#1 (permalink)  
Old 05-31-2008, 02:17 PM
SonomaSpider's Avatar
SonomaSpider SonomaSpider is offline
Registered User
 
Join Date: Jul 2007
Location: Sonoma County, California
Posts: 13
Blown Head Gasket

I'm trying to resurrect my 77 Spider after 9 idle years, during which it was rarely started and never run on the road. I had suspected the head gasket was on the way out (for the 3rd time) but after looking again found an air leak in the fuel pickup - which I fixed. Then I rebuilt the seized brake calipers, replaced the brake master cylinder and rebuilt the clutch master. I also replaced the brake hoses (but forgot the clutch hose, which of course failed)

So its running again and even passed the emissions test for smog, failing only a visual because of a missing gasket in the fuel cap - Sheesh! After a quick trip to the hardware store to fix THAT problem I was on my way back to the smog test station to give them ANOTHER $70 when the head gasket did in fact finally blow.... depressing

After failing to seal it the first 2 times, the head was inspected and completely rebuilt by Alfa Parts in Berkley, where it was pronounced to be in perfect condition, not requiring any machining or straightening. We went over the proper torque procedure and I believe I did it correctly. But I didn't think it sealed properly and now it is definitely leaking into the water jacket at cylinder #1 (front of engine), as demonstrated by a leak down test which was blowing coolant out of the thermostat opening. The thermostat checked out fine BTW.

So what is my most likely problem? I seem to remember I had this suspicion that the cylinder liners may have been slightly depressed below the block. Is that possible / likely? I see that there is supposed to be a liner seal at the bottom of the liner. Can that affect the liner vertical position or does the liner sit on a metal lip?

This all started with a single overheating event a long time ago and apparently I have never gotten the head to seal properly since. I know there is a wealth of experience here on this board and I'm hoping someone can either help me puzzle this out or point me to a thread that covers this issue.

Thanks!
-Colin
__________________
77 Alfa Spider Since 1988 - non-op since 1999
87 Celica GTS ; Previous 74 Lancia Beta Coupe
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #2 (permalink)  
Old 05-31-2008, 08:06 PM
SonomaSpider's Avatar
SonomaSpider SonomaSpider is offline
Registered User
 
Join Date: Jul 2007
Location: Sonoma County, California
Posts: 13
Hmmm.
The Engine Rebuilding forum seems to have a fair amount of information on Liners etc. Duh!
It seems that the Liner seals (O-rings) do NOT set the height, so if I am low, its because the liners would have to be short, with little or no chance of adjusting. That doesn't seem so likely.
Looks like I have to pull the head off again and this time pay close attention to the entire procedure.
I was looking at my notes from '97 when I did this and the instructions I got from Alfa Parts was to torque to spec cold, then re-torque warm at +5ft-lbs more than cold. I'm sure I would have done this given that it was my third time and I didn't want there to be a fourth....

-Colin
__________________
77 Alfa Spider Since 1988 - non-op since 1999
87 Celica GTS ; Previous 74 Lancia Beta Coupe
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #3 (permalink)  
Old 05-31-2008, 09:05 PM
Tifosi's Avatar
Tifosi Tifosi is online now
Slacker
Platinum Subscriber
 
Join Date: Mar 2006
Location: Northern NY, USA
Posts: 6,308
When you're poking around down in the engine rebuilding section, search up keyword 'liner protrusion' which should bring you many results on the process and why-for of it all.

The basic idea is that the liners should be above the deck surface of the block by a specific amount prior to gasket and head install, and torquing the head down makes it a squished tight seal/fit.
__________________
Darren
'84 manufacture ~ '85 MY Spider Graduate
ghnl's '82-'89/Series 3 Spider L-jet diagnostic page
as hosted by
Greg Gordon's highperformancestore
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #4 (permalink)  
Old 06-01-2008, 07:15 AM
alfaparticle's Avatar
alfaparticle alfaparticle is offline
Senior Member
Platinum Subscriber
 
Join Date: Oct 2004
Location: Columbia SC
Posts: 1,281
The threads on the studs and nuts must be clean and lubricated. The faces of the nuts and washers should be smooth and lubricated. Otherwise You can get false torque indications. I clean the threads with a tap and die. You might also get your torque wrench checked.
__________________
Ed Prytherch
79 Spider Veloce
88 Milano Verde
88 Milano Verde
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #5 (permalink)  
Old 06-01-2008, 07:31 AM
DarkWolf40's Avatar
DarkWolf40 DarkWolf40 is offline
Registered User
 
Join Date: Mar 2008
Posts: 64
You know thats a good idea about the torque wrench. Where I work its a major problem. Not only do many torque wrenches not torque to the value you've dialed in but many people don't know how to properly use them. Drop a torque wrench once and its probably going to be off.
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #6 (permalink)  
Old 06-01-2008, 09:35 AM
SonomaSpider's Avatar
SonomaSpider SonomaSpider is offline
Registered User
 
Join Date: Jul 2007
Location: Sonoma County, California
Posts: 13
I replaced my old (old) Harbour Freight torque wrench last year with another HF special. I cant say if the original one was reasonably calibrated at the time, but a few years back I did check it and adjusted it a little.
I did try to re-torque yesterday and buffed the washers on a wire wheel, then cleaned and lightly oiled the stud threads and washer. All nuts went down smoothly to the end by hand and then required ~ 1/2 turn to click at 58ft-lbs. No change in the leak down, so its a lost cause. Its also possible that sitting 9 years with mostly water as a coolant (ouch) caused internal corrosion.
I remember the studs looked very corroded the last time I did the head gasket, so I was afraid of shearing one of them. Having read the engine forum on whats involved to extract one, I'm even more afraid now!
__________________
77 Alfa Spider Since 1988 - non-op since 1999
87 Celica GTS ; Previous 74 Lancia Beta Coupe
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
  #7 (permalink)  
Old 06-01-2008, 02:59 PM
alfaparticle's Avatar
alfaparticle alfaparticle is offline
Senior Member
Platinum Subscriber
 
Join Date: Oct 2004
Location: Columbia SC
Posts: 1,281
I aquired an engine that had sat for a long time without antifreeze and the head was stuck to the studs. I broke the head trying to get it off. The studs did not break. If you were able to get the head off then you should be ok.
__________________
Ed Prytherch
79 Spider Veloce
88 Milano Verde
88 Milano Verde
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiFurl this Post!
Reply With Quote
Reply

Thread Tools
Display Modes

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 Off
Pingbacks are Off
Refbacks are Off



AlfaBB Blog Articles

Advertisement


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2008, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO 3.0.0
Copyright 2002-2008 AlfaBB.com All Rights Reserved.


An exclusive design by: Forumskin.com