Honda 2.3HP starting issues at night

[lawrence_craig]

Hi all,

I have a weird issue going on with my Honda 2.3HP.

I have read up on all the other posts and followed them.

I have changed the spark plug, the fuel and cleaned the carburettor multiple times but still having issues.

It’s such a strange issue, the engine will start fine during the day (I’m in the Med) but at night it doesn’t start.

Logic would suggest its a temperature issue with the fuel supply getting to the spark however I have cleaned the carb multiple times and changed the fuel and had no luck. I check the spark plug and it’s dry. I then strip the Carb and there’s plenty of fuel in the carb bowl.

I was wondering if anyone had any further solutions or something I’ve missed.

Many thanks,
Lawrence

[jimbunyard]

But is the plug getting spark at night?

If not, I'd guess it's related to humidity or differential expansion, but in the electrical system, typical places to look would be a kill switch or kill switch circuit, or clearance-related systems like spark sensors or magnetos...

[Pete7]

Lawrence, the air screw bleed on top of the fuel cap, is it clean and not creating a vacuum as the temperature drops at night? Easiest way is to try and start it with the fuel cap unscrewed.

Pete

[lawrence_craig]

Originally Posted by Pete7

Lawrence, the air screw bleed on top of the fuel cap, is it clean and not creating a vacuum as the temperature drops at night? Easiest way is to try and start it with the fuel cap unscrewed.

Pete

Hi Pete, would that not mean no fuel in the Carb? When I remove the carb there is plenty of fuel on it

[Rapanui]

Had a very similar issue with my Honda 2.3, also in the Med particularly in the autumn with evening dew. The cause was condensation leaking away some of the spark energy from the HT plug lead so there is not enough left to initiate combustion. The HT lead is of the resistive type conducted through carbon fibres. These are not very robust and tend to break particularly where the spark plug connection is. Pull the spark plug cap from the lead and there is a brass connector which is pushed or screwed into the core of the HT lead. I removed the connector, chopped about 10mm off the lead ( provided there is enough length to do that) and reconnected it, pushed the cap back on, spray lead and cap with WD40 or other water displacing insulant and you should be OK.
If you are old enough, it is a similar problem to the olden days before electronic ignition when cars had contact breakers and distributors and you had to dry the distributor cap and leads and spray to get you going in damp conditions.

[hamburking]

open the vent. Sounds like vacuum in the fuel tank.

Also, put a capful of methyl hydrate into the fuel. That should get any condensation out.

Try higher octane gasoline.

Have you tried giving it choke to start?

[S/V Alchemy]

Originally Posted by Rapanui

Had a very similar issue with my Honda 2.3, also in the Med particularly in the autumn with evening dew. The cause was condensation leaking away some of the spark energy from the HT plug lead so there is not enough left to initiate combustion. The HT lead is of the resistive type conducted through carbon fibres. These are not very robust and tend to break particularly where the spark plug connection is. Pull the spark plug cap from the lead and there is a brass connector which is pushed or screwed into the core of the HT lead. I removed the connector, chopped about 10mm off the lead ( provided there is enough length to do that) and reconnected it, pushed the cap back on, spray lead and cap with WD40 or other water displacing insulant and you should be OK.
If you are old enough, it is a similar problem to the olden days before electronic ignition when cars had contact breakers and distributors and you had to dry the distributor cap and leads and spray to get you going in damp conditions.

Having troubleshot (troubleshooted?) an Atomic 4's antique ignition system, this sounds quite plausible. Good luck.

[morribabes]

Get an old spark plug and set the gap to around 3mm. Use this to check the spark. If it won't produce a spark you have a compromised ignition system. Check for good earths, HT lead, plug cap, coil etc etc.

[Mike Banks]

Turn on a bright light. Start the engine. Turn off the light.

If that does not work, you probably have a fuel supply problem--from the tank to the carburettor. My guess is the fuel pump diaphragm, or the pulse hose which operates the pump, but it could be anything. It is a process of elimination.

[Kita]

Originally Posted by lawrence_craig

Hi Pete, would that not mean no fuel in the Carb? When I remove the carb there is plenty of fuel on it

Not really,because with a restricted vent that is on the gas cap fuel will flow just very slow..I have on of these that the vent clogs up on a regular basis, it will surge & eventually stall unless I go adjust it ... to prove it I waited for the sturge to start then just opened the cap & it was almost an immediate Improvement. Try it with the gas cap off just for the heck of it if you do have spark.

[Cpt Pat]

Vapor lock?

[Boatyarddog]

Originally Posted by lawrence_craig

Hi all,

I have a weird issue going on with my Honda 2.3HP.

I have read up on all the other posts and followed them.

I have changed the spark plug, the fuel and cleaned the carburettor multiple times but still having issues.

It’s such a strange issue, the engine will start fine during the day (I’m in the Med) but at night it doesn’t start.

Logic would suggest its a temperature issue with the fuel supply getting to the spark however I have cleaned the carb multiple times and changed the fuel and had no luck. I check the spark plug and it’s dry. I then strip the Carb and there’s plenty of fuel in the carb bowl.

I was wondering if anyone had any further solutions or something I’ve missed.

Many thanks,
Lawrence

Oh yes, now that we call gaseous fuel "Molecules of Freedom".
They will only work during the day when they're excitable.