Welcome! Please use the navigational links on your left to explore our website.

Company Logo Shop Now
   Allis Chalmers Case Farmall IH Ford 8N,9N,2N Ford
   Ferguson John Deere Massey Ferguson Minn. Moline Oliver
 
Marketplace
Classified Ads
Photo Ads
Tractor Parts

Community
Discussion Forums
Project Journals
Tractor Town
Your Stories
Show & Pull Guide
Events Calendar
Hauling Schedule

Galleries
Tractor Photos
Implement Photos
Vintage Photos
Help Identify
Parts & Pieces
Stuck & Troubled
Vintage Ads
Community Album
Photo Ad Archives

Research & Info
Articles
Tractor Registry
Tip of the Day
Safety Cartoons
Tractor Values
Serial Numbers
Tune-Up Guide
Paint Codes
List Prices
Production Nbrs
Tune-Up Specs
Torque Values
3-Point Specs
Glossary

Miscellaneous
Tractor Games
Just For Kids
Virtual Show
Museum Guide
Memorial Page
Feedback Form

Yesterday's Tractors Facebook Page

Related Sites
Tractor Shed
TractorLinks.com
Ford 8N/9N Club
Today's Tractors
Garden Tractors
Kountry Life
  
Discussion Forum

"Not a Moron" Fuel Valve Question?

Welcome Guest, Log in or Register
Author 
Donnie

06-04-1998 19:17:54




Report to Moderator

In reading the question concerning leaving the fuel valve on sediment bulb open and discovering gas in the crankcase, I have a dumb question, how does the gas leak into the crankcase?

Granted if the float or needle valve don't seal off completely the gas will flood the carburetor. Since most tractor carbs are downdraft it would appear that the carb would have to fill up, then the intake manifold fill up, then perhaps an open intake valve would fill a cylinder, then perhaps the lighter viscosity gas could leak past the rings and seep into the crankcase.

Is this what happens or am I missing something?

[Log in to Reply]   [No Email]
farmer






Report to Moderator
 Re: "Not a Moron" Fuel Valvestion? in reply to  



[Log in to Reply]  [No Email]
steve vermilya

06-06-1998 18:02:43




Report to Moderator
 Re: Re: in reply to farmer, 06-05-1998 06:48:32  
: : In reading the question concerning leaving the fuel valve on sediment bulb open and discovering gas in the crankcase, I have a dumb question, how does the gas leak into the crankcase?

: : Granted if the float or needle valve don't seal off completely the gas will flood the carburetor. Since most tractor carbs are downdraft it would appear that the carb would have to fill up, then the intake manifold fill up, then perhaps an open intake valve would fill a cylinder, then perhaps the lighter viscosity gas could leak past the rings and seep into the crankcase.

: : Is this what happens or am I missing something?

: OK, so your not a moron, and yes, your right in your description of what can happen. Many carbs though have a porous bronze bleed out drain in the bottom. You haven't been standing on your head a lot have you ? I think you will find that most tractor carbs are "up"-draft except for side drafts like Deere.
: Have a good one. :)

to : Not a moron....

The probelem you ae referring to is not a stupid question, and happens a lot in older farm tractors. The gas is not geting into the crankcase from the carburetor, period. The gas you are getting into the crankcase is unburned fuel from a rich mixture in the combustion chamber, and combustion itself is forcing it down the cylinder walls because the piston rings are very worn. This also happens frequently when the carb is partially obstructed in one of the low speed circuits, and you are forced to run with the choke partially out in order to make the tractor run properly.....ThisIf you are having this problem..first check the condition of carb...then perform a compression test to determine the condition of the engin...apparently quite worn.A new set of sleeves and rings, with possibly a carb overhaul will cure your problems. Do not run tractor with the oil thinned down with gas....if i can be of any further help feel free to email me...good luck

[Log in to Reply]  [No Email]
steve vermilya

06-06-1998 17:56:39




Report to Moderator
 Re: Re: in reply to farmer, 06-05-1998 06:48:32  
: : In reading the question concerning leaving the fuel valve on sediment bulb open and discovering gas in the crankcase, I have a dumb question, how does the gas leak into the crankcase?

: : Granted if the float or needle valve don't seal off completely the gas will flood the carburetor. Since most tractor carbs are downdraft it would appear that the carb would have to fill up, then the intake manifold fill up, then perhaps an open intake valve would fill a cylinder, then perhaps the lighter viscosity gas could leak past the rings and seep into the crankcase.

: : Is this what happens or am I missing something?

: OK, so your not a moron, and yes, your right in your description of what can happen. Many carbs though have a porous bronze bleed out drain in the bottom. You haven't been standing on your head a lot have you ? I think you will find that most tractor carbs are "up"-draft except for side drafts like Deere.
: Have a good one. :)

[Log in to Reply]  [No Email]
Chris G.

06-05-1998 19:45:04




Report to Moderator
 Re: Re: "Not a Moron" Fuel Valve Question? in reply to farmer, 06-05-1998 06:48:32  
: : In reading the question concerning leaving the fuel valve on sediment bulb open and discovering gas in the crankcase, I have a dumb question, how does the gas leak into the crankcase?

: : Granted if the float or needle valve don't seal off completely the gas will flood the carburetor. Since most tractor carbs are downdraft it would appear that the carb would have to fill up, then the intake manifold fill up, then perhaps an open intake valve would fill a cylinder, then perhaps the lighter viscosity gas could leak past the rings and seep into the crankcase.

: : Is this what happens or am I missing something?

: OK, so your not a moron, and yes, your right in your description of what can happen. Many carbs though have a porous bronze bleed out drain in the bottom. You haven't been standing on your head a lot have you ? I think you will find that most tractor carbs are "up"-draft except for side drafts like Deere.
: Have a good one. :)

Farmer is right, it's not a down draft carb. I still can't see the gas getting into the crankcase.

[Log in to Reply]  [No Email]
Chris G.

19:45:04




Report to Moderator
 Re: Re: "Not a Moron" Fuel Valve Question? in reply to farmer, 06-05-1998 06:48:32  



[Log in to Reply]  [No Email]
[Options]  [Printer Friendly]  [Posting Help]  [Return to Forum]   [Log in to Reply]

Hop to:


TRACTOR PARTS TRACTOR MANUALS
Fast Shipping!  Most of our stocked parts ship within 24 hours (M-Th). We have the parts you need to repair your tractor - the right parts. Our fast shipping, low prices and years of research make us your best choice when you need parts. Shop Online Today. [ About Us ]

Home  |  Forums


Copyright © 1997-2019 Yesterday's Tractor Co.

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy

TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters

Website Accessibility Policy