Re: marvel schebler carb

Posted by Joe (Wa) on May 29, 2004 at 18:44:19 from (65.126.49.81):

In Reply to: marvel schebler carb posted by glenn fowler on May 29, 2004 at 11:45:16:

Wow. Too much info! After my 2 cents worth is a description of the idle & starting circuit functions. See if you can figure out the problem.

This appears to be a throttle valve and/or idle mixture problem.

Float adjustment isn't an issue in starting if fuel bowl has gas in it. If the bowl has gas and the engine vacuum is ok, some things to check:

1. The throttle plate must be installed with the angle identification mark facing up.

2. The idle jet must be fully seated and w/o any tool marks in the slot that can distort the orifice.

For starting and idling the throttle valve should be set slightly open with the edge between the primary and the secondary idle orifices.

With the valve in this position, the air pressure (manifold vacuum) at the primary is lower than the air press in the fuel bowl and fuel is force from the bowl up the idle fuel passage passing through the idle jet.

Air for atomizing enters at the idle adjusting needle seat mixing with the gas. The atomizing process is repeated at the fixed secondary idle orifice.

The rich mixture of gas & air emerges from the primary idle orifice and is reduced to correct proportions by the air that passes around the slightly open throttle valve.

The idle mixture screw can either control the air (air adjusting) or the fuel (fuel adjusting) to provide the correct mixture for starting and idling. Most MS are air adjusting as in the pix, turn cw to richen, ccw for leaner. Fuel adjusting is the opposite.

Joe

Follow Ups:

• Re: Re: marvel schebler carb Ron 05:52:20 05/30/04 (1)
  • Re: Re: Re: marvel schebler carb Joe (Wa) 10:18:50 05/30/04 (0)

Post a Followup Name: E-Mail: Subject: Re: Re: marvel schebler carb Comments: Optional Link URL: Link Title: Optional Image URL: Email Notification: If you check this box, email will be sent to you whenever someone replies to this message. Your email address must be entered above to receive notification. This notification will be cancelled automatically after 2 weeks.

TRACTOR PARTS	TRACTOR MANUALS

We sell tractor parts!  We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]