Hi, Maybe I should have read through the original problem better, but, if you are getting gas into the oil and yet it is not smoking a black smoke, the problem is not in the carburetor. On most all gasoline engines, with carburetors, a fuel pump is employed. It mounts on to the engine block and is usually driven or actuated by a lobe on the camshaft. It is sealed, usually by the diaphragm, to prevent gasoline from entering the engine block. As the pump ages, the diaphragm, itself, develops small cracks that eventually allows leakage. During the initial periods of leakage, there is still enough fuel pressure that allows the engine to run. As load increases, the demand for more fuel also increases. Lack of enough pressure will cause the engine to run lean, not enough fuel getting to the carburetor. The engine will then run rough until it eventually dies from lack of fuel. It will still crank back up and idle under no load. As the diaphragm in the pump continues to deteriorate, less fuel goes to the carburetor and more fuel goes inside the engine block, Eventually, the diaphragm becomes so cracked that it can't draw enough fuel to pump it anywhere and the engine won't run at all. My initial suggestion, if you can find one, is to replace the fuel pump with a new one, or, at least a rebuilt one. The Onan people are just about out of qualified sales people for the older Onans. Plus, after so many years, they quit making the parts all together. I have quit working on them. Not that they are difficult, but, because trying to get parts are a nightmare at best.
I wish you luck and hope this helps, Jack On Fri, Mar 27, 2009 at 12:47 AM, bushwood <[email protected]> wrote: > > As long as it has taken to reply, I apologize. However, I do need to > replace one of my plug wires. Does anyone have any plug wires they > would be willing to part with/sell? I have the shielded, screw in > type. > > The gen set is a '73 Onan 6.5kw MCCK. > > Thank you > > [email protected] > > > > > On Jan 28, 3:47 am, flitebuilder <[email protected]> wrote: > > Only way to get fuel in the oil is through the small gap between the > > piston rings and cylinder or if the valve stem on the intake is > > leaking. > > Usually it is the opposite where the oil gets into the cylinder or > > intake mainfold through the leaking parts. > > > > One other way this could happen is if the choke is flooding the engine > > then when the plugs short out, the engine shuts down, but still turns > > over a few more times. > > This draws in a bit more fuel that remains unburned. This fuel will > > seep down into the crank case very slowly, no matter the age of the > > engine. > > > > My suggestion would be to repair the fuel delivery problem, and keep > > replacing the oil in the the crank case. when fuel problem is fixed, > > run the generator on a good load with new oil for > > an hour or so and see if fuel still gets into the oil. > > > > Good luck, > > > > victor > > > > On Jan 22, 4:24 pm, "Perry & Cindi" <[email protected]> wrote: > > > > > > > > > Not good having fuel in the oil. It dilutes the oil and you loose > > > lubrication properties and can play havoc with seals especially in > older > > > engines. I will let a more knowledgeable gas engine person give you > > > suggestions on what to do to repair the issue. > > > I do not think you should be running the engine until you fix the fuel > > > leaking problem. > > > Good luck > > > Capt. Perry > > > > > -----Original Message----- > > > From: [email protected] [mailto: > [email protected]] > > > > > On Behalf Of bushwood > > > Sent: Thursday, January 22, 2009 3:59 PM > > > To: UnifliteWorld > > > Subject: [UnifliteWorld] Re:Onangenerator > > > > > Well I played with it again today. I changed fuel filter, sprayed > > > carb cleaner down carb throat, checked plugs and they are moist. I > > > pulled dipstick and I can smell fuel in the oil. Despite what I did, > > > it still runs same. I haven't pulled the carb apart, yet...... > > > > > On Jan 19, 1:03 pm, bushwood <[email protected]> wrote: > > > > I will check all again. It's just odd that one day it works great. > > > > The next day it starts up fine (manual choke) and then fails with a > > > > load. I checked the smoke/exhaust when this was occurring and did > not > > > > see anything out of the ordinary. The water coming out of the > exhaust > > > > did not seem to have any excess 'rainbowing' from unburned fuel, but > > > > then again, I've been wrong before. > > > > > > Thanks and will keep you posted. > > > > > > On Jan 19, 2:48 pm, waterguy <[email protected]> wrote: > > > > > > > >RPMs never recovered after this, > > > > > > even with no load. > > > > > > > > I think I can smell some fuel. Is it possible the carb float > stuck > > > > > > and it's running way too rich? The genny has never been a > problem. > > > > > > Are there any tricks to check before addressing the carb? > > > > > > > > Thanks > > > > > > > All excellent suggestions. I'd first look at the fuses in the > control > > > > > unit (box on the left side of the genset - "left" as you stand at > the > > > > > generator end of the unit, flywheel farthest away from you). The > > > > > electric choke is controlled by one of those fuses (sorry - don't > know > > > > > which one offhand). Pull each one out and check with an ohmmeter - > > > > > I've had fuses blow right under the cap where you couldn't see it. > > > > > > > I had this problem - rough running, fuel smell, gray-to-black > smoke, > > > > > and it was the blown fuse that kept the electrically-heated choke > > > > > stove from being energized, warming up and pulling the choke off.- > Hide > > > quoted text - > > > > > > - Show quoted text - > > > > > No virus found in this incoming message. > > > Checked by AVG -http://www.avg.com > > > Version: 8.0.176 / Virus Database: 270.10.12/1910 - Release Date: > 1/22/2009 > > > 6:28 PM- Hide quoted text - > > > > > - Show quoted text -- Hide quoted text - > > > > - Show quoted text - > > > -- Jack Smith [email protected] --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "UnifliteWorld" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/UnifliteWorld?hl=en -~----------~----~----~----~------~----~------~--~---
