Welcome! Please use the navigational links to explore our website.
PartsASAP LogoCompany Logo (800) 853-2651

Shop Now

   Allis Chalmers Case Farmall IH Ford 8N,9N,2N Ford
   Ferguson John Deere Massey Ferguson Minn. Moline Oliver

Attention Forum Users: On the 28th of December 2023 at 9:00am Central Time, we will be taking the forums down for maintenance while we prepare the new forums for your use. Please click here for more information.

Case Tractors Discussion Forum
:

Case 900B Diesel valve spring settings

Welcome Guest, Log in or Register
Author 
Bryan Flath

05-05-2004 12:21:17




Report to Moderator

Good Afternoon Everyone: I have just recently removed the 3 heads on a 900B Diesel and replaced the head gaskets. After putting it together and torqueing to specs, it seems to run rough and gives a few pops every now and then. Just last night I retorqued the head bolts again but now don't know how to set the valve spring clearance. Some are very tight and some have at least 1/8" play on them. Can anyone give me some ideas on why it is running so rough and also be able to talk me through setting the valve springs. P.S. The tractor starts real good and has great power, but just runs rough at idle and high speeds. Thank you for your time.

[Log in to Reply]   [No Email]
Jim B

05-05-2004 15:18:32




Report to Moderator
 Re: Case 900B Diesel valve spring settings in reply to Bryan Flath, 05-05-2004 12:21:17  
When adjusting an engines "valves" you do not actually adjust the 'valve spring clearance' nor are you 'setting the valve springs' >> what you adjust is the clearance between the tip of the stem valve itself and the valve contacting surface on the rocker arm > which is called the valve clearance. Sometimes this is called adjusting the 'tappets'. This clearance is necessary in order to assure the valve(s) ALWAYS completely close (by the spring force) throughout the temperature range of normal operation. In other words ... the required clearance allows for normal thermal expansion of all components involved. The adjustments are usually specified to be accomplished on a HOT engine and it's certainly more accurate and faster to do this while the engine is running. Therefore, it is supposed to be done upon initial warm-up after a rebuild before the machine leaves the garage. Never run an engine with a tight valve because the valve may get burned (destroyed) if it cannot close completely > usually determined if it runs rough and is noisy. Apparently when you reassembled your 900 you mixed some of the push-rods from it�s original mating valve! When there is a valve with an 1/8" of clearance (loud tapping noise) there may be another that is too tight by an 1/8" which will prevent that cylinder from producing full power and will quickly ruin the related valve, especially if it's an exhaust valve. Certainly it will make the engine run rough.
Now that I scared you a little (I hope) the subject required adjustments are quite simple >> On the end of the rocker arm, where it contacts the valve stem, you will see a special bolt (tappet) with a locknut on it. Loosen this locknut, and while holding a feeler gauge in the space between the valve and the tappet make the adjustment by turning the tappet with a screwdriver. Then tighten the locknut without letting the tappet turn. Correctly adjusted the feeler gauge should be snug but not tightly locked in place. Remember the engine is Hot and running when you do this. Normally the specs are different for the intake and the exhaust valve due to the greater operating temp of the exhaust valve. Sorry, I don't know what Case specifies for a 900B. Good Luck and have Fun.

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

Hop to:


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 ]

Home  |  Forums


Copyright © 1997-2023 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