Honda Hobbit not Starting

Andrew Leone /

I'm new to mopeds in general (quite frankly, new to working on any type of engine except for the occasional carb cleaning).

So, I purchased a 78 honda hobbit that wasn't/isn't running.

I first replaced the carb and the reed valves.

Checked for spark (there is spark).

Checked compression (I get about 100 psi reading both opened throttle and closed).

Fuel is getting to the carb (I checked the bowl).

I sprayed starter fluid into the air intake and does not do anything.

I sprayed starter fluid into the chamber, replaced the spark plug and it fired but would not do anything more.

I removed the muffler thinking perhaps it was clogged up and not allowing air flow, still not starting.

It seems to me that air is not being sucked through the carb as I do not feel any fuel on the spark plug when I remove it.

I then replaced the piston and rings because why not and seemed like fun at the time.

No change.

I put the muffler back on and still no change (compression still at 100 psi).

What should I do next (yes, i realize I'm opening myself to a witty joke or two).

Re: Honda Hobbit not Starting

Points clean and gaped right? Timing right?

Re: Honda Hobbit not Starting

Replaced the carb with what?

Re: Honda Hobbit not Starting

Andrew Leone /

Replaced the carb with a new carb.

If it were the carb, it should still fire when I sprayed into the air intake right?

Re: Honda Hobbit not Starting

Andrew Leone /

No, I did not. It's getting spark so shouldn't that indicate that that the points are at least ok?

Timing: I didn't touch the timing. Could it be that far off that it won't at least fire?

Re: Honda Hobbit not Starting

Dirty30 Dillon /

Turn the motor over with a drill and I bet it starts.

This sounds like your replacing everything while you just can't start via pedals

Re: Honda Hobbit not Starting

Dirty30 Dillon /

You can't "time" a stock hobbit. The stator is fixed in place.

Re: Honda Hobbit not Starting

Andrew Leone /

Interesting, I'll give it a shot.

Keep in mind, I can get 100 psi compression and spark with peddling. Is that not satisfactory?

Re: Honda Hobbit not Starting

Dirty30 Dillon /

If you can register spark and compression, than that's not your issue.

I would suspect mis-installed reeds if your plug is not wet at all

Re: Honda Hobbit not Starting

Andrew Leone /

That was one of my original suspicions but I replaced them with new and they operate as I would expect them to (they open with little resistance when pressing them with my finger). Unless i put them in upside down (which I didn't), I couldn't have installed them wrong correct?

Could I test this by removing the reeds (I'll use the old reed assembly) so that it's completely open? Then test to see if it's pulling fuel through?

Re: Honda Hobbit not Starting

> Andrew Leone Wrote:

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

> Could I test this by removing the reeds (I'll use the old reed assembly)

> so that it's completely open? Then test to see if it's pulling fuel

> through?

Sans reeds, pressurizing the chamber will be impossible as it will always be able to vent/draw from the atmosphere; this in turn would prohibit you from making it through a full cycle (so you wouldn't be able to tell anyway). Reeds are so easy to check, I have to agree with Dillon here - that's first (could be pinched, snapped, covered in sealant, etc.).

I assume from your first post that you're using an aftermarket carburetor and running premix? The assessment that "air is not being sucked through the carb" seems spot on, which leaves only a few likely culprits: reeds, intake, carb (I assume you're testing this with any air filters removed). Keep us posted.

Re: Honda Hobbit not Starting

Crank seals.

Re: Honda Hobbit not Starting

I’m quite new to mopeds as well and also recently got a hobbit...

Had mine running fine for a few days when I got it, then suddenly it did not want to start.

In my case the flywheel was not on tight enough thus not spinning to help the bike turn over. I know it’s a long shot but it might be worth checking

Re: Honda Hobbit not Starting

U replaced the carb?? With an aftermarket keihin clone off of something like eBay?? The two I tried years ago were untuneable!! I have two oem ones that have been sitting clean in a hobbit carb box. Pm me if u want to buy one . Or simply post for one in the buy sell. If it's not ur seals it's the most likely culprit. U can replace the seals without disassembling the case if u carefully drill a sheetrock screw into the body of the seal without scoring either the crank or the case and use the screw to pull out the seal. Then press in the appropriate seals that treatland or does cycles can sell you with an appropriate ly sized socket.

Re: Honda Hobbit not Starting

Andrew Leone /

I'm leaning toward the crank seals after hearing you and DPC suggest it.

I'm going to try your suggestion.

Re: Honda Hobbit not Starting

Andrew Leone /

I have tested with the air filter removed, and spraying starter fluid into it with no results.

Regarding the reeds, I replaced them but even the old (existing) reeds seemed to be fine.

There was mention of the crank seal potentially being bad which makes sense to me.

Re: Honda Hobbit not Starting

I say this everyday I try to post about mopeds that won't run: read about two stroke leak down tests and make a leak down tester. And use it. That's exactly why somebody invented it: diagnose and fix air leaks. They are incredibly easy to make and use.

Re: Honda Hobbit not Starting

What we need here is a repair section...

Re: Honda Hobbit not Starting

> DPC Ryan Wrote:

this

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

> Crank seals.

what gives it away is itll pop if ya put gas in the cylinder, but wount have any pull/vacumn to suck in fresh fuel thru the carb.. . u can leave the motor n just change the seals from the exterior.

Re: Honda Hobbit not Starting

15271905647056932683847815079608.jpg

. 14 mm at end of gauges to spark plug hole. Disconnect exhaust and intake. Get help.plugging holes with fingers but some corks or other might hold TOTALLY, and have 7 psi flowing in. Spray dilute baby shampoo over engine head gasket base gasket seals if u suspect a case leak everywhere and watch for expanding bubbles. It passes if it holds 7 psi with no bubbles. If it passes the likelihood of a leak is very low. Some folks will say that a classic leak down also instead of pumping air in at 7 psi creates a 7 psi vacuum. So there are various vacuum devices at say harbor freight which u can rig to do that if u want to go both ways. I can't argue that both ways is even better. Because it is.

Or alternatively spray some combustible substance like brake or carb cleaner. Please don't do that in NorCal so I have zero chance of having to have to take care of you in our burn unit.

Re: Honda Hobbit not Starting

Andrew Leone /

Subtle hint that this should have been in the repair section... Apologies

Re: Honda Hobbit not Starting

Don't sweat it

Re: Honda Hobbit not Starting

Andrew Leone /

I'm going to try this method (pressure test, not the combustible).

Re: Honda Hobbit not Starting i got spark compression gas but

Carlos polanco /

spark plug dry seems like gas wont go to the reels

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