head gasket repair

omojamie · Post by **omojamie** » 19 Jan 2011, 09:34

I have a 1998 xc70 wagon w/ 190k miles. I had a head gasket failure which I decided to repair.
The mechanic has done the repair and the engine runs fine, except for an oil leak that causes white smoke to come from between the engine and the passenger compartment.
He can not make it stop. He gave it to me to drive for a few days (it was smoking intermitently) and it started running really rough, apparently 2 cylinders are not firing correctly (if at all).

I am not sure what to do and how to remedy this situation if he continues to try and fails.
Do I/can I ask for a refund (whole or partial)?

Any advice (other than "you shouldn't have fixed it") would be greatly appreciated.

Thank you.

Post by **jimmy57** » 19 Jan 2011, 10:02

Has he identified the place where it is leaking but just can't stop it or???
DO you have any more info on why it is missing on two cylinders?
Has the mechanic tried to diagnose the missing problem?
Does it have any noises like exhaust leakage?

Post by **JDS60R** » 19 Jan 2011, 10:47

Bring it back to the mechanic. You most likely still have a head gasket leak and the white smoke is leaking antifreeze being vaporized and coming out any exhaust leaks .

Either way - The engine needs a leakdown ,compression and combustion gas test to find out why the cylinders are missing. If I did gave back a motor that was misfiring on 2 cylinders without an explanation I would expect to be in front of a screaming customer.

omojamie · Post by **omojamie** » 19 Jan 2011, 11:28

I have not noticed any exhaust leak sounds.
He thinks the leak is from the cam seals. ???
He also thinks that the oil leak has compromised the distributor cap, which he is cleaning.

It smells like burning oil, wouldn't anti freeze from a head gasket leak smell "sweet"?

He had said something about removing the valve cover and using some sort of spray sealant and closing it back up.
Does that make any sense?

Thank you so much for your replies.

Post by **jimmy57** » 19 Jan 2011, 11:37

HMMM.
That engine uses an anaerobic sealant to seal the cam cover to the cylinder head.
The head and cam cover have to be very clean on the sealing faces and the sealer is applied with a roller to the upper part only in a thin film just like paint. Then the cam cover is fitted to head and bolts installed and torqued. If too much sealant or wrong sealant is used then gaps can let oil leak in a lot of places around the perimeter of the cam cover and into the spark plug holes too.

omojamie · Post by **omojamie** » 21 Jan 2011, 08:47

OK. I don't have the car yet, but he said that the oil leak is fixed (cam seals) and that one of the cylinders is firing, but the other (#4) has low compression and is only firing when the engine runs over 2k rpm.
He put some sort of lubricant in it and hopes that will allow it to run smoothly at idle.

I never had any trouble at all before the head gasket failure what do you think I should make of all this?

Post by **JDS60R** » 21 Jan 2011, 10:09

If we knew the compression reading on the cylinder we could tell you more.

I'm assuming a no fire due to low compression. He is hoping its the rings and that a cleaner or restoration product will help

The engine needs a compression and a leakdown test so you know where you stand.

Please share the compression readings with us.

omojamie · Post by **omojamie** » 21 Jan 2011, 15:09

50 psi at idle
120 psi at 2,000 rpm

Post by **JDS60R** » 21 Jan 2011, 17:25

Then you have some real mechanical issues going on.

If cam timing is correct then,

Perform a leakdown test and confirm where the loss of compression is coming from.

Post by **JDS60R** » 21 Jan 2011, 17:30

Normal compression for that cylinder at idle is 174psi top 203 psi (1.2 -1.4 Mpa)
Procedure and spec attached