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

Ford 9N, 2N & 8N Discussion Forum
:

Compression testing removed from tractor

Welcome Guest, Log in or Register
Author 
Ratface

01-27-2008 17:56:01




Report to Moderator

I have an engine I plan to swap in the spring. It's basically the block, oil pan and head. No exhaust manifold, waterpump, distributor, nothing else attached. I decided to do a compression test on it. I hear and can feel what seems like good compression. I get good blowby with the finger over the hole test. My gauge is the screw in kind. I am turning the engine by hand with a socket wrench. I can't get the gauge past 30psi no matter how long I turn the engine. A wet test showed an insignificant improvement, maybe one point. I put the gauge on my air compressor and it measures 90psi instantly. On the wet test I also noticed some oil dripping from the exhaust passages or are those intake passages? Is this an accurate test or do I need the manifold and carb on as well as the starter to crank with a battery.Is this a crappy engine?

[Log in to Reply]   [No Email]
Dunk

01-29-2008 15:22:30




Report to Moderator
 Re: Compression testing removed from tractor in reply to GB in MT., 01-27-2008 17:56:01  

mArK Pearce said: (quoted from post at 16:50:50 01/29/08) Danny,
I live in Lake Charles, La. SouthWest corner of Louisiana. At times I would like to move away from here to a better place but everywhere has their own set of problems. I like living close to water and seafood/shrimp. I jus love my boiled crawfish, shrimp and beer, in about that order too.

Yep, they got a lot of nice folk over in Vidor, Tx. And I sure would like to go on vacation to Colorado. We have been saving up our change for a train trip. Alnost have our water bottle full now. I hear Colorado is THE place to go for a train trip.
Mark.


Makes me wish I liked to travel.

"When I get off of this mountain, you know where I want to go?

Straight down the Mississippi river, to the Gulf of Mexico

To Lake Charles, Louisiana, little Bessie, girl that I once knew

She told me just to come on by, if there's anything she could do

Lyrics, The Band, "Up On Cripple Creek

[Log in to Reply]  [No Email]
OKDAD

01-29-2008 15:08:36




Report to Moderator
 Re: Compression testing removed from tractor in reply to Chris Watkins, 01-27-2008 17:56:01  
Mark...There are many train choices in CO but IMHO the Durango & Silverton is the best. Beautiful country and all steam power! :D



[Log in to Reply]  [No Email]
Bob

01-28-2008 08:32:17




Report to Moderator
 Re: Compression testing removed from tractor in reply to Ratface, 01-27-2008 17:56:01  
If you want to see what's "leaking", do a "leakdown test".

In your situation, this will probably be more informative than a compression test.

Of course, both the compression and leakdown numbers will look a LOT different AFTER it's been installed and WORKED for a few hours!



[Log in to Reply]  [No Email]
teddy52food

01-28-2008 06:25:06




Report to Moderator
 Re: Compression testing removed from tractor in reply to Ratface, 01-27-2008 17:56:01  
I would think if they are all 30 # when turning by hand, it should be good. Turning it that slow would show up a weak one easier than using the starter.



[Log in to Reply]  [No Email]
Dell (WA)

01-27-2008 19:25:55




Report to Moderator
 Re: Compression testing removed from tractor in reply to Ratface, 01-27-2008 17:56:01  
Rattsie..... ....ya can't turn engine fast enuff by hand for compression test, gotta be twisted by electric starter motor. Don't need manifold or carb. Excess oil from "wet test" could be coming out either intake or exhaust..... ..Dell



[Log in to Reply]  [No Email]
Tom43

01-27-2008 19:05:33




Report to Moderator
 Re: Compression testing removed from tractor in reply to Ratface, 01-27-2008 17:56:01  
A compression test on a cold engine is next to meaningless.



[Log in to Reply]  [No Email]
mArK pearce

01-27-2008 23:42:11




Report to Moderator
 Re: Compression testing removed from tractor in reply to Tom43, 01-27-2008 19:05:33  
Guys, I bought an outboard engine a while back for six hunnerd bucks. It's a 1993 30hp Tohatsu electric start. Anyway, when looking at it to purchase it I brought my comp tester along. The motor looks brand new sept for some sun bleaching on the cowling. I got there and the guy had no spark plugs but found some ones that were the wrong plugs for it. He recommended not to run it long on the plugs he did find. Long story short. I did a compression test on the thing and forgot to open the throttle and the engine was cold as a cucumber. The darn thing compressed out at 150psi on both cylinders. The guy, Vince Eves, a real nice and honest fellow from Vidor Tx. So I bought the darn thing. Got it home and hung it on the back of my boat and forgot about it for about three months. Really, just had ta hide it from the wife for a while!!!! She wants to commit me now for too many hobbies. My Brother one day said "howed that motor run?". I told him I didn't know. So we went and put some good gas in her and it fired right off with the new sparkies I had bought. Then did another(correct) comp test when warmed up. Low and behold it compressed at 150psi on both cylinders again. I always thought 150psi was unheard of on an outboard. Maybe it just me and I have been with junk motors all my life. So what everyone says out there is the motor absolutly has to be warmed up? How do they test brand new engines from the factory? Do they run em all to operating temp and then do a test? Or do they test em cold? Or do they even test em at all because the rings have not seated yet on the new engine? Just kickin the idea around so I'll understand a bit better.


Mark.

[Log in to Reply]  [No Email]
trucker40

01-28-2008 12:09:20




Report to Moderator
 Re: Compression testing removed from tractor in reply to mArK pearce, 01-27-2008 23:42:11  
They use dynos to test new motors.



[Log in to Reply]  [No Email]
Danny in CO

01-28-2008 10:17:18




Report to Moderator
 Re: Compression testing removed from tractor in reply to mArK pearce, 01-27-2008 23:42:11  
mArK,

Where are you located? I grew up in Nederland and have been to Vidor many times.

Danny



[Log in to Reply]  [No Email]
mArK Pearce

01-29-2008 11:50:50




Report to Moderator
 Re: Compression testing removed from tractor in reply to Danny in CO, 01-28-2008 10:17:18  
Danny, I live in Lake Charles, La. SouthWest corner of Louisiana. At times I would like to move away from here to a better place but everywhere has their own set of problems. I like living close to water and seafood/shrimp. I jus love my boiled crawfish, shrimp and beer, in about that order too.
Yep, they got a lot of nice folk over in Vidor, Tx. And I sure would like to go on vacation to Colorado. We have been saving up our change for a train trip. Alnost have our water bottle full now. I hear Colorado is THE place to go for a train trip.


Mark.

[Log in to Reply]  [No Email]
Hobo,NC

01-28-2008 04:45:23




Report to Moderator
 Re: Compression testing removed from tractor in reply to mArK pearce, 01-27-2008 23:42:11  
I check'em cold all the time,,, never had a problem,,, I spec the hot check comes from the slow turn'n 6V system,,, they need all the help thay can git,,, It would B best to use a 12V jump rite to the starter,,, cold or hot it would spin'er up e nuff to git a good reading,,, goes to show ya if you repeat it enuff it becomes acceptable,,, no questions asked



[Log in to Reply]  [No Email]
old

01-27-2008 18:23:28




Report to Moderator
 Re: Compression testing removed from tractor in reply to Ratface, 01-27-2008 17:56:01  
Manifold would make no difference, but by hand you can't turn it fast enough to get a good reading. Now if you could say have all the plugs out and really get it to spin over then maybe but even then its iffy



[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