Go Back  Offshoreonly.com > Technical > General Q & A
compression/ leakdown test w/ engine torn appart? >

compression/ leakdown test w/ engine torn appart?

Notices

compression/ leakdown test w/ engine torn appart?

Thread Tools
 
Old 03-04-2003, 07:07 PM
  #1  
Registered
Thread Starter
 
Join Date: Apr 2002
Posts: 4,215
Likes: 0
Received 0 Likes on 0 Posts
Default compression/ leakdown test w/ engine torn appart?

I'v got my engines tore down to replace cams, can I do a compression test with the engine torn appart or does it have to be assembled and sealed?
THRILLSEEKER is offline  
Old 03-04-2003, 07:20 PM
  #2  
Registered
 
Turbojack's Avatar
 
Join Date: Sep 2001
Location: Houston, TX, USA
Posts: 2,287
Likes: 0
Received 0 Likes on 0 Posts
Default

When you say torn apart do you mean heads are off? If you heads are still one you can still do a leakdown test. Better of the 2 tests. A compression test needs the cam installed to do correctly.
Turbojack is offline  
Old 03-04-2003, 07:45 PM
  #3  
Registered
Thread Starter
 
Join Date: Apr 2002
Posts: 4,215
Likes: 0
Received 0 Likes on 0 Posts
Default

heads are on, I just want to check and see if I need to replace rings or not while the engines are out.
THRILLSEEKER is offline  
Old 03-04-2003, 08:12 PM
  #4  
I hate the winter!!
Platinum Member
 
Vinny P's Avatar
 
Join Date: Jul 2001
Location: long island, new york
Posts: 2,707
Likes: 0
Received 0 Likes on 0 Posts
Default

As long as the heads are on, it is no problem to run a leakdown test.
Vinny P is offline  
Old 03-04-2003, 08:31 PM
  #5  
Registered
Thread Starter
 
Join Date: Apr 2002
Posts: 4,215
Likes: 0
Received 0 Likes on 0 Posts
Default

check454mag, I am assuming that rocker arms have to be installed and properly adjusted??????
THRILLSEEKER is offline  
Old 03-04-2003, 09:21 PM
  #6  
Charter Member #1171
Charter Member
 
obnoxus's Avatar
 
Join Date: Feb 2001
Location: Clearwater, FL
Posts: 4,019
Received 21 Likes on 16 Posts
Default

nope,,, actually it is easier with them off,,, dont have to worry about getting the cam in the right spot to insure fully closed valve
__________________
I want to live in a world where a chicken can cross the road and not have its motives questioned.
obnoxus is offline  
Old 03-05-2003, 05:47 AM
  #7  
Registered
 
Turbojack's Avatar
 
Join Date: Sep 2001
Location: Houston, TX, USA
Posts: 2,287
Likes: 0
Received 0 Likes on 0 Posts
Default

To do a leakdown test you need to have both valves closed. You screw the leakdown tester in the sparkplug hole. The tester has 2 gauges on it. You have a pressure regulator & adjust the pressure on it. I set mine at 100lbs. You then look at the second gauge. If it shows 85 then you have 15% leakage. The older the motor gets or if it has a problem the number will get lower. Liisten to the intake or exhaust. If you feel/hear air then the valve is not seating & that is where some of the leakage is going.
Turbojack is offline  
Old 03-05-2003, 07:28 PM
  #8  
I hate the winter!!
Platinum Member
 
Vinny P's Avatar
 
Join Date: Jul 2001
Location: long island, new york
Posts: 2,707
Likes: 0
Received 0 Likes on 0 Posts
Default

I agree with TurboJack. But, I will add making sure the piston is on T.D.C. for the cylinder you are checking.
Vinny P is offline  
Old 03-05-2003, 08:06 PM
  #9  
Registered
 
Turbojack's Avatar
 
Join Date: Sep 2001
Location: Houston, TX, USA
Posts: 2,287
Likes: 0
Received 0 Likes on 0 Posts
Default

checkmate- I was told the same but I thought it was to make sure the valves would stay shut. Hopefully someone that may know another reason will chime in.
Turbojack is offline  
Old 03-06-2003, 08:53 AM
  #10  
blown1500
Guest
 
Posts: n/a
Default

Hello, Guys,
The rings seal best at TDC when in good condition. The seal at the bottom of the bore is not usually as good. Also, when the pressure is applied, unless you are at top center or bottom center, the piston will try to go to bottom and could spin unexpectedly.
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
ak
General Q & A
6
10-19-2008 12:33 PM
articfriends
General Q & A
11
02-16-2007 06:22 PM
onesickpantera
General Q & A
6
10-09-2006 08:58 PM
Toffen
General Q & A
1
12-04-2003 07:58 PM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



Quick Reply: compression/ leakdown test w/ engine torn appart?


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.