small engine repair

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Oct 26, 2007 | 07:17 PM

Lee250

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Joined: Sep 2006

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From: Mt. View Hawaii

small engine repair

I am rebuilding an 11hp 4stroke Tecumseh generator engine and was wondering if any one would know about what the piston ring end gap should be. I was going to use the specs for my truck which is .010-.020 but my dad said that since this engine is air cooled that it runs hotter and the gap might need to be bigger. Any advice?

Oct 26, 2007 | 08:39 PM

Buckarcher

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From: Princeton, MN

Try this link, check page 87. Don't know if one of those models are yours, but there are two different specs listed. Like you said and a .07-.17. They seem to only list 4 sets but they are 4 cycle OHV's

http://www.smallenginesuppliers.com/...nformation.pdf

It comes from this page.

http://www.smallenginesuppliers.com/...ine-specs.html

Last edited by Buckarcher; Oct 26, 2007 at 08:42 PM.

Oct 26, 2007 | 11:59 PM

ford2go

Cargo Master

Joined: Apr 2003

Posts: 3,476

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From: Frequently frozen MN

If you find the tecumseh website, I think that they have most of their service manuals online

ford2go

Oct 27, 2007 | 12:00 AM

jake00

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Joined: Apr 2004

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From: NW burbs of chicago

def. look in the service manual

Oct 27, 2007 | 01:39 PM

00BlueOvalRanger

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From: Southern MD

Try here:

http://www.cpdonline.com/692509.pdf

Oct 27, 2007 | 09:28 PM

Octane

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Joined: Apr 2005

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From: Edgerton, WI

Quote:

Originally Posted by Lee250

my dad said that since this engine is air cooled that it runs hotter and the gap might need to be bigger. Any advice?

Your dad is right. Air-cooled engines are built with looser tolorances to allowed for a greater amount of expansion due to the high combustion chamber temps.
I dont know what the gap should be, but hopefully one of those links that the others provided are of some help to you.

Oct 28, 2007 | 07:45 AM

ckal704

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Joined: Nov 2004

Posts: 3,550

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From: Lancaster County PA

Typical ring end gap reject sizes are .035" for either of the two compression rings (top two) and .045" for the oil ring.
If the bore hasn't changed and the rings are new, you'll usually find them to be about .015".
So, if you are anywhere between .015" and .025" that would be considered acceptable and the engine should have ample compression to make the power that you expect.
Just be sure to measure your bore if your ring end gaps appear to be beyond reject. The cast iron rings are designed to wear at a faster rate than the aluminum cylinder (yes, it is true!), but if the cylinder is worn (excessive dirt ingestion through the carb or in the oil), new, standard rings may not help matters much.