Neat little modded CS .061

That looks like the early head wrench style, they later changed it to two flats. The boxes also changes, and they were marketed as Brodak MkI engines at one time too.

These engines came as .049 (blue head) and .061 (read head), and also as RC engines.
I have a few of the .061 RC ones, and they suffer a bit from the "lack of quality control" syndrome. There were quite a few threads on them on RCU at the time. Here is one thread that I started; CS .061, I give up...

After sealing up the crankcase with some JB weld (it was leaking through casting pores) it actually ran quite decently in the end, and would do around 18000rpm on the APC 5,7x3 prop, or around 17000rpm on a Graupner 6x3 prop. So about .049 power in a .061 disguise...  

I'm going to have to check out that thread. With a MAS 6x3 and Sig Champion 25% this on topped out at a steady 12,500 RPM with a steady idle of 4500. The transition was instant. However, there was a timing shim under the piston liner that I damaged. And, the liner never stayed where I wanted it. So, I think it was probably several degrees off in each of the two directions. Regardless, I am happy with how well it ran and how well it idled and transitioned from idle to WOT. I don't know tat it is really worth a whole lot of playing around with as long as it runs this well now.

The CS .061 was also  offered in a ABC version and it runs quite well. The one I was running had the head like Bob's but it wasn't anodized red.I also have a .07 which is also ABC and a mill finished head. My Brodak .061 was a iron piston steel sleeve which was extremely mild comparable to a Cox Babe Bee. It woke up a bit when I got rid of the standard plug and instructions claiming to use 10% fuel. I drilled out the threads to fit a Glo Bee plug. I used the head as a clamp and poured the vitamin N ( Sig 35%)  to it . This yielded a considerable amount of rpm's and starting reliability.

Bob, the Brodak was supposed to have a roll pin holding the liner, it didn't. I suppose that cost too much. The same problem occurred when you tightened the head in that the liner would turn

http://www.ebay.com/itm/CS-061-ENGINES-AND-PARTS-/232321478307?hash=item3617706ea3:g:G4IAAOSwlndZCTeO

bid ends in about 3 hours.. many CS engine parts. Only 3 bidders thus far $102.50 thus far.

That's a whole different animal there.

Yes very true lol... I have the sport CL and RC versions and the speed CL and RC versions.
This one is a great buy for CL use sport or speed just how you prop it.. 2hrs 18 mins left.
I am not bidding but thought someone might be interested.

If I stick with this I will probably just cut a few cylinder shims and switch to an APC 5.7x3 prop. If it shows some good potential then the indexing roll pin might happen. Right now, I was just looking for something to power the slower, gentle flying planes like a Q-tee or an Eindecker with a good throttle.. I have several throttled Norvels to provide the faster planes with a little extra zip.

Something that really surprised me was that when I kept the engine in the garage the cylinder almost fell out. When the engine was in the sun (S W Fla, almost 90 degrees) I had to work the liner out and tap it back in. I also had to tap the prop nut because it wasn't tapped far enough to tighten down tight enough to secure the prop. This is really odd since I had run the engine once before. I do have one of the blue head Brodak .049's and the current Brodak .049. They are both good runners that don't put out too much power.

This looked like an ABC engine. How do I tell? Thanks for the glow plug idea, Ken. I may look at some clamp type plugs and see what might work. That would probably be the cheapest and easiest way to boost its output. I think I paid thirty dollars or somewhere in that range for this engine. So, I am willing to do some drilling and what not on it.

Kris,

I read your RCU post. It gives me some hope. I don't know that the engine is really wortht the effort, but so what. Maybe I will give it a much more thorough look and see if I find any holes or leaks. Your numbers are much better than mine and I fine hope in that. I think my low and mid range is probably better because I have a Cox carb and have adjusted the air bleed. I will have to see when I get some more free time. At least I have a little hope.

Bob, remove the head. Typically the liner is chromed and it's not chromed where the head gasket meets the cylinder head therefore this areas is usually brass in color.This piston would also be aluminum vs iron and should reveal a bright aluminum patina. Generally iron pistons discolor due to heat. Of course if you take a magnet to any of the parts in there it shouldn't stick to any of the pieces. Henry Nelson at one time was making a cylinder head for the CS engine that received a Nelson plug. The head alone was more money than what you paid for the engine but it was a offering. Ken

The engine originally talked about here is definitely iron/steel construction. It was their sports engine line which had nothing in common with the competition models (GZ) that the later pictures shows. The GZ were ABC and highly competitive, if you get a good one and now how to fix it...

The Nelson heads for the GZ engines are a bit different, they actually expand the head against the cylinder, so don't try to remove the head without untightening the Nelson plug first...

The GZ came timed for an open exhaust (N) or a tuned pipe. I have one of the "N" version and it will spin an APC 5.7x3 at around 20600rpm without breaking a sweat...

Here is a picture with a G-mark carb;

Kris, Henry made a Nelson head for the Brodak versions. I was reluctant to buy one. I flew against Henry last year in which I wanted to ask about this again. Henry sold his machine shop but he still has some equipment to play with. I've always wanted to play with the Brodak version a bit more and I don't know why. I suppose the engine appears to have good potential. My engine wouldn't run initially due to a large piece of flash in the venturi opening under the spraybar . I finally got the engine to work but my results yielded the same results as yours in terms of .049 offering. Ken

Ah, I din't know that he made one for the Brodak version too.

I bought an extra head for mine and drilled it out to act as a clamp ring for a Norvel insert, an idea presented by AndyW on RCU at the time. This surprisingly didn't change things much, but perhaps I didn't give it enough head shims and the engine might have been over compressed.

My engines were all over the place in terms of deck height and stock timing. The strongest one had an uneven exhaust port which raised the timing and it seemed to rev a little better. It also need four head shims if I remember correctly. There is always something of a challenge in "Lemon" engine that is hard to resist. Perhaps I should give it another go...

The intake port can be improved on too, it is circular (like in a medallion engine) and a square one would be an improvement. Below are some of the mods that AndyW did to his engines;

HOLY CRAPOLI!!!!  I drilled out the head to accept a clamp on type of plug. WOW, what a difference. I used a hot Merlin type of plug, Sig 25% Champion and a MAS 6x3 along with two head gaskets. It was idling beautifully from 5,200-5,500 RPM and topping out between 16,900 and 17,100 RPM with a virtually instant transition from idle to WOT. I was surprised beyond description. Ken, the idea to switch to this type of plug paid off way more than I even thought possible, thank you for sharing that idea! I also have a Brodak .049 MK I and a Brodak .049 Mark II that are both good, docile runners that will end up getting this mod. WOW!

All the number from running were with the muffler installed.

Bob, I had good success with it as well. I was using it on a small 1/2A and I switched to APC props 5x3 and I was getting decent rpm's. I took an engine that really wasn't working for me and made it useable. Brodak has the CS parts on clearance. Heads are still available if you wanted to retain the 1/4-32 plugs. Call me crazy, but I liked the look of the engine. I have a CS .15 which I think is worth posting a picture of. It's a nicely made engine. I never ran it and it resides in a box. Did you ever confirm that your engine is a ABC?

It looks like an ABC. This weekend I will probably take it apart to install another cylinder liner shim and possibly some type of pin to keep the liner from rotating. I will use a magnet to see if it is ABC or iron. Visually, the piston and cylinder look like they are ABC.

I found a single sheet description of the engine neatly folded in the box. The hosting service doesn't like my scan so I can't post it. Any way, it says that this is a CSG061 which is an ABC engine. It also says to use as much as 40% nitro.

Glad to hear that it is running well!

I think that the G stands for Glow, while a D would stand for a diesel which they were also available as.

The early CS, like yours, might have been made in ABC and iron/steel, while the slightly later Brodak I version was only offered in iron/steel. It shouldn't be hard to tell the difference, a true ABC engine will only have a cromed bore only, and the outside is showing the brass.

Do post some pictures if you take it appart.

Nice looking engine fit90 , i have been reading here and that's a great improvement with the insert plug . Never had one of these engines but sounds like it will make a good subject for a fairly large sport plane and give a smooth transaction when throttling . Have you got a plane set for it ?

Hi Eric,

I was originally going to use this engine on a Champion Eindecker but now I am thinking it might be a little better suited to a Q-Tee. If I go with the Q-Tee I might put ailerons on it and have a four channel plane. I am saying this knowing that I currently have endless projects going on right now. But, I have always wanted a four channell Q-Tee. If I ever do go that route I will definitely post some pics.

Bob, here are two of the CS sport engines I own. The smaller mill is the CS .07. This engine is just slightly larger than the .061 case but not by much. The head is much larger. This is a ABC configuration and I'm pretty confident it will do well. I'm just not happy with the small exhaust opening in the liner and case. The other is the CS .15. This engine appears to be very high quality. In fact, I find it to be on par with OS .15's. ABC construction which looks to be done very well and a super high mirror finish. The instructions that came in the box was for the CS .15 diesel. I'm looking forward to running this one.

hmm somehow I double posted

Hi Ken,

Those are both nice looking engines. The one with the red had looks really nice. I do love the red heads, though. I have been through this .061 and just went through and ran a Brodak .049 Mk I today. Everything looked good except that there was a lot of crap in the crankshaft of the .061. Any way, I modded them both to take a clamp on plug. Today I ran the .049 on Sig Champion 25%, a Hot Merlin plug and an APC 5.7x3. It topped out at 17,000 with the muffler and 17,500 without the muffler. The idle and transition was pretty poor, though. I think if I switch to a Cox carb and the heavier MAS 6x3 both the idle and transition will improve. I am hoping to get a chance to try this weekend.

I have heard so much bad about these engines. But, both these engines have proven to be great. Maybe I just got lucky.

If I switch carbs on the .049 I will post the results. Also, I am a little concerned about drilling the head for a Merlin plug on the .049 Mk II because I am not sure that three screws will hold the head down evenly without any possibilities of warping. There are spares readily available, though.