DJLaPalme

Are chain saw engines more powerfull than weedeaters? Where is a good source of Walbro carburetors? I have a McCulloch 46cc engine I want to use on an airboat if possible. Dennis

backwood666

yes chainsaws are more powerful with lots of tourqe

crispyspa

Not only do they seem to have more power, you don't have to use pusher props with them.

2manytoyz

Amazon carries that brand of carb. Don't know what size/model you need, but here's one example: [link]http://www.amazon.com/Lawn-Mower-Part-Carburetor-WYL-19-1/dp/B001OKBDAG[/link]

71dartswinger

i took apart a chainsaw that i have had since 1969 it is a craftsman 24" bar cant buy bar or any case parts and it needed a few parts
the only problem i see is the exhaust is the same side as clutch so i will end up trying to sell. it runs great was saving for mini bike but it is too small. dont know if it would work on air boar
will work as inboard in boat.

martno1fan

You dont have to use pusher props with any motor you can use either one ?.

DJLaPalme

Martno1fan, regular weedeater engines output shaft turns counter clockwise(ccw) necessitating a pusher prop(if the engine is in a pusher configuration). Chain saw engines on the other hand rotate clock wise(cw) which allows the use of tractor props giving airboaters a much greater selection of props. If a chain saw engine has higher torque than a weedeater does'nt that mean the stroke of the piston is longer? I better stop for now. All this thinking is giving me a headache. Dennis

crispyspa

"traditional" pusher airboat configuration using a chainsaw engine needs a tractor prop.
"traditional" pusher airboat configuration using a weedeater engie needs a pusher prop.

"puller" type airboat using a chainsaw engine needs a pusher prop.
"puller type airboat using a weedeater engine needs a tractor prop.

If you are putting the prop the flywheel side of the chainsaw on a "traditional" pusher airboat, you need a pusher prop.
and If youehlhd;ans;nf9408toyh;gf;oaga..........blablabla lbalblalblablalblablablblabbabblebabble .......
Yup...headache. LOL

I'm not sure about the stroke... I think they have more power because of larger cc's. Anybody know for sure?

DJLaPalme

There you go getting me all confused again. You said exactly what I meant Crispyspa. I believe most chain saw engines are bigger in cc's, but I've heard that cc for cc that they are stronger, but not sure just why(bigger carb, longer stroke, etc., etc.). Dennis

controlliner

The only bummer about the engine you chose is, it has reed valves and points. Piston ported engines are more reliable.

RS 38-40

My Feedback: (3)

I know back a few years before electronic ignition the engines with points used to do funny things to radios . We had to shield the plug wires and all sorts of stuff to try to make it work .

crispyspa

Even the pointless (magneto) ignitions do that. I think that the 2.4Ghz systems are immune though.

DJLaPalme

Good news! I checked my engine tonight and no reeds or points. This engine is looking better and better. Can anybody recommend an electronic ignition and where to purchase it? Dennis

controlliner

It is strange how the engine has no reeds, The carb is not mounted on the cylinder, it empties into the crank case. I have worked on a lot of chainsaw engines like this one and they had reeds. Mabe someone modified this one or something. Strange there is no points under the flywheel. Mabe someone installed an electronic ignition module.

DJLaPalme

The carburetor is mounted on a rubber mount that is bolted to the cylinder and go's directly into the intake port in the cylinder. There is nothing behind the flywheel except engine. There is a pickup coil over the flywheel(magneto?). I also have a Walbro WT334 carb on it which is supposed to be a pumper, but the pressure port in the intake manifold side is blocked off. There is a fitting on top of the carb which I believe is to run a pressure line from that fitting to a pressure tap(fitting) on the side of the crankcase below the carb. I will try to get pictures of it on here soon. Dennis

DJLaPalme

I turned my engine over to my local machinist(Lester Burch) for a prop hub to be made. When I get it back I will be installing an electronic ignition on it from Southeast RC Engines. That should make this engine perform even better. Can't wait to get this boat done and on the water. Dennis