EF1000 rough running - without air filter element

classic Classic list List threaded Threaded
4 messages Options
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

EF1000 rough running - without air filter element

mediterranean
Hello everyone, weird problem, well I have my suspicions but would not mind your input...

Friend's EF1000 (not IS or A) runs somewhat rough. Also, some black soot comes out of the exhaust.

Suspected carb so took that to bits and cleaned all the jets (including the one with the near invisible hole!) and TBH there was no dirt to start off with anyway.

No change.

For the hell of it opened up air filter cover to take a look inside. That done, revs increased substantially, generator runs smoothly.

BUT - there was no air filter element inside so that being blocked could not be a problem. Everything else is 100% stock and unmodified, there is nothing obstructing the flow of air inside the filter housing.

The path the air flows is rather contorted and the passageways are not wide. There's also that secondary chamber too, linked to the motor's cooling vanes shroud, not 100% sure re its function but here goes my theory.

I suspect that the lack of air filter is actually disturbing the flow. I suspect that the air flow is subject to very complex harmonics mainly designed to reduce sound levels and the air filter element is a critical part of this. Without it, the flow is self-obstructing in some manner.

Any thoughts? Will just buying an air filter element sort this out? Failing which I will have to drill holes in the side of the filter housing to improve flow otherwise its owner will just discard the housing cover completely.
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: EF1000 rough running - without air filter element

mediterranean
Well I fitted a home made temporary foam filter because I did not have the patience to wait. No change.

So I enhanced the flow of air through the air filter housing, and that worked.

I don't understand how the stock setup could be restrictive, but it was.

Perhaps there's too much petrol being atomised by the carb, so more air was called for.

Not quite happy with the solution, but a solution it is.
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: EF1000 rough running - without air filter element

CycleRob
mediterranean,
 The black sooty exhaust and rough running means the carb is metering the fuel too rich. "Cleaning" the jets mechanically (with thin wires) will make them minutely larger, especially if they were corroded by being stored with 10% Ethanol gasoline. The solution, when you purchase a new air filter element, is to add onto the list both the main and pilot jets.

 Drilling holes in the air filter cover or the air filter housing for more air flow . . . to compensate for damaged main and pilot jets, is a very bad thing. The chambers/tubes/vanes/partitions that make up the airbox interior are the result of very sophisticated rocket science that uses flywheel cooling fan air pressure/flow, the pulsing of the intake stroke air column, harnesses and redirects it to both muffle the sounds and increase the airflow. When you drilled those "relief" holes, ALL of that beneficial dynamic tuning science goes to zero, to be replaced with louder undesirable noises, LESS performance and poor engine throttle response. After the new jets are installed, you can use Duct tape over the drilled holes and black plastic soda caps as a raw material source so a soldering iron can deposit melted plastic as a hole filler.

 It could also be that the float level is too high and/or the float needle seat is corroded/gummed up and leaking when the float is all the way up. Is the carb dripping or weeping fuel with the engine off?
Talent, On Loan, From God  --Rush Limbaugh--
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: EF1000 rough running - without air filter element

mediterranean
Yes you must be right, after giving it some thought I came to the conclusion that the jet orifices must have corroded slightly wider and what with one being barely (if) hair's breadth in diameter, it won't take much.

I did not poke any wire only used spray jet to clean the jets but the generator has definitely been "looked at" in the past so who knows what it's been through.

However it works reasonably well as is and I doubt it's owner could be bothered with taking it any further.
Loading...