Lessons learnt

[sntee]

I said in an earlier posting that I would let anyone that was interested know how my Cylinder head gasket change had gone.

I won't bore you all with the details but I did learn a few things that MAY be relevant to some other recent threads....

Here's my Top Ten -

1) My mystery oil loss and fumes in the cabin problems turned out to be a worn out rear camshaft oil seal. The oil was running out of the Cam position Sensor, down the back of the engine and onto the exhaust manifold. It was then burning off (hence the fumes and no drips on the driveway).

2) Exhaust manifold gaskets are a b#tch to fit - see my other thread "Vacuum Routing Diagram?" for details.

3) There is a hard plastic tube sheathed in foam insulation, that runs around the front of the engine (under the Inlet manifold) to the oil seperator and it is incredibly brittle! I managed to break mine in two places just moving it about and I've yet to discover the implications of this, so if anyone can enlighten me I'd appreciate it.

4) My Distributor and Rotor Arm were completely shot. An area that often gets overlooked when trying to diagnose faults. I'd recommend anyone with a high miler takes a look next time they're under their bonnet (hood).

5) A head gasket change on these beasts is one hell of a task for an amateur. Took me 4 full days from start to finish. I was extremely careful about every step..... and still managed to bugger it up!!!

6) Haynes manuals were written by the inventor of chocolate fireguards

7) Having said that, I followed their very vague instructions for making homemade tools as an alternative to the stupidly expensive Volvo items (cam locking tool, Cam Pulley counter hold tool, etc.) and I have to say they worked fine and cost a total of about

[matthew1]

sntee, thanks for this post-mortem on the head gasket repair, very interesting info.

putting this into Volvo Repair Database.

[MadeInJapan]

Your #3 and question related to it: It is your PCV system...a series of hoses that connects the recirculating air to an oil separator/trap under the intake manifold to the lower section of the airhose from your air filter box. It is essential to to clean it out...usually replace it. When it clogs up you get engine seal leaks- such as the rear main seal.

[stoutlogic]

Correct brittle hoses are PCV related. Replace them all at once. FCP Groton sell as kit for under $140 complete with oil sep unit.

[rothgar]

Loved your post as I am in the early minutes of doing my head gasket. My car's overall condition is too dicey to spend 2 grand on this repair. But I am having trouble with step 1 -- removing the intake manifold. I am missing some bolts since I can't get this beast to budge. So far, I've found 2 bolts under the intake manifold but am having trouble finding the third.

Any clues would be appreciated

BTW: This comes from a Volvo Master Tech. If you are having overheat or stalling problems check and/or replace your thermostat. The darn things come apart. I was told my 94 850 was toast by a friendly roadside service station -- who refused to install the Thermostat I'd bought. Got the car home and installed the new one and viola -- except for blowing incredible amounts of anti-freeze through the engine it works. It's the blowing A/F through the engine that is spurring my Head gasket replacement.

Love all the details you can remember!!

[MadeInJapan]

Hopefully this diagram will help you. For the one under the power steering pump several socket extensions and a swivel end seems to be the way everyone is doing this without moving stuff around and out of the way:

[luketrash]

Once you find that first bolt (lower left bolt on the intake) it will take a both a long and short extension bar for a 1/4" socket set along with a swivel head 10mm socket (all Craftsman tools I was using) And that's barely long enough.. An extra extension would have been nice. My back hurt for a few days after doing all that because of all the time I spent concentrating on what I was doing and taking my time, while leaning over the engine bay.

I don't envy anyone doing this for the first time.. I imagine subsequent times would go faster, but it won't ever be easy or enjoyable

[sntee]

Rothgar, how did the Gasket change go?

I'm assuming you managed to remove the Inlet manifold in the end

If not, or if you still have everything in pieces, I'd highly recommend servicing / replacing the PCV system while your at it.

The inlet manifold needs to be removed to do this and during the gasket change, you have to disconnect a lot of the PCV unions, so it makes a lot of sense. Also, reading through this forum, it seems there may be a possible link between "clogged PCV" and premature gasket failure.

[MadeInJapan]

... it seems there may be a possible link between "clogged PCV" and premature gasket failure.

Yes, but usually the rear main engine seal, which is the expensive one. So...Yes! By all means, everyone should service their PCV systems....look at it and do a cleaning every 30K miles as needed and usually by 90K miles it will need replacement.

[rothgar]

As I don't really need this car back in operation until Mid May (and I'm working like a dog otherwise) I am still doing the Gasket job. It has expanded some to include Timing Belt, Water Pump, etc. I got the Head back from the Machine shop last Friday and am preparing to put it back on.

It was kinda interesting finding puddles in my cylinders; it's warping is probably the cause of the head gasket problems. It briefly over heated at Christmas.

Right now I am trying to decide whether I need (or should get) any new cam followers. They have some abraided spots and a brownish ring on the edge of the cam facing. Could be a side effect of sitting in an oil bath for 2 weeks.

BTW: A couple lessons I've learned are:

You need a 1 inch Iron Strap to release the Serpentine Belt. You definitely should pin the S. Belt idler.