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What does compressed volume mean with head gaskets (little long winded)

  • Thread starter Thread starter TheBocSez
  • Start date Start date Jun 25, 2006

TheBocSez

New Member
Feb 3, 2004
652
0
0
Converse, TX
Jun 25, 2006
#1
  • Jun 25, 2006
  • #1
I think I have a blown head gasket. I have been in denial but I am pretty sure now. I am going to buy one of those hydrocarbon test kits and if it shows positive then I will be sure.

I am looking at the Felpro Permatorque MLS gaskets.
http://www.jegs.com/webapp/wcs/stor...Id=10002&categoryId=29251&searchItemId=348909

It says compressed thickness is .041 and compressed volume is 14.9cc.

Thats higher than the others, so what is compressed volume and how or will it affect my compression ratio. I am only at about 9.0:1 or so so I dont want it to drop any lower.

Im sure someone will ask why I think I have a blown head gasket so I might as well cover it now.

I had an overheating problem and replaced all of my cooling components. The problem seems to be pretty much under control but the temp will climb if I get on it.

My overflow bottle is always full and this morning, I noticed a small puddle under the car. I started the car and checked the overflow and noticed that it was purculating mildly. I also noticed that when the car heated up to operating temp, that it stopped. So I think its a small leak that seals itself at operating temp....for now.

After driving the car for a while, I also noticed that when I park the the overflow pukes a little (maybe about 1/3 cup or so)

I did a compression test and my results were (warm)

#5 = 150
#6/7/8 = 145
#4/3/2/1 = 135-137 range.

I made a few mistake when taking the comression readings in that I didnt prop the throttle blade open or stop fuel flow, so there is the possiblity that the time delay and fuel flow cooled the 1-4 cyl and cause the slightly lower reading.

I dont have a leak down tester to use. I can rent one of the cooling system pressure testers, and I think that the hydrocabon test kit is the definitive answer for head gaskets.

I figure that if I have to replace one, I might as well replace both. I mean its not that much more work.

So, now that I am way off topic.. what does compressed volume mean?
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Jun 26, 2006
#2
  • Jun 26, 2006
  • #2
A thicker gasket will decrease the CR.

I have a calculator on my website if you want to see how much. (it is in excel)
I doubt it will be significant though.
I wouldn't even worry about it

jason
 
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