Honda Civic / Del Sol (1992 - 2000) EG/EH/EJ/EK/EM1 Discussion

Compression Test

Thread Tools
 
Search this Thread
 
Old Jun 10, 2009 | 02:20 PM
  #1  
civic_driver's Avatar
Thread Starter
Honda-Tech Member
 
Joined: Aug 2005
Posts: 2,582
Likes: 2
From: USA
Default Compression Test

Hey guys,

I just did a compression test on my d16y7 and the numbers I got are 195, 187, 192, 197. Since they are above 135psi and are within 10% of each other I suppose the compression is good, right?

A note to those doing a compression test on 96-00 civics: All you have to do is remove the "fuel pump/(srs unit)" and "(ign coil)" fuses before doing a compression test. Both fuses are under the dash and both are 15amp.

I did 8 cranks/revolutions per cylinder as per the compression gauge manual's recommendation. Well, actually I did 10 but the manual recommends 8.

Last edited by civic_driver; Jun 11, 2009 at 11:38 AM.
Reply
Old Jun 10, 2009 | 05:32 PM
  #2  
civic_driver's Avatar
Thread Starter
Honda-Tech Member
 
Joined: Aug 2005
Posts: 2,582
Likes: 2
From: USA
Default Re: Compression Test

At first I thought the numbers were kind of high for a d16y7 with 70K miles on it. What do you think?

Last edited by civic_driver; Jun 10, 2009 at 05:51 PM.
Reply
Old Jun 10, 2009 | 05:34 PM
  #3  
mynameisChris's Avatar
Junior Member
 
Joined: May 2009
Posts: 115
Likes: 0
From: Canton, Ohio
Default Re: Compression Test

Sounds about right to me.
Reply
Old Jun 10, 2009 | 05:35 PM
  #4  
Targa250R's Avatar
be professional
 
Joined: Oct 2002
Posts: 14,842
Likes: 13
From: Pittsburgh, PA
Default Re: Compression Test

It's fine.
Reply
Old Jun 10, 2009 | 05:44 PM
  #5  
amtheiceman's Avatar
Honda-Tech Member
iTrader: (1)
 
Joined: Sep 2006
Posts: 191
Likes: 0
From: Indianapolis, IN, USA
Default Re: Compression Test

just right
Reply
Old Jun 10, 2009 | 06:22 PM
  #6  
civic_driver's Avatar
Thread Starter
Honda-Tech Member
 
Joined: Aug 2005
Posts: 2,582
Likes: 2
From: USA
Default Re: Compression Test

Wow, I remembered now, I forgot to hold the gas pedal at WOT while cranking the engine. Hmm. I'll redo it tomorrow and see if the numbers change.
Reply
Old Jun 11, 2009 | 03:01 AM
  #7  
Targa250R's Avatar
be professional
 
Joined: Oct 2002
Posts: 14,842
Likes: 13
From: Pittsburgh, PA
Default Re: Compression Test

It doesn't matter. It's fine. You're reading way too much into this.
Reply
Old Jun 11, 2009 | 08:08 AM
  #8  
civic_driver's Avatar
Thread Starter
Honda-Tech Member
 
Joined: Aug 2005
Posts: 2,582
Likes: 2
From: USA
Default Re: Compression Test

Yeah, I know. I just want to know what proper numbers I should be getting for this engine since I've never done a compression test before.

I'll redo it today just for kicks
Reply
Old Jun 11, 2009 | 10:47 AM
  #9  
Jimster480's Avatar
Honda-Tech Member
 
Joined: Aug 2008
Posts: 6,239
Likes: 2
From: Miami, FL, USA
Default Re: Compression Test

the numbers do seem a litlte high. But that is perfectly fine. you have to worry when they are low lol.
Reply
Old Jun 11, 2009 | 01:17 PM
  #10  
civic_driver's Avatar
Thread Starter
Honda-Tech Member
 
Joined: Aug 2005
Posts: 2,582
Likes: 2
From: USA
Default Re: Compression Test

Ok, so I did the test again. This time I held the gas pedal at WOT and my numbers are almost the same. Here they are: 195-192-197-199.

The problem I see is that people say, the exact numbers don't matter, what matters is that they are within 10% of each other. Well, my question then is, if the numbers you get from different compression gauges are different then how do you know if it's time to change/rebuild the engine (i.e. when one or more of the cylinders drop below 135psi as is the case for 96-00 d-series engines)?
Reply
Old Jun 11, 2009 | 01:18 PM
  #11  
Sr420Det's Avatar
Honda-Tech Member
 
Joined: Aug 2006
Posts: 1,780
Likes: 0
From: Wilmington, NC
Default Re: Compression Test

Those numbers seem pretty sound to me. Why are you doing a compression test is it running like **** or something? Dont know seems one of those gauges is off
Reply
Old Jun 11, 2009 | 01:19 PM
  #12  
civic_driver's Avatar
Thread Starter
Honda-Tech Member
 
Joined: Aug 2005
Posts: 2,582
Likes: 2
From: USA
Default Re: Compression Test

Originally Posted by Jimster480
the numbers do seem a litlte high. But that is perfectly fine. you have to worry when they are low lol.
Exactly, that's my question, how do you know when they're low enough to require engine replacement/rebuilding with any particular compression gauge.
Reply
Old Jun 11, 2009 | 01:21 PM
  #13  
civic_driver's Avatar
Thread Starter
Honda-Tech Member
 
Joined: Aug 2005
Posts: 2,582
Likes: 2
From: USA
Default Re: Compression Test

Originally Posted by Sr420Det
Those numbers seem pretty sound to me. Why are you doing a compression test is it running like **** or something? Dont know seems one of those gauges is off
No, it's running great. I just did a valve adjustment and changed the spark plugs which were long overdue and it's running like new. I bought a compression gauge recently and wanted to see what the numbers are on a "healthy" engine so that I know when it's time to rebuild the engine (plus it's my first time doing a compression test, I just wanted to do it )
Reply
Old Jun 11, 2009 | 01:43 PM
  #14  
Jimster480's Avatar
Honda-Tech Member
 
Joined: Aug 2008
Posts: 6,239
Likes: 2
From: Miami, FL, USA
Default Re: Compression Test

Originally Posted by civic_driver
No, it's running great. I just did a valve adjustment and changed the spark plugs which were long overdue and it's running like new. I bought a compression gauge recently and wanted to see what the numbers are on a "healthy" engine so that I know when it's time to rebuild the engine (plus it's my first time doing a compression test, I just wanted to do it )
if its below like 120 on a stock motor there is a serious problem. But it varies per motor since different motors have different compression ratios. So they would have higher PSI from the beginning
Reply
Old Jun 11, 2009 | 02:09 PM
  #15  
Targa250R's Avatar
be professional
 
Joined: Oct 2002
Posts: 14,842
Likes: 13
From: Pittsburgh, PA
Default Re: Compression Test

When the engine is bad, you'll know it. Trust me.

A D16Y7 won't due of gradually lowering compression. If anything, it will die of head gasket failure or catastrophic oiling issues.
Reply
Old Jun 11, 2009 | 02:27 PM
  #16  
Jimster480's Avatar
Honda-Tech Member
 
Joined: Aug 2008
Posts: 6,239
Likes: 2
From: Miami, FL, USA
Default Re: Compression Test

Originally Posted by Targa250R
When the engine is bad, you'll know it. Trust me.

A D16Y7 won't due of gradually lowering compression. If anything, it will die of head gasket failure or catastrophic oiling issues.
nah it can. My original Y8 was beat to ****. I never compression tested it but I know it was low. I got beat by stock DX's and ****, and I couldnt even hit 100 in it until i got a P2P and even then i could barely get to 105. But it didnt burn oil or spin a bearing, it was all stock it just sucked major dick lol.
Reply
Old Jun 11, 2009 | 03:05 PM
  #17  
civic_driver's Avatar
Thread Starter
Honda-Tech Member
 
Joined: Aug 2005
Posts: 2,582
Likes: 2
From: USA
Default Re: Compression Test

A headgasket failure would be much easier to fix. I hope it lasts at least until it hits 150K miles. Anything more is bonus.
Reply
Old Jun 11, 2009 | 04:41 PM
  #18  
Jimster480's Avatar
Honda-Tech Member
 
Joined: Aug 2008
Posts: 6,239
Likes: 2
From: Miami, FL, USA
Default Re: Compression Test

Originally Posted by civic_driver
A headgasket failure would be much easier to fix. I hope it lasts at least until it hits 150K miles. Anything more is bonus.
mine had like 150k on it when i bought it.
Reply
Old Jun 11, 2009 | 07:10 PM
  #19  
Targa250R's Avatar
be professional
 
Joined: Oct 2002
Posts: 14,842
Likes: 13
From: Pittsburgh, PA
Default Re: Compression Test

Originally Posted by civic_driver
A headgasket failure would be much easier to fix.
Not with higher mileage. If you freshen the head on a worn bottom end, it's going to burn oil like nobody's business. Once the head gasket goes, you might as well tear it down completely to at least re-ring it and hone the cylinders.
Reply
Old Jun 11, 2009 | 11:06 PM
  #20  
jluo_hatchy's Avatar
Junior Member
 
Joined: Feb 2009
Posts: 20
Likes: 0
Default Re: Compression Test

sounds fine to me. nthing to worry about
Reply
Old Jun 11, 2009 | 11:42 PM
  #21  
likwid2u's Avatar
Honda-Tech Member
 
Joined: May 2007
Posts: 167
Likes: 0
From: ontario, ca, us
Default Re: Compression Test

Originally Posted by Jimster480
if its below like 120 on a stock motor there is a serious problem. But it varies per motor since different motors have different compression ratios. So they would have higher PSI from the beginning
when i worked at c&t japanese engines if the motor was under 150 on compression the motor would smoke customers would come back and complain
Reply
Old Jun 12, 2009 | 06:32 AM
  #22  
Jimster480's Avatar
Honda-Tech Member
 
Joined: Aug 2008
Posts: 6,239
Likes: 2
From: Miami, FL, USA
Default Re: Compression Test

Originally Posted by Targa250R
Not with higher mileage. If you freshen the head on a worn bottom end, it's going to burn oil like nobody's business. Once the head gasket goes, you might as well tear it down completely to at least re-ring it and hone the cylinders.
wtf are you talking about? A worn bottom end? If you dont overheat your **** then it wont be warped and the bottom end wont be "worn" so you can replace the gasket and its all good. My friend just replaced the gaskets on a motor that had 200k, it doesnt burn oil for **** so dunno what your talkin about.
Reply
Old Jun 12, 2009 | 06:58 AM
  #23  
Targa250R's Avatar
be professional
 
Joined: Oct 2002
Posts: 14,842
Likes: 13
From: Pittsburgh, PA
Default Re: Compression Test

Originally Posted by Jimster480
wtf are you talking about? A worn bottom end? If you dont overheat your **** then it wont be warped and the bottom end wont be "worn" so you can replace the gasket and its all good. My friend just replaced the gaskets on a motor that had 200k, it doesnt burn oil for **** so dunno what your talkin about.
Okay . . .

Everything obviously went over your head.

That's fine. Once you get a little bit older than 18 and get some experience under your belt, you'll see what I mean.
Reply
Old Jun 12, 2009 | 07:55 AM
  #24  
Jimster480's Avatar
Honda-Tech Member
 
Joined: Aug 2008
Posts: 6,239
Likes: 2
From: Miami, FL, USA
Default Re: Compression Test

Originally Posted by Targa250R
Okay . . .

Everything obviously went over your head.

That's fine. Once you get a little bit older than 18 and get some experience under your belt, you'll see what I mean.
i already have plenty of experience, thanks.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
76 camaro car
Honda Accord (1990 - 2002)
2
Apr 20, 2017 04:47 AM
92vxjdm
Tech / Misc
1
Aug 15, 2008 05:05 AM
snowblind7x
Honda Prelude
12
Apr 13, 2005 08:12 PM
MechEng
Honda Prelude
10
Feb 11, 2002 06:15 PM




All times are GMT -8. The time now is 08:51 PM.