new

[trowel]

hello, new here,
i joined this forum because im thinking of building a lawnmower racer and figured a go kart/mini bike forum would be a good place to start due to the uniqueness of the engine i have chosen to be my next victim,
im thinking of using a military surplus twin cylinder air cooled gas engine of around 8 to 10 hp, model no. 2a016,
as far as i know i will be the first to ''hop-up'' this particular engine but if anyone has done this before i look forward to your posts and help, i can buy 2 modified heads for this engine and is looking for a ''mild'' up-grade to start, it has been a while since i have built a racing or pulling engine so i am crazy enugh to try this, the other question i have is about the carb. this engine comes with a finicky carb. i don't care much for unless i can modify it, i would much prefer to replace it with 2 small dependable carb.s or a large bore single or double barrel carb., the engine is 16 cub. inch total, 8 cub. inch per. cylinder and has the splash type of oil dipper for the crank and rods, i would like to keep that seeing as this will be a mildly built engine and is looking for a 8 to 1 compression to start off with,
i can provide picture and more information on this particular engine if needed, thank you for taking the time to read this and is looking forwards to all and any responces,
trowel

 

[Doc Sprocket]

Sounds pretty interesting. There's not a lot of mower action on here, but hey- anything goes. We're pretty receptive to anything with wheels.

And yes- pics would be great! Welcome to the forum.

 

[Russ2251]

Everything I have read on this engine indicates 3hp ?
Is this correct? Seems low for a 2 cylinder, 16 cu.in. engine.
I imagine it is a torque monster.
http://www.clcc.org/images/TM_9-2805-257-14.pdf

 

[trowel]

2a016 engine

cool !, then i came to the right place,
i do not have a spare engine yet, both of my 2a016-111 engines are being used, but one will be coming along soon, building this engine is compleatly new to me compared to most others so im going slow and figuring out everything from the crank to the valves, a friend just e-mailed me about the inherent weakness of the splash type oil dipper and has seen many of these engines in the scrap yard due to throwing rods because of no locks on the rod cap bolts, they tend to come loose, if anyone has any advise on this please post,
the 2a016 engine is under rated by the military at 3 hp, these engines are more closer to 8 hp. and over depending on slight mod.s done to the carb., with the twin pistons they are hard to stall compared to a single cylinder and is built like a tank,
i have one on a ariens snowblower curently being used as a mower, the other 2a016 engine is on my ariens roto tiller, here are some pic.s of them,
trowel

 

[trowel]

test

oh, and the picture i just posted are old ones when i was testing both engine prefomances, i can provide current picture of both if any one is inerested,
trowel

 

[Russ2251]

...no locks on the rod cap bolts, they tend to come loose, if anyone has any advise...

Loctite #271, and be sure to torque to spec.

 

[trowel]

thanks russ,
would any one have any advise on carb.s (hopefully 2) for this engine, or is this so far out there i would have to experiment with different ones, i could use 2 MT52A tilliston carb.s but would much prefer something more modern and powerfull,

 

[bighead]

I have a few carbs.

ATC250es carb.
Two ATC110 carbs (They do not idle)
1980 Yamaha GT80 carb.

All are slide carbs. Not sure if you can use them. But if you can I will make you a sweet dirt cheap deal.

 

[trowel]

carb.s

thank you,
i know very little about slide type of carb.s but i looked up those carb.s on the net anyways and they would not work,
trowel

 

[the-cyborg]

I just installed a Mikuni Flat Slide 34 mm on a Subaru EH41 13.5hp single cylinder
you could possibly manifold a single large carb like that, or perhaps go with dual 24 or 28mm
I ordered a complete kit from NR Racing http://www.nr-racing.com/390raceparts.htm basically they are high performance motorcycle carbs adapted for industrial engine usage.

 

[trowel]

oh, hey, nice, i did not know mikuni made carb.s smaller then 28 mm, that what i use to put on kohler k-240 pulling engines, minuki carb.s are good carb.s, i have never heard them being called ''slide'' carb.s, is this a new model,
trowel

 

[the-cyborg]

I don't know if they are new models or not but apparently they do make them down to at least 22mm.
And yes they are great carbs IMO they are a better choice for what we are using these industrial engines for than the stock type carbs. they a allot more rugged and durable, you can mod them to no end, and best of all you can walk in to almost any local motorcycle shop and get replacement parts, rebuild kits and jets to mod them to your particular requirements.

 

[trowel]

thats great, looks like i may have found what im looking for, i tire of looking for carb. kits for junk carb.s thats no longer being made,
trowel

 

[the-cyborg]

thats great, looks like i may have found what im looking for, i tire of looking for carb. kits for junk carb.s thats no longer being made,
trowel

You may have to do some creative fabrication on intake manifold, and trying different jets until you get it to your liking, but IMO it worth it in the long run.

 

[trowel]

intake manifold is not that hard to make, i'v made adapters and intake manifolds for a range of different carb.s for kohler, tecumseh, clinton, briggs and wisconsin air cooled engines,
it is matching the right jets for this engine that's hard, more or less, i will be coming at this engine as 2 separate 6 hp engines, and working up from there, synchronizing the two cylinders with 2 open pipes is a big advantage, but keeping in mind that it is more or less a down-sized airplane engine covered in cooling tin work with a splash oil dipper rod,
trowel

 

[the-cyborg]

intake manifold is not that hard to make, i'v made adapters and intake manifolds for a range of different carb.s for kohler, tecumseh, clinton, briggs and wisconsin air cooled engines,
it is matching the right jets for this engine that's hard, more or less, i will be coming at this engine as 2 separate 6 hp engines, and working up from there, synchronizing the two cylinders with 2 open pipes is a big advantage, but keeping in mind that it is more or less a down-sized airplane engine covered in cooling tin work with a splash oil dipper rod,
trowel

In that case I would say a single 34mm would serve you well, or if you wanted to go duals I'd do twin 22mm but keep in mind now you have to synchronize both carbs just as you would have to on a bike with multiple carbs.
even at that I don't think it would be much of an advantage over a single 34mm and for the simplicity of a single IMO would be the best option at least that's the direction I would go in.
I've seen guys running 33mm/34mm on everything from 10hp to 16hp so a theoretical 10-12 hp twin shouldn't have any problems.

 

[trowel]

i know, im one of those guys,
i have not even built the engine yet and a few of the guys are already wanting to buy it to put it on their son's go kart or their jr. pulling tractors, (sigh), i have not done duels in a while, this should be cool,
trowel