96 850 headgasket

1volvoguy · Post by **1volvoguy** » 22 Oct 2014, 11:48

I have this nice clean solid 850 turbo. Bought it with a bad head gasket. Didn't appear to have over heated, and the previous owner said it didn't, just started skipping and dumping coolant. His story seems valid. Anyhow, the car now has about 156,000 miles. New head gasket, water pump, timing belt,etc. It runs well. I was going through a folder with maintenance records going back many years. I found that this car had a head gasket and head rebuild at 126,000 miles (5yrs ago). I also found the odometer had been repaired, indicating about a year with a failed odometer. I assume based on records I found that it probably has around 10,000 miles more than odometer says. All that being said, the head gasket repair lasted just 40,000+/- miles.
Anyone think I'm safe to assume this head gasket I replaced will go another 40k? Everything looked good, and I cleaned everything good before putting it all together. Just worries me that it didn't last so long??
Or are these 850 turbos just prone to this behavior? Thanks for any input!

Post by **erikv11** » 22 Oct 2014, 12:37

It is nothing peculiar to these engines, it is just a simple fact that the head never goes back on they way it did at the factory, almost no matter what shop did the job. A small imperfection on the head or block surface can mean a breached head gasket in 40k, it is not surprising. The head is not "just another job" for this reason, even though it may seem like it during the process. It is one where you need to be super careful, and not make big mistakes that show up right away or small mistakes that show up at 40k.

That is not at all to speak doom for your current repair though. A DIY mechanic may not be as skilled or experienced as a shop one, but the DIY can take the time to be more careful and deliberate on a head gasket repair. It is fair to assume the repair, done well, will last well beyond 40k.

Post by **rspi** » 22 Oct 2014, 15:32

Our S70 had a bad head gasket job that lasted about 40,000 miles I guess. I replaced it 28 months ago (20,000 miles) and it is still going strong.

1volvoguy · Post by **1volvoguy** » 22 Oct 2014, 22:50

I'm not new to engine work, I am a trained diesel tech. Worked in the heavy duty diesel field for 20 years. I am confident in my work. Just wasn't sure if I should be so confident in the car. This is our 2nd volvo car ever. 1st one was a 850 GLT, non-turbo. Ran awesome. That car lead me into the one I have now. I just don't know much about these. I don't even know anyone else that has had an 850. So when I ran across an invoice showing a head gasket job only 40K miles back, it got me a bit worried. Thinking maybe I got a car with a chronic issue or something? But maybe not. Other people I talked to said some turbo cars are a little tough on head gaskets due to higher compression and HP. I'm use to working on 700-860 cubic inc diesels. These are a bit new to me as far as how tough they are, or are not.lol
So it sounds like I didn't get a time bomb. I'm good with that! Thanks

Post by **erikv11** » 22 Oct 2014, 23:03

Aha, I see. Sounds like the best of both worlds, a tech who takes the time to do his own cars up with confidence. That engine is no time bomb at all, as long as you don't go crazy overboosting the internals are more than tough enough. Enjoy the car!

Post by **Ozark Lee** » 22 Oct 2014, 23:56

While I am guilty of divulging every single fault and every bad thing in a car's history when I sell it most sellers aren't so inclined. Either the PO didn't know that it overheated or they simply fibbed about it.

I would wager that 99% of Volvo whiteblock head gasket failures can be traced to coolant loss that results in overheating. If there was significant coolant loss before the engine got up to temp the gauge may have never properly registered if it had no coolant flow around the temp sensor.

...Lee

Post by **rspi** » 23 Oct 2014, 01:07

I understand what Lee is saying. On our bad head job the car slowly started loosing coolant through the expansion reservoir. Went from loosing 8 oz per month to 8 oz in 2 days over a 18 month spread. Then finally a road trip caused it to loose enough coolant to overheat the thing. Pushed all the coolant out of the bottle and the needle finally started to raise. That was my first head gasket job ever. Couldn't find a mechanic to touch it nor did we have the money to pay anyone if we wanted to.