There is an S70 near me that the owner says has a blown head gasket. They say it smokes real bad out of the tail pipe and in the engine compartment. I was thinking about getting it and fixing it up for my sister.

What causes a head gasket to blow and is it a tough job to correct?

I just did my 1st timing belt job on my 960 and thought it was kinda easy. I have also done a few PCV system replacements and did not find that difficult, just time consuming. Don't want to get a donor car but rather something I can fix for under $300.

 

Hard to say what the cause is, most of the time it's overheating. I did the head on my car, and I have one suggestion, make damn sure you have and impact wrench. All my bolts were seized and all I had was leverage. I broke a whole pile of tools on that job. The technical aspect of it wasn't too bad, but everything was insanely tight and threadlocked together. If the headgasket is really blown you'll need to check the head and make sure it's not screwed up. My machine shop bill was 4 or 5 hundred dollars, but i had some bent valves.
It's kind of a cool experience though, and everything is mega easy to change once the head is off.

To verify if its a head gasket you'll want to look at the color of the smoke, examine the oil for a milky appearance and do a compression check. I think tolerance is within 20 percent of spec, but don't quote me.

 

Normally like Paulie said, it's caused by overheating...... The gasket it self isn't an expensive thing to get as most of the time you are being charged 12 hours of book labor. It can be done, but it is labor intensive.

 

So, it the source problem is overheating, then it's a bad water pump or t-stat? What else could cause that? They claimed they did not let it overheat. "Once it started smoking we turned it off on the side of the road..."

 

If it started smoking, den it. def too late! The fact was the coolant got so hot it started to smoke..... See my point, they just had no clue... Its usually a bad thermostat and/or water pump.. I would def. replace those along with the head gasket and other "maintenance" items of you bought it, to cover your basis...... Also if changing out the thermostat and water pump, make sure to do the temp sensor.... Good Luck!

 

Check to see if there's coolant in the oil. Yes? head gasket is definitely bad. No? see if it's "burning" coolant- fill the coolant up all the way, and see if there's clouds of sweet- smelling white smoke/ steam coming out of the exhaust. Yes? head gasket or head.

If you get the car, when you take the head off, make sure to have a machine shop check it for cracks and warpage- this is one job you don't want to do, only to need to do it again! As for using an impact wrench on the head bolts, that's not really a good idea, as you need to back them off in reverse order of the tightening sequence 1/4 turn at a time. Use a very good quality thin- walled (because of the holes) 14mm 6- point socket- 1/2" drive- and a BIG breaker bar to get the head bolts loose.

And yes, this is a time- consuming job- like Somthngfrce said- Book says 12 hours labor, and that assumes you have Volvo's special tools, which save time. While you're in there, be sure and replace the timing belt, all 4 cam seals, PCV system, water pump, timing belt idler, and tensioner pulleys

 

comparing doing a PCV or a timing belt is irrelevant as a skill set to do a head replacement.

Get a reconditioned head complete, from a place in Clearwater that will have it in stock. Exchange core and so on. It cost like $400 with new valves.

Search

 

http://www.cylinder-heads.com/

 

Cool. Thanks for the input. My goal is to be into a car for $1,500 or less. I know that is a streatch but possible. I wouldn't mind putting a lot of labor into a car but I just don't have a lot of cash to toss at my sisters situation at the moment.

It sounds like getting a car with a blown head gasket may not be a smart thing for me to do. I would do better finding a beatter around here somewhere that I can service and give to her. I'll let you guys know what I end up doing.

 

Carrots - You're a bad man dude! You must own some serious tools too! I did my head that way, and I broke a pile of craftsman tools, chinese junk, and even some snap(ped)-on that filled a grocery bag. That job was a doozy. I have a friend that's still mad at me for getting his help - lol

 

It helps if you're not AKA "Slep Rock".

 

"slep Rock" I don't understand.