78Honda hobbit new carburetor was installed successfully, then

After the new carburetor was installed successfully yesterday, everything was running great and smooth. This morning I was trying to get it running again. When I put the carburetor on the “choke” for the start, I heard a short burst sound beneath possibly from the engine. From that point, I could feel the crank shift is slow and heavy. And I can’t get it run no matter how hard I try. I wonder if my engine is blown? Hope not! Everything was running great yesterday :( Feeling defeated. Can anyone kindly share some advice or what should I do next? Thanks!

Re: 78Honda hobbit new carburetor was installed successfully, then

Update: when I paddled, the engine makes low roaring sound... Light is on. But the moment I release the throttle, it’s dead :(

Re: 78Honda hobbit new carburetor was installed successfully, then

Do you have spark?

Re: 78Honda hobbit new carburetor was installed successfully, then

the short burst could be some backup or blowback. it can happen if for example the gas is leaking thru the carb and pooling inside or conversely if it's not got enough fuel (is gas on?) als happens if the spark's erratic and not at the right timing, I'm suspecting tho the new carb is maybe leaking and flooded it, i'd check spark and see if any liquid comes out the pipe or blows out when the plug's out. or maybe just no flow, so you can check the drain bolt under the carb while it's all still assembled.

Re: 78Honda hobbit new carburetor was installed successfully, then

Yes, spark is new. I just pulled it out and looked at, seems to be a good shape with no dirty stuff on it. I also checked the fuel line and unattached the carburetor. I didn’t see anything wrong or leaking visually. Remounted the cab and reattached the fuel line... And still the same, when paddled, engine makes low roaring sound. When I stopped paddling, it stopped :(

Re: 78Honda hobbit new carburetor was installed successfully, then

I mean have you verified that the spark plug is actually firing as you pedal? See the "Basic troubleshooting" section of Fred's Guide. (edited)

Re: 78Honda hobbit new carburetor was installed successfully, then

Might of blown off crankseal, variator side. Id replace both but look under clutch bell first.

Re: 78Honda hobbit new carburetor was installed successfully, then

Spark is good, just tested it. Unlike before, the engine makes low and loud noise. Paddle is harder to step now....

Re: 78Honda hobbit new carburetor was installed successfully, then

> Ed H wrote:

> -------------------------------------------------------

> Spark is good, just tested it. Unlike before, the engine makes low and

> loud noise. Paddle is harder to step now....

Pedal a bike and paddle a boat . ;)

Re: 78Honda hobbit new carburetor was installed successfully, then

On the video it sounds pretty normal to me tbh. Up until ~15sec it sounds like the throttle is open, then it sounds like the throttle is closed (less "throaty")

Re: 78Honda hobbit new carburetor was installed successfully, then

Beach Club Nick /

Video sounds totally normal. Maybe you're describing a backfire that blew one of the crankshaft seals out. Now it doesn't run because the crankshaft seal is sitting behind the variator or flywheel instead of in the case. That's my guess at least

Re: 78Honda hobbit new carburetor was installed successfully, then

Is your decomp, properly seated? Pull the sparkplug out and re attach it to the boot and rest it on your cylinder. When you kick the bike over it should make a spark visibly from the tip of the plug.

Check that before you go removing any flywheels to inspect the seals.

Also, you replaced the carb. Why? Was the original broken? What kind of carb did you replace it with? What jetting is in that carb?

Re: 78Honda hobbit new carburetor was installed successfully, then

Agreed, sounds like it's just turning over normally and not firing. If it's got fuel which sounds like you've verified (tho I'd check w starter fluid, if it goes on starter fluid and not otherwise that's sure check it's a fuel issue. And spark if you got spark and timing isOK, then youre at compression. Check decomp and check compression, you can loosely gauge it with a thumb over the plug hole, plug out, and it should puff your finger off pretty confidently. If that's all ok, it's bottomed compression, nicks guess is a good one

Re: 78Honda hobbit new carburetor was installed successfully, then

Thanks for all the info! Will check into these possibilities...

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