M12B reassembly with new main bearings, followed by a load test

We reassemble this little m12b engine with new main bearings. We look at a model to help understand the principles of engine timing, and we start the engine and put it to work on our generator.

[@SimWinBock]

I have one of these engines and found that putting Loctite on the pin that holds the rockers removed the slack in the rockers which allowed the valves to open further and provide better responsiveness and smoother running.

[@Jj-xf5og]

Excellent,excellent presentation. You have a gifted way about you Keep on keeping on brother

[@therandomman6647]

When working on something small, I recently learned that the camera focuses better if you zoom in rather than bring it to the camera.

[@blk77sunshn]

Great video! I really enjoyed it. Keep them coming !

[@williamburgess4732]

Great tutorial thank you.

[@jessekalahar417]

Enjoyed the video as always. Really cool seeing the helical gears for the camshaft. I thought that was pretty interesting.

[@Jj-xf5og]

Just an excellent excellent video covering several things. Excellent presentation and methodical way of telling a story. You would have been an excellent shop teacher back in the day.. too bad they did away with all that. Why is it we teach our kids almost nothing that is useful n fp

[@IWA-ke3pv]

Hello, thank you for a very technically competent and interesting video on your channel. These videos are very useful for those who are engaged in the construction of such engines. I also want to build a primitive, four-stroke motor. Please, if you have the desire and opportunity to report cam camber (degrees) on such small engines. I wish you good health and further creative success. Sincerely, Valery.

[@TestECull]

27:55 same as a standard glow plug. I almost wanna try that in my M17B as well, throw one of my OS 8s in it and run it off nitro fuel.

[@jonathanfry7550]

Great video, not sure if I'm crazy or if you noticed or not but you never mentioned that the engine does seem to be running A Lot Better now. 👍👍

[@TestECull]

21:04 this is how OS and OS clones do their cam timing in rc aircraft. Same exact gear arrangement. Only, the crank gear is machined directly into the crankshaft rather than being a seperate part.

[@steam212]

OS engines are VERY well built and do their intended purpose very well. These little engines are not intended to run at the RPM'S that an OS engine will do. In all honesty it's like comparing a Briggs and Stratton flat head 5 horse to a Kawasaki KX 250.

[@TestECull]

@@steam212 Oh believe me I know OS quite well. I've got plenty of RC cars and airplanes powered thusly. I would unironically say my OS FS70 Surpass and FS48 Surpass are more reliable than 95% of the things you find on a modern car lot! They certainly give me far less grief than my mom's '03 Explorer or my '14 Challenger do. Wasn't meant so much as a comparison as a nice little sidenote of commonality between the two. It would be nice if Microcosm would cut the helical teeth into the crank directly, though. Would potentially reduce the timing issues these engines often have right from the factory floor. I think a lot of the reason these Microcosm engines have such wildly variable timing that some run like an OS out of the box and others won't run at all OOB is because the cam and spark timing is dependent on a little setscrew holding certain parts in place which requires far more care in assembly than is practical for a chinese low-cost assembly line. A bit more G-Code on the crank machining step would result in a dramatic increase in customer satisfaction when the engines get 200% more consistent from new.

[@luiscoelho4151]

Ok the M12 B are 4 strokes question answered sorry again 😅

[@steam212]

I really like this little engine to be 100% honest with you. After the work I did to it I've done absolutely nothing but add fuel and be sure that the oil is topped off (changed it a few times) it has been a very dependable and good running little engine. I don't really work it with a load, just run it.

[@Red-Dog7]

Hey, I’m new to model engines. And greatly appreciate your videos showing off the components and how to diagnose issues and resolve them as well as disassembly and assembly. I was just curious on how long these engines can actually last, with proper maintenance and minor repair if needed. Can they last as long as a real engine, or do they have short lives in comparison?

[@steam212]

I really appreciate your comment and support 👍. To give you my honest opinion, they will last and run for many years with proper maintenance if they are not abused (over revving or over heating) but will they be able to run 8 hours a day for days on end I don't think so. I hope that makes sense. Thank you for watching and welcome to the hobby

[@IWA-ke3pv]

Hello, I ask you to provide the technical data of the camshaft of this engine. The main thing is that I am interested in the location of the camshaft cams - (camber). Sincerely, Valery.

[@TestECull]

0:54 that is a standard clutch bell bearing size for nitro RC cars. Why they're so ubiquitous.

[@davidlavergnelacasse2356]

Great video I wanted to know if the bearings last after changing them with those I wonder if bigger ones would do better I could enlarge the caps that hold them if needed I will soon have one to test them myself I am looking for feedback from this product or more Litle trick that could help improve this Litle engine and the time of use without damaging it, it already seems very well made despite the defective bearings and the lack of real piston ring which in my opinion greatly reduces the time of use as y want To use this in a boat i dont want To go swim 😅 like the conten on this channel and this vidéo was alredy god informations Thank

[@steam212]

Hi David, so far these bearings are doing well. I tend to think that the crankshaft isn't 100% true end to end in my opinion. I am trying to get ahold of of a cast iron ring manufacturer to see if they can make rings to fit a 1/2" bore (we'll size them to fit) and I have not gotten a response yet. I am uploading a short "monkeying in the shop" video now about modifying the exhaust. I also plan to make a custom intake manifold for "testing" purposes on the horizontal cousin to this one. Stick with us,. Thank you for your interest , question , and your desire to improve things.

[@davidlavergnelacasse2356]

@@steam212 It is precisely m12 b that I am going to have for tests I believe that the b is for boats maybe I have some idea for the rings maybe I can find someone for that the guy makes rings for old nitro k&b and other engines I will try to contact this guy In the worst case I will do it myself making rings is harder than making a simple piston but remains an interesting project I think it could be made of stainless steel maybe add one more ring with lubrication port under it and more upgrades like ad seal rocker cover wit tube on push rod ad seal behind flyweel at the cam gear cassing for oil new exaust mabe custom Intake I think I'm going to polish the crank and cam wear before use I've seen that some people have funny cam lobes a bit square i love To build engine wil look forward for new vidéo from u i like the steam To u have cool content

[@TestECull]

@@davidlavergnelacasse2356 B just means an alternate model, not that it's meant for boats.

[@TestECull]

@@steam212 If you've got a lathe you've got all the tooling you need to cut rings for it. They're not *that* hard to make. Plenty of information on the subject if you join/browse Home Model Engine Machinists forum. RMJ Machine Worx, who took over Bowman in 2017, makes rings for all sorts of stuff as well; I bought a ring from them for my old OS H-40P aircraft engine and it worked a treat! They should be able to cut rings if they have the right measurements.

[@davidlavergnelacasse2356]

@@TestECull Thank you for specifying I just thought it was a good way to design it as such because it is better adapted compared to the original model

[@joesenkalowski7912]

When you were tightening the rod end, what was the click, click? LOL.

[@steam212]

Torque spec. Lol

[@KrisDouglas]

Torque wrenches (used for tightening things to an accurate force) click when they reach the torque level you specify. It's a running joke to just do stuff up really tight and say click instead ;)

[@randytucker9158]

Where did you get the lamp? Did you build it?

[@steam212]

Hi Randy, I wish I could let everyone know where to buy one, but this is the only one I've run across. I bought it at a swap meet about 20 years ago. I can't find any maker's marks on it anywhere.

[@enedenedubedene4811]

Autofokus Failure😰😰😰😰😰 Viele Grüße aus Germany

[@steam212]

This dang GoPro is not the right choice for what im using it for, I should have bought a more suitable camera to begin with, but if I remember what its capable of I wont ask more out of it,