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[Tezray]

Markiec and sounds2k, both very nice omega's! I think they look fantastic in black tbh, maybe in the future i can find myself a nice black elite  

Andy B, i have considered that option but i don't like using grease in the heads tbh....I could wash it off with parafin i suppose. With the spring clamp in position it's also hard to get good access to the collets as well  

Kev and Mark, thanks very much   I have been struggling with some stuff stuck on the heads, but i've been using engine degreaser...i'll keep paint stripper in mind though for tougher stuff. I'm attacking the passenger head tomorrow and hoping to get the majority (if not all) of it done.....then it's off to the machine shop to get them skimmed! Then the rebuild begins  

As for starting on the first turn of the key, in my dreams!   But hopefully all will go my way....Fingers crossed.

[Marks DTM Calib]

Only skim the heads if they need skimming, get the machine shop to check flatness first as on a V engine, taking material off the heads tends to push the inlet manifold out of alignment (depends how much you take off). Plus the V6 heads rarely warp.

[Tezray]

But if he only took off afew thou surely that couldn't make that much difference to how the manifolds line up? But if you think it could be a problem, then i'll get him to check them first. The engine didn't overheat when the gasket went, so i thought they way not have warped.
But for about 3-4 weeks previously the engine had been running hotter than normal (it'd raise to just over 97.5 degree's, whereas normally it'd barely venture over 95), so i was concerned this may have warped them slightly.

Also, i was looking forward to slightly higher compression lol

[Marks DTM Calib]

If you want higher compression then fit the 2.5 heads......with the 3.0 exhaust valves.

A few thou would probably be ok but, not worth doing if they are already flat........the Rover ones are amusing as I have seen 30 thou taken off them and the inlet manifolds then need stuff removing to get them on....

[Tezray]

I was considering the 2.5 heads, but decided i didn't want to start messing about with things, i'd rather get it fixed! Well i'll take your advice then and have them checked for flatness.....Could i not do that myself though?

I'm also going to heatwrap the exhaust manifolds before re-fitting, any advice on where to go for the heatwrap? Demon tweeks?

[Marks DTM Calib]

Its hard to heat wrap the manifolds as there is nothing to wrap the material around plus the hear shields do a very good job of reducing the heat.

You could try checking the heads are true if you have a very good straight edge.

[Tezray]

I was going to try to 'lay' the heatwrap on them, i was hoping it would stick! I'm going to have a look at the heads now...

[Tezray]

*****UPDATE*****

Finshed the passenger head today! So it'll be off to the machinist tomorrow to get them checked for 'trueness' and if they need skimming they'll be skimmed.....Then it's engine rebuild time  

Pics;



Passenger head that i finished today......



Both the heads together......So that's 24 polished + re-seated valves, 24 new valve stem seals, heads cleaned up, exhuast ports and manifolds polished and inlet and exhuast ports matched (casting marks smoothed out). Should be a cracker when she's back up and running  

Any tips on cleaning up the cylinders and piston crowns? Or any general tips on the rebuild? Cheers,

Terry

[Marks DTM Calib]

There might be a small amount of carbon at the top of the bores, I bet there is no wear though.

Similarly for the piston crown, small carbon build up but nothing much.

I use a stanley knife blade at a shallow angle to just scrape the crabon off.

[GaryB]

Or, to minimise any risk of scratching something when you don't want to, use a wooden or plastic scraper - the classic is an old toothbrush handle, ground (or filed) to provide a sharp edge which will remove the carbon safely.  A smear of grease round the top of the bores as you clean the crowns should stop any crud getting to the rings, but looking at the care you have taken so far, you had probably thought of that already.  Hope it continues to go well!

GB

[Tezray]

Thanks for the advice guys  [smiley=thumbsup.gif]

I must admit i thought a stanley knife might be a bit dangerous, but i'll see how stuck on it is tommorrow. I haven't really had a good look yet, just smeared grease all over them when the heads came off.

If i did put a tiny scratch in a piston crown/cylinder, should i just use 1500 grit to try to smooth it over? Just to try to polish it out?

[v6man54deg Geffd]

Pity I have been away - I have a special tool to get the collets in - makes the job a lot easier  

Cheers Roy  

I'm getting much quicker at doing each valve now, it's getting the collets back on that is a complete a-hole sometimes lol And i'm not a vary patient person!

Should be good once the engines all back up and together again. Touch wood i should have a fair few miles of trouble free motoring....Once it's rebuilt it will have had;

-New radiator
-Crank sensor
-Oil cooler
-Thermostat
-Rocker cover, exhaust, head, basically every gasket under the sun!
-Cambelt kit fitted around 2K ago

So let's hope she runs like she's just rolled out the factory  

Have you got any pics of your Black omega? I've always wanted a black omega....You don't see them anywhere!

[Marks DTM Calib]

Thanks for the advice guys  [smiley=thumbsup.gif]

I must admit i thought a stanley knife might be a bit dangerous, but i'll see how stuck on it is tommorrow. I haven't really had a good look yet, just smeared grease all over them when the heads came off.

If i did put a tiny scratch in a piston crown/cylinder, should i just use 1500 grit to try to smooth it over? Just to try to polish it out?

You will be hard pushed to scratch the bore with a stanley knife blade, as said, just keep the angle shallow.....the piston crown you might a bit but, its not as important.....a green scourer also does the piston tops quite nicely.

[v6man54deg Geffd]

don't forget to take your dowels out of the head and put them back in the block.
V6 head don't normally need re-skimming unless the temp goes upto 120 degs - thats the point were they warp!!!!!!  although its common to find some errosion around the water jacket face.
2.5 heads have a different shaped combustion chamber - total different shaped head gasket - don't think you would see much of a difference in performance by increasing the compression due to the engine management using anti knock control.

The best 3.0L gaskets to use would have been from a 3.0L saab turbo - these were also used on the later cadilac catera - they were metal ply gaskets same type used on 2.6 & 3.2L V6 engines.

*****UPDATE*****

Finshed the passenger head today! So it'll be off to the machinist tomorrow to get them checked for 'trueness' and if they need skimming they'll be skimmed.....Then it's engine rebuild time  

Pics;



Passenger head that i finished today......



Both the heads together......So that's 24 polished + re-seated valves, 24 new valve stem seals, heads cleaned up, exhuast ports and manifolds polished and inlet and exhuast ports matched (casting marks smoothed out). Should be a cracker when she's back up and running  

Any tips on cleaning up the cylinders and piston crowns? Or any general tips on the rebuild? Cheers,

Terry

[Tezray]

Got the heads back today, freshly skimmed   I talked to the bloke in the shop and he said I should have them skimmed really as a matter of course....And tbh i really wouldn't want to rebuild it and then find a problem so i had them done;





The rebuild should commence very soon, i'm just trying to steal some of James' (Vectrolysis) time away from his new child to get me started off! V6man, thanks for the info....Tbh it is fairly impressive that these head gaskets have lasted for 158K! I'm sure if i keep the car long enough the engine will die of bottom end failier before the gaskets go again! Oh i cant wait  :-/