Cracked Head or Blown Gasket? - Hot Rod Forum : Hotrodders Bulletin Board -- 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
lost password?   |   register now

LinkBack Thread Tools
  #1 (permalink)  
Old 12-15-2004, 09:55 PM
Registered User
Last photo:
Join Date: Dec 2004
Location: Tulsa
Posts: 2
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Cracked Head or Blown Gasket?

My '71 Olds Rocket 350 seems to either have a blown head gasket, cracked head or worse a cracked block. By reading many past posts I understand that a compression test is not the best method for testing these problems. My motor starts and runs good but as it warms up it starts missing getting worse the more it warms up. Until it wont idle at all. But if you give it some gas it will keep running. The other night after keeping it running for about 10 or 15 minutes until it starting missing worse than ever, I decided to do a compression check. Keep in mind this was the worst its ever missed . Any way on the #4 and #6 no compression at all. So I know somethings wrong big time. But the funny thing is that after letting engine cool down the compression goes back to normal, its even a little higher than any other cylinders for #4. Well I know I'v got something wrong in this area, but wonder if I should try some K&W block seal before pulling the head off. Will this help me to determine which problem, Blown gasket, cracked head or cracked block. I just want to get to the root of the problem this time, I pulled the head off before and could see no visible problems. Now its become much worse. Sense it gets worse as engine warms leads me to believe its a crack. But Im pretty much a newbie at all this and may be overlooking some other approach one of you may have. Oh and I get white smoke out of exhaust on start up but goes away after a few minutes. Lots of bubbling while engine is running in radiator.

Today started up and let run until warm. This time it didnt miss as bad as last time but was still bad miss. Did another compression check and all ok this time only # 4 higher than the rest.
I plan to pull head and take to machine shop to have check over But I am wondering should I do block sealer before this?

sick Olds Rocked 350

Reply With Quote Quick reply to this message
Sponsored Links
  #2 (permalink)  
Old 12-15-2004, 10:08 PM
New Member
Last photo:
Join Date: Dec 2004
Location: Williston,Fl
Age: 56
Posts: 24
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
cracked head or block

The bubbles are coming from the cracks in your block or heads.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply

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:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Please select your insurance company (Optional)


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

All times are GMT -6. The time now is 02:00 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999 - 2012. All Rights Reserved.