be best.  Use the antifreeze "neat", as in, not diluted with water as you would when used in a car engine.  I crank the temperature up to about 120-130 degrees Celsius and leave it overnight.  (Just on the verge of boiling).  I have had mixed results.  Some engines come out like new, some emerge with little difference, although generally most of the gunge is gone, just that the finish of the alloy parts is variable.
Again, be very careful handling this stuff.

Rod.

Rod,
Thanks for the information on how to do the antifreeze clean. I'll be very careful if I try it. I don't have a slow cooker either.
I thought I might have had a Stallion .35 in my storage unit but went over there yesterday and didn't see it.
I think it went with the plane in a trade or something.

Jeff

You are welcome, FlipStart.

Rod, your methodology uses higher heat than boiling, which I haven't tried. My coffee percolator similar to a crock pot on low heats a touch below boiling point. The percolator does just as good of a job as a crock pot plus it doesn't require as large a quantity of antifreeze. I can clean an engine or two, and do the next with clean antifreeze. Whether better or not? That I can't say, but so far my methodology has worked for me on a half dozen engines. The heat sufficiently softened the congealed Castor oil so I could separate the stuck cylinder from the crankcase with a little gentle persuation.

I did things a little different in that I added a small quantity of water since I was running low. Now, the engine is darkened similar to a few engines with dark aluminum finish, like the Sanye AP .09, some Enyas and MDS engines. I removed the items, started scrubbing with dish soap and a green Scotchbrite pad. The outside of the cylinder that sits inside the crankcase has heavy rust, similar to the inside top where the piston at TDC sat for a long time. It is not enough to severely weaken the steel or severely pit it, but it is there. This piston shows some rust outlined where it was exposed to the exhaust port. I got most of it off with the green pad, will later use fine steel wool to remove the remainder on both the steel cylinder and iron piston.

The head gasket is well stuck to the aluminum head, wonder if the owner used some form of gasket shellac. Will need to do further work. I did a test case of applying and rubbing with a paper towel Mothers Mag and Aluminum polish on one side of the bottom of the crankcase. The brighter aluminum is coming back, with a mild aluminum gloss it looks like a die cast factory finish. I'll be able to restore the crankcase, back and head to natural aluminum color and get rid of the odd sand blasted finish with some elbow grease.

With it soaking and cleaning the aluminum exterior pores in the so called casting occlusions has made me see more clearly that this engine was subject to a damp environment. For all I know, it may have been a field find near an old model flying field. The head and crankcase on the intake bypass, left side of the engine have similar continuous corrosion pattern from crankcase to head. Parts are cast separately, so if there were casting occlusion imperfections they would not look uniform between pieces.

It is now more clear that at one time, it was in fact mounted to an aircraft. The diameter outline of 4-40 lock washers show on at least 2 locations, one on each side. The sand blasting must have removed enough that the other two holes look as though they were untouched.

It is late, so the parts are now on a paper towel to air dry. Tomorrow I'll be able to continue my work.
The bride of Frankenstein will live again.

The slightly diluted antifreeze discolored the engine aluminum exterior parts a uniform darker color. In real life they look better than in the photos. After the soak, the so called occlusions, which are surface corrosion is more evident.






Here's how the surface polished with Mothers Mag and Aluminum Polish looks like. I'm almost tempted to put the crankcase back in the antifreeze and let it re-discolor.  


The crankshaft shows signs of rust in various places, but this is cosmetic. It will run fine as-is.

I wonder which parts are common to a/or are interchangeable with a Green Head Torpedo .35 stunt engine. (retailed for about $15 by late sixties if memory serves me and looked the same externally except for green paint on head and crankcase artwork)

ticomareado wrote:I wonder which parts are common to a/or are interchangeable with a Green Head Torpedo .35 stunt engine. (retailed for about $15 by late sixties if memory serves me and looked the same externally except for green paint on head and crankcase artwork)

I have a .35 Torpedo, later on I can check. There are already differences because of the left exhaust port for the Torpedo and right exhaust port for the Stallion. Because of this difference, the crankshafts are timed differently and thus can't be interchanged. Also, the prop thrust washer or prop drive adapter (K&B terminology) can't be interchanged, because the Torpedo's crankshaft mount area is tapered whereas the Stallion is stepped and keyed with a flat spot. The Torpedo's steel one is more like a thick washer whereas the Stallion's is cast aluminum resembling current ones on most engines.

I think I read somewhere that a Sportster prop drive adapter can be substituted for the Stallion. I have a Sportster .20, so later I can check.

The cylinder has its share of rust, but where most rusted is not located in the piston travel area. I was able to remove the gasket fragments and some rust from the top and bottom fins using a utility knife with sharp box cutter blade. My suspicion of gasket shellac was wrong, the "glue" is simply impregnated rust and the affinity of the ancient gasket material for the machined metallic surfaces.






You can see from these photos where the engine piston rested at top dead center during much of its "abandoned and unloved" life. Evidence of surface rust outlines the cylinder bypass port on one side and the higher exhaust port on the other side. Both top and underside of piston has surface rust, but this is cosmetic.




The head shows evidence of rust in the mount screw holes.


Now that I have had a chance to further forensically examine this engine, the circumstantial evidence reveals that the seller's story of occlusion imperfection occuring during the manufacturing casting process was stretching the truth a bit.
All is not lost, though. Franken-girl will live again!

It's going to need lots of TLC & plenty of elbow grease but I can see it's in the right hands.

It reminds me of my dad's Johnson engines a little. He had a .29 & .32 IIRC.

Jeff

FlipStart wrote:It's going to need lots of TLC & plenty of elbow grease but I can see it's in the right hands. It reminds me of my dad's Johnson engines a little. He had a .29 & .32 IIRC.

Thanks, Jeff, you're right, it will require some work, but being retired, I have more time on my hands versus when I was in the working world. Most of the rust is not in critical areas. Some in the photos like of the piston, in the pin area is flash rust from simply exposing to water wash after removal from the antifreeze. I have new stainless steel Allen socket head screws in the right size that I will use to replace all the factory screws.

I'm almost tempted to paint the head the same color as the Green Heads. It won't be historical, but it will look nice. The other option is to paint it red the same as the Red Head McCoys.

Regarding the Johnson engines, I've seen them on E-Bay, but just haven't had a hankering to get one. From what I've heard they were good runners. But if I do that, then I'll be tempted to get a working order 5 tube (valve) AM table radio with Deco Bakelite plastic case to go along with it. I still remember my father's 5 octal tube socket Sears Silvertone AM radio in ivory plastic and brown speaker grill cloth from the 1950's. In the kitchen, he used to listen to it a lot up to the late 1960's until it was replaced.

Today, I did further cleaning up of the engine parts using fine steel wool. This removed the sand blasted finish from the aluminum parts, imputing a fine brushed metal finish to the aluminum. I could stop here, or I could further remove the brushed look to polished with Mothers Mag & Aluminum Polish. The steel wool also removed the rust residue from the steel parts, cleaning them up considerable. Now, with the majority of the rust removed, once reassembled, oil will take care of the rest to prevent further rusting. I think you will see that the parts cleaned up quite well.
























Last photo of the piston, you'll see a steel wool "hair" strand. I will blow all engine parts with compressed air prior to assembly.

The engine may look worse for wear from the photos. Actually it isn't as bad as it looks. The photos are up close, magnifying flaws. To the naked eye the engine looks much better.

The crankcase roughness does reveal the extent of the effects of weather upon the metal finish. This engine may have sat for a while, up to 2 or 3 decades in a midwestern field. If the engine could talk, I'm wondering what free flight or simple R/C aircraft (1 or 2 channel without throttle) it might say it belonged to. In the mid 1960's multi-channel was very expensive, akin to costs associated with flying turbine jet aircraft. Many who gave RC a try would settle for 1 or possibly 2 channels, escapements would be the least expensive. May be it was on a Goldberg Senior Falcon flown without throttle control?

We don't know at this point, but as you see from the photos, it was definitely not manufacturing defects but rather corrosion that played a major part in marring the exterior finish.

And, after closely looking at the piston pin, the ends are radiused and polished. Without any serial numbers, I can't tell whether this was an earlier or later Stallion. Also I learned from Peter Chinn's engine tests (see Sceptre Flight) that if one removes the plastic venturi insert, suction is still strong enough that the HP gain will be close to the engines it competed against, the Foxes and Testor McCoy Red Heads.

With the plastic venturi insert in place, it should be a fine engine for .35 CL aircraft toward the lower end of wing area, such as the Sterling Kit S-1 Ringmaster. The extra suction should prove it to be a very bullet proof engine for that aircraft.

I don't have any personal experience with rock tumblers, but have read about them being used on these kind of hard core restoration cases. That may be worth exploring. (Just make sure you don's polish out the crankcase bronze bushing.) This Shelley chick out in Califas who does all the McCoy rebuilds was a video of the "heat and beat the piston" technique (I hope that wording came out right.) for compression restoration on McCoys. If that technique is usable on the Stallion, my prediction is that yours would benefit from it if you are looking to have a runner at end of project.

Is this your engine bottom right? Price is low but shipping not. The marine engine with flywheel is interesting.
Maybe for parts.

https://www.ebay.com/itm/Lot-of-6-R-C-Model-Airplane-Gas-Nitro-Engines-Assorted-Brands-and-Sizes/302876271775?_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D1%26asc%3D20131003132420%26meid%3D2a0393a9bfd94c1dbb26635383e81997%26pid%3D100005%26rk%3D5%26rkt%3D12%26sd%3D142930842469%26itm%3D302876271775&_trksid=p2047675.c100005.m1851

ticomareado wrote:I don't have any personal experience with rock tumblers, but have read about them being used on these kind of hard core restoration cases. That may be worth exploring. (Just make sure you don's polish out the crankcase bronze bushing.)

If I were polishing rocks, a tumbler may come in handy. This, the exterior finish is already marred. I can make it look better by polishing the aluminum, but it is what it is. Besides, once in an aircraft, one will hardly notice it. It will look good and perform well enough to be something other than a love child.

This Shelley chick out in Califas who does all the McCoy rebuilds was a video of  the "heat and beat the piston" technique (I hope that wording came out right.) for compression restoration on McCoys. If that technique is usable on the Stallion, my prediction is that yours would benefit from it if you are looking to have a runner at end of project.

It works on the McCoys because the piston is domed. Carefully tapping the domed top with a hammer and punch will cause the piston perimeter to expand a little, allowing it to be relapped with the existing cylinder to restore compression. You can't do that with this K&B piston because it is flat topped with a small fillet section to support the piston baffle on its top.

I believe this engine will have sufficient compression once assembled. It is a low time engine from what I can see. It had compression before I started working on it, and I didn't do anything to remove metal to reduce that compression. The cylinder portion rusted was above the piston, which sat at TDC. The piston skirt sealed the exhaust port and the crankshaft sealed the venturi opening. So, relatively speaking, there was not much rust in the interior air space. There was rust on the cylinder exterior and bottom fin area, and cylinder top fin area. Most likely, both paper gaskets acted like a wick to permit moisture to permeate these areas.

crankbndr wrote:Is this your engine bottom right? Price is low but shipping not. The marine engine with flywheel is interesting. Maybe for parts.
E-Bay #302876271775: 6 RC Model Airplane Engines Assorted Brands and Sizes

Yup, that it is. If one doesn't have a business account with one of the shippers, $15 for 6 engines is about what one would pay for postal shipping, IMO. Plus, those engines especially the .60 is somewhat heavy. It's a nice lot, but not enough for me to bite. I've got enough engines as it is, just need to put them to useful work.