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

Shop Now

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

Farmall & IHC Tractors Discussion Forum
:

F-12 High Compression Piston Question??

Welcome Guest, Log in or Register
Author 
Mike Androvich

11-25-2003 14:35:54




Report to Moderator

I am rebuilding a F-12 engine and since the original pistons were bad, I decided to install a set of high compression pistons I had laying on the shelf. My question is which way to put them on the rod? The tops of these pistons have a sloped side and a notched side. Which side towards the spark plug? The sloped side makes the piston stick above the top of the block and the notched side puts the top of the piston flush with the top of the block. I would assume the notched side would be towards the plug, which gives a larger ignition volume, but I am not sure. Anybody out there know which way? Thanks a bunch!

[Log in to Reply]   [No Email]
Farmall Daddy

11-26-2003 13:39:57




Report to Moderator
 Re: F-12 High Compression Piston Question?? in reply to Mike Androvich, 11-25-2003 14:35:54  
My Dad did this once to an F-14. One thing to do before you try tightening anything down, is put one piston in the motor, connected like a normal piston, put the head on, and turn the motor over by hand. If it picks the head up, then the piston is backwards. Do the same thing so you don't bend your valves if it doesn't work either ways. Best of luck with it!!



[Log in to Reply]  [No Email]
Karl Olmstead

11-26-2003 12:16:17




Report to Moderator
 Re: F-12 High Compression Piston Question?? in reply to Mike Androvich, 11-25-2003 14:35:54  
What you're describing doesn't make sense to me, Mike. The piston's the same height regardless of which way it is installed; the only thing that should change is whether the part of the piston that sticks up is on the valve side of the cylinder head or the other side. In the F-14, the part of the piston that sticks up above the block fits into the recessed portion of the head that has the valves. I haven't seen one, but from what Justins tells me, the F-14 head is like that of the A/B/C engine.. the valves are recessed and the other half of the combustion chamber is flush with the block. The F-12 has that huge domed combustion chamber, so it wouldn't matter which side the piston 'bump' went on. Pistons usually have an arrow on the side intended to be forward.

[Log in to Reply]  [No Email]
ET

11-26-2003 08:07:39




Report to Moderator
 Re: F-12 High Compression Piston Question?? in reply to Mike Androvich, 11-25-2003 14:35:54  
Look at the chamber in the head if you put them in backwards they will hit the head.



[Log in to Reply]  [No Email]
justin

11-25-2003 16:09:36




Report to Moderator
 Re: F-12 High Compression Piston Question?? in reply to Mike Androvich, 11-25-2003 14:35:54  
The pistons you are describing are actually F14 pistons.. F12 high altitude pistons are just a full piston with a longer compression distance.



[Log in to Reply]  [No Email]
Mike Androvich

11-26-2003 19:24:19




Report to Moderator
 Re: Re: F-12 High Compression Piston Question?? in reply to justin, 11-25-2003 16:09:36  
Thanks for the ideas. I have come to the conclusion that I am putting F-14 pistons into a F-12 block. I had forgotten that when I rebuilt a F-14 about 20 years ago the head indeed has a portion that was flat to the block, making the pistons only able to go one way. Since I am putting F-14 pistons into an F-12 head, there should be clearance with the piston in either orientation. I am going to install them with the notch towards the spark plug and see what happens. Thanks again guys for all the help and ideas!

[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