All,

I have a 98 Volvo S70 (T5) that I purchased about 4 months ago. About a month ago i was driving to work when i noticed the engine overheating and smoke coming from the engine compartment. I was in bumper to bumper traffic on the highway so it unfortantally took me a few (10 min plus) to get off the road and shut it down.

I towed it home to discover that a busted coolent hose going to my Turbo. I replaced that and thought it was a success.

Ever since that day i have noticed i have had to add Coolent every week or so. Not a rapid leak or anything (actually not leaking at all because i have stuck cardboard under the car at night to see if there was one) But anyways i am new to working to cars so never thought anything about it.

Last week i was about 2 min from home when i noticed Again that the car was screaming "hot" and smoke was coming from the engine compartment. I parked it in the driveway and turned it off. I initally hoped it was the Termostat, and the engine was just not getting coolent. But after putting the Termostat in boiling water i relized that it opened and seemed to be operating correctly.

I then did a little reading and was drawn to checking the oil dipstick. Where i noticed a milky substance. Let me go back and say when i bought the car the Engine Coolent Resevor had this "milky substance" in there. And me not knowing any better purchased it. So from that day, the coolent reservor has had this milky substance, but up until that turbo hose busted had been running great with no problems.

I took advice from people and came to the thought that it was a blown head gasekt. I purchaced a book and started working. I took the Head off last night and the gasket looked perfect to me. I have never done one before so i really dont know what a "good" vs. "bad" gasket looks like. But when i took off the Inlet Manifold Gasket and the Exsaust Gasket VS the Head Gasket, the Inlet/Exsaust Gaskets were breaking and rusted and nasty, but the head gasket looked good.

Have i done all of this work for nothing? Could i have missed somthing and made a huge mistake? I have alot more questions as far as putting it back together so i hope there are alot of veterans that are willing to help.

Thanks in advance!

-Josh

 

There is a lot of information in the 850 section to gleen from.

 

More than likely, this is the source of the problem. Typically, you'd put a pressure test gauge in the system to check for combustion pressure leaking to the cooling system.

You've got it off now. Have the head checked for flat at a machine shop. If necessary, they can true it with a skim cut. The specs are in your book.
Sometimes the gasket shows an obvious sign and other times you may only notice a discoloration of the gasket or the area of the head surface where the leak was.
Ed

 

Was there white smoke comming from the exhaust? How does the oil look is that milky?

 

The milky appearance on the oil dipstick is not unusual on these cars- it's usually from condensation, especially if it can be found all the way up. This is caused by a plugged PCV system. A blown head gasket will typically have obvious damage around one or more cylinder sealing rings.

Since your engine has been overheated a couple times, it is very important that you take your head to a machine shop and have it checked for cracks and warpage. If it is cracked or warped, they can repair it, unless it's too severe. Give them the valve stem seals that will come with the head gasket set so they can put them in, too. Change the thermostat, as well- overheating can cause damage to them, as well, which may not even show up right away. While the head is off, you'll want to do the PCV system as well. Order the kit from FCPgroton or IPD, and make sure that when you take off the oil trap that you clean out the ports in the block where it attaches. Use a small bottle brush and some solvent to do this. You should be able to get a thin, flexible strip of some kind far down in once these ports are clean. When you put it all back together, make sure to use new head bolts. Now is also the perfect time to change the timing belt, as well as the tensioner and idler pulleys. If the car has over 125,000 miles, it might be a good idea to also change the water pump and hydraulic tensioner cylinder. Yes, these are a lot of parts and a good bit of money, but now that the engine is apart is the best time to do all this. You'll be glad you did when you get it all back together and have a nice, trouble- free car for a long time afterward.