I lose compression w/ valve adjust - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 11-22-2009, 08:33 PM
Registered User
 
Join Date: Nov 2009
Location: Palm springs
Posts: 3
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
I lose compression w/ valve adjust

Ok so I am I am so lost I don't even know where to start. Lets start with what I have
sbc 350
speedpro 12 to 1 .040 over pistons
stock length rods
cloyes tru roller timing chain set that I installed on the 0 marks
edelbrock performer plus cam (duration at .050.. 204 intake 214 exhaust) (Lift 420 intake 442 exhaust)
edelbrock performer rpm heads (2.02 intake 1.60 exhaust 64cc)

I installed everything correctly and did the valves the proper way..... exhaust starts, intake, intake up and fully closed, exhaust.... 0 lash + 1/2 turn)

did timing right

installed and did not start... pulled plugs and it feels like no compression (pulls finged in and does not blow it back off) so i backed all the rocker arms off and it has compression (blows my finger off) redo valves and same thing, redo to 0 lash and still the same thing (and I have tried using different adjusting methods). PLEASE HELP

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 11-22-2009, 08:41 PM
Zimmo's Avatar
Member
 
Last photo:
Join Date: Sep 2004
Location: Ex So-Cal, now in CT
Age: 47
Posts: 158
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
If you are adjusting hyd lifters, they will hyd lock & cause the valves to stay open. About the only thing you can do is to let them sit overnight to allow them to bleed off some pressure.
Was this engine previously run, or were the lifters submerged in oil?
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 11-22-2009, 09:07 PM
Registered User
 
Join Date: Nov 2009
Location: Palm springs
Posts: 3
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
not submerged... never ran
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 11-22-2009, 09:20 PM
Zimmo's Avatar
Member
 
Last photo:
Join Date: Sep 2004
Location: Ex So-Cal, now in CT
Age: 47
Posts: 158
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Did anyone pre-fill & pump up the lifters by hand before installing them?
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 11-22-2009, 10:01 PM
F-BIRD'88's Avatar
Yada Yada Yada
 
Last photo:
Join Date: Oct 2005
Location: Ontario, Canada
Posts: 9,550
Wiki Edits: 0

Thanks: 3
Thanked 334 Times in 331 Posts
Instead of spinning the push rod in your fingers to sense the o lash point, move the rocker up and down, up and down. Stop tightening as soon as the push rod no longer goes up and down in your fingers.

Then with all the plugs removed turn the motor over by hand checking each cylinder spark plug hole for compression using your finger over the spark plug hole as you progress thru the firing order. Each cylinder will come up on compression stroke very 45deg thru the fireing order as you spin the crank.

Fire it up and then set the lifters/rockers while its running.

If you check for the o lash point by spinning the pushrod in your fingers till it stops, you end up going to to far. Up - down works better.

Compression ratio is a bit high, isn't it?

Last edited by F-BIRD'88; 11-22-2009 at 10:09 PM.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 11-23-2009, 07:45 AM
Registered User
 
Join Date: Nov 2009
Location: Palm springs
Posts: 3
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
no i didnt pump up the lifters the first time. and the up and down method is what I always use. yes it is alot of compression but this motor is in an off road race truck that I run race gas in. and now i am wishing i would have not gone so big with the dome. I am so frustrated with this at this point, I am ready to give up.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 11-23-2009, 09:29 AM
airboat's Avatar
Registered User
 
Last photo:
Join Date: Mar 2006
Location: Canada
Posts: 286
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
If all else fails use this procedure. I think the manufacturers are using a longer ramp on some of the new cams. all I know is I got bit after never having a problem for 35 years?
http://www.centuryperformance.com/ad...h-spg-149.html

Valve Adjustment Procedure - The Quick and Accurate Way:
First, view this little chart below for Small and Big Block Chevy Engines that I made and see if you can understand it. There is more of an explanation below the chart. For other engines you will use the firing order that matches your engine to create a similar chart. This chart is based upon "opposite" cylinders of your firing order. (see below)
Intake Valve Adjustment: ENGINE OFF!
with #1 cylinder Intake Valve at full valve lift .... Adjust #6 Intake Valve
with #8 cylinder Intake Valve at full valve lift .... Adjust #5 Intake Valve
with #4 cylinder Intake Valve at full valve lift .... Adjust #7 Intake Valve
with #3 cylinder Intake Valve at full valve lift .... Adjust #2 Intake Valve
with #6 cylinder Intake Valve at full valve lift .... Adjust #1 Intake Valve
with #5 cylinder Intake Valve at full valve lift .... Adjust #8 Intake Valve
with #7 cylinder Intake Valve at full valve lift .... Adjust #4 Intake Valve
with #2 cylinder Intake Valve at full valve lift .... Adjust #3 Intake Valve
Exhaust Valve Adjustment: ENGINE OFF!
You will notice that this is the same procedure and sequence as the intake valves listed above. Only now you are adjusting ONLY the exhaust valves the same way.
with #1 cylinder Exhaust Valve at full valve lift .... Adjust #6 Exhaust Valve
with #8 cylinder Exhaust Valve at full valve lift .... Adjust #5 Exhaust Valve
with #4 cylinder Exhaust Valve at full valve lift .... Adjust #7 Exhaust Valve
with #3 cylinder Exhaust Valve at full valve lift .... Adjust #2 Exhaust Valve
with #6 cylinder Exhaust Valve at full valve lift .... Adjust #1 Exhaust Valve
with #5 cylinder Exhaust Valve at full valve lift .... Adjust #8 Exhaust Valve
with #7 cylinder Exhaust Valve at full valve lift .... Adjust #4 Exhaust Valve
with #2 cylinder Exhaust Valve at full valve lift .... Adjust #3 Exhaust Valve

--------------------------------------------------------------------------------

Now I'll Provide an Explanation:



What you see above is adjustments being made on "opposite" valves on the engine cycle. The small and big block Chevy engines use a firing order of 1-8-4-3-6-5-7-2. What you do is separate the order into the two sides of the firing order. These are "exact" opposites that put the opposing valve at the correct location for adjustment, meaning the back side (base circle, or heal) of the cam lobe (see image at left).

Looking at the chart below you will see that #1 is opposite #6, and vice-verse, on through the firing order. This holds true for both intake and exhaust valves.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may 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


Similar Threads
Thread Thread Starter Forum Replies Last Post
olds #5 head johann Engine 1 07-30-2006 10:05 PM
valve adjustment 383 stroker solid lifter cam 73luvdrag Engine 4 05-15-2004 03:01 AM
Please HELP valve adjust? 1985fiero Engine 10 05-03-2004 06:50 PM
big block chevy valve adjustment trouble,no compression dufrain Engine 11 09-28-2003 08:07 AM
Cam Help black66 Engine 3 05-12-2003 06:15 PM


All times are GMT -6. The time now is 04:26 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.