Blown Head Gasket?
Thread Starter
Racer
Joined: Mar 2005
Posts: 370
Likes: 1
From: Webster, NY USA
Blown Head Gasket?
What else can go wrong? If any of you have followed my progress of getting the '79, 5 Speed back on the road you know it has not been easy. I think I may now have a fatal problem...blown head gasket.
The car came to me with a seized water pump which the PO thought was only a coolant leak, so the car has a history of overheating. I have no idea how long the car was run in this condition or how hot it got. When I got the car it had NO coolant in the overflow tank.
Now when I start the engine from cold and after about 15-30 sec I get a great volume of white vapor (not smoke) from the exhaust. At first I thought it was the normal burnoff of condensation, but this is just too much and lasts too long. However, after about a minute the vapor is gone and does not return until after the enging has been shut down and cooled. The car runs OK otherwise and the plugs look OK and the compression test showed 135 to 150 psi. I did not do a leak down test.
So my conclusion now is that I have a blown head gasket or some other leak of coolant into the combustion chamber/s.
Is there anything else it could be?
Can the heads be removed without removing the engine?
What else can I do the pin down the problem?
What are my options?
The car came to me with a seized water pump which the PO thought was only a coolant leak, so the car has a history of overheating. I have no idea how long the car was run in this condition or how hot it got. When I got the car it had NO coolant in the overflow tank.
Now when I start the engine from cold and after about 15-30 sec I get a great volume of white vapor (not smoke) from the exhaust. At first I thought it was the normal burnoff of condensation, but this is just too much and lasts too long. However, after about a minute the vapor is gone and does not return until after the enging has been shut down and cooled. The car runs OK otherwise and the plugs look OK and the compression test showed 135 to 150 psi. I did not do a leak down test.
So my conclusion now is that I have a blown head gasket or some other leak of coolant into the combustion chamber/s.
Is there anything else it could be?
Can the heads be removed without removing the engine?
What else can I do the pin down the problem?
What are my options?
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Joined: Nov 2001
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From: Endwell, New York
What you are describing is the classic sign of a blown head gasket. This type of failure allows coolant to get into the cylinder. When the car is started (if it will even start) it will run very rough at first until the coolant clears the cylinder then when the wet cylinder(s) actually fire up huge clouds of steam will exit out the exhaust pipe. Now, if the engine runs long enough to where the coolant is hot and pressurized and the engine is then shut down, the pressurized coolant will squirt into the cylinder(s) possibly filling them. If the particular cylinder(s) that are filled with coolant are entering their compression stroke and an attempt is made to start the engine again, there is a good possibility that it will hydro-lock. The piston will be trying to compress a liquid (impossible) and you may damage some internal parts (starter, rods, etc..). I'd recommend not starting the engine anymore and start planning for a head removal. Based on the questionable history of the engine you probably want to do both heads. I've heard of people removing the heads on the studded engines but that sounds to me like a lot more aggravation than it's worth. Good luck!
Burning Brakes
Joined: Oct 2004
Posts: 877
Likes: 1
From: Suburban St. Louis in Illinois.
Not too sure about the 928 motor...but this could also be indicative of a cracked intake manifold/leaking intake gasket as well..if I recall correctly, on my car the coolant passage that supplies the heater vacuum valve is very near the intake port on the right rear of the motor...and the themostat to cylinder head crossover manifold has potential to leak into an intake port without necessarily indicating a blown head gasket...do the leakdown test for definitive answers...good luck. 
Drifting
Joined: May 2001
Posts: 2,747
Likes: 3
From: Owasso, OK
The heads can be removed without removing the engine. The biggest obstacle is getting the exhaust manifold moved to allow the heads to move up the studs. I was able to accomplish it be removing the exhaust studs using the double nut technique. It's tight but can be done.
Recommend a leakdown test to confirm it is a head gasket.
Dennis
Recommend a leakdown test to confirm it is a head gasket.
Dennis
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From: AZ
Originally Posted by AJK
Can the heads be removed without removing the engine?
What are my options?
Besides, with the engine out is a good chance to reseal the engine and fix all those small things that are SO MUCH easier to get at.
We had a choice?
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From: Texas
A couple of things you can do quickly. Pull the plugs, the one(s) with coolant will be burning at a dfferent temp. I was able to see coolant in my #7 cylinder at BDC with a small maglight. Turn the engine clockwise at the crank bolt with a 27mm socket IIRC. Your oil strainer will have condensation on/in it. So will your breather hoses internally. I am doubtfull that there will be condensation on your dip stick (never was with mine.) Do the compression check and other diagnostics to confirm too. If it is a head gasket, it can be done in the car. However, it is actually better to pull the engine, IMHO. Engine mounts and other routine maintenence items can be done at the same time. If your car is has been overheating or a history of overheating, have your heads checked for warping, cracks and electrolysis. Don't just put a new head gasket on and assume you've fixed it. I know you want it back on the road ASAP, but if you take the time to fix it right and attend to the other things YOU WILL find, it will be on the road much longer. I changed my head gasket on cylinders 5-8 3 times due to a migrating cylinder sleeve in #7. BTDT
USMarine
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From: Brush Prairie, Washington
Originally Posted by AJK
Can the heads be removed without removing the engine?
MAJOR PITA!!! Take the engine out. Bob Voytchef has done this without removing the engine but I have never personally shaken the hand of anybody else that has.
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Thread Starter
Racer
Joined: Mar 2005
Posts: 370
Likes: 1
From: Webster, NY USA
Thank you all for the prompt reply. Not good news, but confirms what I thought.
If this turns out to be the case from further testing, I will probably not keep the car. I can't do this job myself and the cost to have it done far outweighs the resulting value of the fixed car. Do any of you have suggestions for disposing of it?
Thanks again.
If this turns out to be the case from further testing, I will probably not keep the car. I can't do this job myself and the cost to have it done far outweighs the resulting value of the fixed car. Do any of you have suggestions for disposing of it?
Thanks again.
928 OB-Wan
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Joined: Apr 2004
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From: Zebulon, NC
Originally Posted by AJK
Thank you all for the prompt reply. Not good news, but confirms what I thought.
If this turns out to be the case from further testing, I will probably not keep the car. I can't do this job myself and the cost to have it done far outweighs the resulting value of the fixed car. Do any of you have suggestions for disposing of it?
Thanks again.
If this turns out to be the case from further testing, I will probably not keep the car. I can't do this job myself and the cost to have it done far outweighs the resulting value of the fixed car. Do any of you have suggestions for disposing of it?
Thanks again.
I have a set of freshly redone 79 Euro heads and a full engine gasket set
Nordschleife Master
Joined: Jul 2003
Posts: 7,743
Likes: 78
From: Minneapolis
Sounds like a head gasket. Do this simple test:
Start with car completely cool.
Pull the fuel pump relay
Remove all spark plugs
Have someone crank the engine while you watch.
If coolant flies out the plug holes, you'll know.
Pulling the engine would be the "smarter" way especially if you've got the time and $$$ do really get into other repairs. With $2k and a couple of months, you could rebuild the whole engine, replace the engine mounts and get to other repairs. Those hoses to the overflow tank and the clutch master come to mind.
Removing the heads in the car is doable. I rate that experience as the most aggrivating and miserable job I've done on my car. The bolts along the bottom of the cam tower are almost inaccessible and are likely frozen.
If going this way, I recommend pulling the head with the exhaust manifold attached. Just detach from the pipes and it'll come. It'll be heavier and awkward so maybe get a helper.
Start with car completely cool.
Pull the fuel pump relay
Remove all spark plugs
Have someone crank the engine while you watch.
If coolant flies out the plug holes, you'll know.
Pulling the engine would be the "smarter" way especially if you've got the time and $$$ do really get into other repairs. With $2k and a couple of months, you could rebuild the whole engine, replace the engine mounts and get to other repairs. Those hoses to the overflow tank and the clutch master come to mind.
Removing the heads in the car is doable. I rate that experience as the most aggrivating and miserable job I've done on my car. The bolts along the bottom of the cam tower are almost inaccessible and are likely frozen.
If going this way, I recommend pulling the head with the exhaust manifold attached. Just detach from the pipes and it'll come. It'll be heavier and awkward so maybe get a helper.
Rennlist Member
Joined: Feb 2003
Posts: 29,828
Likes: 218
From: saratoga, ca
yank the engine, if you work fast, you can have it on an engine stand in 4 hours! (back in in probably less.) you will spend 4 hours just scrapping the gasket material off the heads from the cam tower gaskets!! BTDT!
pull all the front stuff off the engine, p/s reservoir, spark box, radiator etc.
pull exhaust headers off, pull clutch out. remove engine mount bolts, yank engine. its that easy!
Im on my 3rd time in 3 months now! mostly with only metwrench and the mikita . dont forget the long 6mm allens, and the 27mm crank bolt socket with breaker bar.
MK
pull all the front stuff off the engine, p/s reservoir, spark box, radiator etc.
pull exhaust headers off, pull clutch out. remove engine mount bolts, yank engine. its that easy!
Im on my 3rd time in 3 months now! mostly with only metwrench and the mikita . dont forget the long 6mm allens, and the 27mm crank bolt socket with breaker bar.
MK
Drifting
Joined: Nov 2003
Posts: 2,763
Likes: 124
From: London, UK
This is with respect to an 87 not a 79:
Hemoving the heads in car is no fun. The most difficult part is undoing the bearing cap bolt right next to the front suspension strut. The heads will come out with the exhaust manifolds attached, can't see any point in separating them in situ, however they are pretty heavy when you're already knackered. The air injection plumbing is annoying when removing the heads, but you will probably not want to keep it when you put the heads back on. Finally, the gaskets aren't cheap, but worse still is the amount of WYAIT work you end up doing.
Hemoving the heads in car is no fun. The most difficult part is undoing the bearing cap bolt right next to the front suspension strut. The heads will come out with the exhaust manifolds attached, can't see any point in separating them in situ, however they are pretty heavy when you're already knackered. The air injection plumbing is annoying when removing the heads, but you will probably not want to keep it when you put the heads back on. Finally, the gaskets aren't cheap, but worse still is the amount of WYAIT work you end up doing.