Engine Head Gasket
 

Hey everyone!

I have a volvo S40 2.5L T5 2004.05 with 152 000 miles. I was wondering if it was possible to change the head gasket by my own without the need to use a special Volvo tool? I have almost all garage tools.

There is one cylinder misfiring from time to time. White heavy smoke coming out of exhaust pipe when it starts to be 40F or 4 degree Celsius, even after a long driving but when I drive over 20km/h the smoke a lot less dense. The coolant is leaking from a tiny crack on the extension coolant and I am assuming in the head gasket too which might cause the misfiring.

I am planning to do a combustion leak test soon and if it turns to be positive, then I need to change the head gasket or maybe if there is a crack on the engine, I am doomed.

Any suggestion of extra work I should do before, during and after?

It does sound like you have a potential and likely head gasket leak.
(Coolant escaping into your exhaust via at least one piston.)
does the heavy white exhaust smoke smell of coolant at all?
I am thinking you have coolant from a water jacket seeping across to one or more pistons due to gasket failure.

The leakdown test you are planning will confirm it all for you.
Visual inspection with plugs removed may show it up also.
I assume you are having to top up the coolant reservoir regularly. You have not stated so?
Look for evidence of water mixing with your engine oil also.
i.e. foamy sludge under oil filler cap or maybe signs of oil in the coolant reservoir.
Don't allow her to overheat and cook the motor causing more damage.

For the spark plugs look for a bright white "steam cleaned" plug.

Awesome! Thanks for answering! I will check the spark plug, do the combustion leak test by Sunday.

I usually fill my coolant tank once a week. Can't wait to fix it and give you news later, also with picture if I am able to do it!

I was just wondering if I need special tools?

After reading some forum, could it be coming from my turbo too? There is something about bypassing ''something such coolant line'' to test which I do not understand.

Hey man, I hear your question and I don't know the answer. If you have CVVT or whatever it is, you will need to load it properly before you start the car or install the timing belt. I don't know.

Hey thanks for answering!

I did the compression test and the results are:

Cylinder 1: 150psi
Cylinder 2: 157psi
Cylinder 3: 162 psi
Cylinder 4: 150 psi
Cylinder 5: 150 psi

Each of them, I waited 1 min to see if the pressure would decrease and no leaking.

I am going to perform a combustion leak test today and see the result.

Meanwhile, by looking my spark plug I am wondering if something is wrong since the coating is redish...

Thanks!

This is not indicitave of anything except a properly working compression gauge check valve.

A compression gauge measures and holds the highest pressure seen while cranking. It has a check valve so that the reading is maintained. Otherwise, it would instantly go to zero after you stop cranking unless you just happen to stop when all valves are closed.

Hmmm great to know that there is a check valve! Thanks ES6T.

I did the combustion test coolant leak with this chemical stuff in a kind of beaker and it appears to be positive.

After driving a few miles, I got the check engine light on.

Misfire Cylinder 1 and 2.

Fuel Sys 1 CL
Fuel Sys 2 CL-Fault
Calc Load (%) 27.45
ECT (F) 161
STFT B1 (%) 17.19
LTFT B1 (%) 4.69
Fuel Pres (PSi) 42.64
Engine RPM 1760
Veh Speed (mph) 8

Any idea what can cause the white smoke or engine trouble?

Is the plug with red residue different than the rest? If so, which cylinder was it?

White smoke is usually coolant being turned to steam. You should be able to smell the sickly sweet coolant also.

You asked about bypassing the coolant line to the turbo. On the 2000-2004 1.9L turbo models it would be fairly easy to bypass the turbo. If the 2.5L T5 turbo is similar then you could do the same to test that theory. However, your check engine light and misfire codes seem to suggest the problem is elsewhere.

Oh, you used one of those kits to detect combustion gasses in the coolant tank, right? If that comes up positive, you're gonna be pulling the head. You can do a cylinder leak test to see if pressure bubbles out of the reservoir during the test of certain cylinders, but that would just be so you know where to look when the head is off.

I have replaced a few motors with cracked blocks due to overheating on those S40s, hopefully you didn't overheat it.

Yep, I used that kits that detect combustion gasses. When I say positive, it means that it did not change color hehe, different from health result.

The spark plug are redish due to MMT fouled after some researches:
Interpreting your spark plugs

I will try to see if I can turbo bypass and I will give news back soon! I hope it is not crack either.

It has been like this for the pass 3 years where during summer time, nothing comes out and as soon as it gets around 40F, 4C, it starts to smoke a lot.

I really appreciate your help!

When you say bypass the turbo, do you mean drive the car with the turbo not getting coolant? If so, terrible idea.

I won't drive but just leave the car at idle and check if there is smoke coming out. Hehe I would never drive just like that.

Thanks again to follow up my thread!

I will send more info of what I did next week!

Cars have been driven without coolant to the turbo forever. A short drive won't hurt anything. Many, many turbos NEVER have coolant through the center section. I run a T3 turbo in another car that runs just fine without coolant through the center section.

For the record, I do not believe the turbo is the issue....but he asked.

Hmmm I just find it weird that there is so much smoke coming out like a angry bull haha! But I guess I will leave like this for now since is it really cold outside. I did another combustion leak test (chemical test with the coolant expansion tank) and it appears that the head gasket is perfect.

To add something awesome, after reading some topic forums with the fuel pressure sensor problem, yesturday I decided to change mine without any OBD code appearing and wow.... I can't believe it somehow fixed the misfiring and the car respond so much more quickly! I paid the Bosch fuel pressure sensor 91$ + tax.

I am happy to see the engine running smooth!

If the spark plugs are all the same color then you may be right at looking at the turbo.

Yep, they are all the same color. Is there any instruction about how to check the turbo? I have been looking and can't find any.

You are breaking new ground as far as I know. If you can figure a way to rig a bypass with a valve then you could drive the car until it smokes then throw the valve to divert water around the turbo then drive it to see if it smokes again. You only want to change one variable at a time. In this case the coolant flow to the turbo. Just a suggestion.

I'm not sure about the turbo coolant system but as I checked under my car, I think it is cooled with oil. Am I wrong?