M30 Head Gasket Replacement

[Kevins34]

I am really strapped for cash right now and my Head Gasket is blown -- to the outside so it's leaking down the side of the block.

There is the right way to do this and it costs more than I can afford right now, so I'm thinking about just pulling the head, slapping in a new gasket and putting it back together again.

If I were to get the valve seats done and seals replaced, I'm sure the piston rings would be toast in short order -- the engine has around 220,000 miles on it. So I'm holding out hope that the head isn't cracked and/or warped, and that replacing the gasket will fix my leak. Especially considering the local dealer here wants 30 dollars for a gallon of that blue coolant.

So with that context in mind, here I get to my questions:

1) Do I need to re-adjust the valve lash when I'm putting it back together? If I'm not disassembling the heads, I can't see why that would be required.
2) The bentley manual mentions the use of "copper paste" on the exhaust manifold. Is this the same as that permatex gasket sealer with the copper in it or is it something else?
3) Are there any tricks for saving time when you have to go back in to do the final torque stages on the head bolts?

Thanks.

[Kalevera]

If the head and/or block aren't warped, why would you need to do a valve job or anything else?

[genphreak]

My car had 150k miles at 17 years old and the engine bores had no wear in them at all. Perhaps the oil was regualrly changed... yours might be similar... (hopes): My finger felt no lip in the bore when I felt for the point where the cylinder ring stopped coming up.

However there's a dude 'in the ghetto' that swears by an additive that seals gaskets up, though I'd never use it if I could avoid it... dunno how bad yours is, but my gasket only leaked when the engine got very hot. With a high ratio of coolant in it, the boiling point was raised and it didn't leak at all.

Add this to some gasket sealer and it could be a very cheap and quick fix!

Ultimately the radiator is only $200US, so I guess adding goo is not the worst idea as it could be replaced later on if it isn't working so well due to the goo. I imagine it'd clog it a certain amount. Worth the risk perhaps as head gaskets are not an easy or cheap job. Of course there are other things in the system that may get clogged by additives... like the heater valves and cabin heater core.

I guess the decision on doing the head gasket depends on the amount of leak. If no coolant is getting into the engine and no oil is getting into the coolant an additive might be an option if you don't care too much about the car and want to a cheap, quick but probably temproary fix.

Search this board for his thread on 'ghetto'.

Is the leak at the back at the lower end of Cylinder 6? I think a few go there (mine did) from age and from the Coolant passages clogging up and reducing coolant flow (esp. at the rear of the block). This is not good as to rpevent warpage the heat must be removed from the head evenly. As some people don't use BMW coolant (or change it regularly enough) and it might be the or a cause of this. If the head comes off be sure to clean out the coolant pockets from the block to the head if they are corroded (probably). Milling it flat won't cost you much, and its good to have a 'dude in the know' check your valvetrain. My guy looked at my valves and seats and said they were fine. I had the seats done anyway as I wanted it done once. You will only need new valve stem seals ($7 for 12, but are also in the head gasket kit) if you end up taking the valves out your guy will need these, adn probably then change the guides which are only $4 each (x12)) but it takes them some time to Remove & Repair all the valves in the shop, so that's where it will start to cost you. To mill (skim) the head flat they have to take out the valves anyway... so if that has to happen you really should get the lot done.

Perhaps you can avoid all that as you say- just check your head with a metal straight edge when u remove it, if it looks good, you might be alright to simply put her back on with a general cleanup and new set of gaskets.

If you can notice some warpage anywhere it should go to the shop for machining. Ask their advice on replacing stuff, but I reckon if you take them out, you might as well fix all the little bits up- the additional time and cost is not much in comparison to doing the whole thing again... and it'll go better. Mine runs so smooth now it's all done.

Overall it shouldn't cost that much, mainly time! Suggest you take it to someone who knows M30 heads of course- experience saves time and money. I replaced all my rockers and cam, the cam had an oil problem that went unfixed so was worn on 2 lobes, and the rockers were gone too. But I didn;t need to, the machinsit could have fixed it well with less cost. I just did the whole lot for piece of mind (like I said, I never want to do it again). If yours is someway worn somehwere (unlikely), an experienced dude will be able to suggest cheap options on anything yours might need; such as $5 parts -ie valve stem caps and oversize eccentrics, etc. available to make up for wear here and there.

Regardless, be sure to change your thermostat ($15), head bolts ($4 each) and yes, you will need to reset the valves. It's not hard - took me 20 mins once the cover was off- many people go on about the settings/finer points... main thing is to get the feel of the feeler gauge consistent accross them all, mine stick a fair amount when I push the gauge in-between the lobe and the rocker arm, make sure the gauge is always dead horizontal though. I use 0.0012 of an inch w the engine cool but not dead cold. ie Coolant under 35 odd degrees. Re-check them once you think they are right too...

Gasket kit is not much either- I use www.eap4parts.com they are really good.

BIGGEST TIP: Make sure your hoses and all connections to the engine block seal well, (do NOT overtighten them as the plastic radiator tubes break), you may have to change some pipes if they are old and clean up the water necks so they mate nicely with the hoses and seal well. Make sure the thermostat's big spring is on the engine side of the complicated-looking water housing, o-ring on thermostat neatly facing outwards to seal agaisnt the outer thermostat neck when you bolt it on. Make sure the little arrow on the thermostat points-up. I drilled a small hose in mine (2mm dia), next to the arrow to help bleed the air when it was all sealed up as the bleeder is on the radiator side of the thermostat. It's a well known trick.

Oh and the exhaust stuff they talk about, copper paste? It's just anti-seize compound from any autoshop.

Hope all goes well, let us know!

GP

[632 Regal]

pop a gasket on, clean everything including the piston tops. You must use NEW head bolts and torque as per bently, the angle method. If your not getting bad ticking from the valves forget having them done. I'm one of them people that think if it wasnt overheated then by torquing the head back down it will sit flat. No need to mess with the lash.

If you had a ton of money I would have everything done but from what you said you should be fine. I'm not sure about the permatex with copper stuff, I think Bently is referring to the copper stuff you smear on some steel head gaskets and it is a pasty type of crap.

[Kevins34]

Does the Head Gasket Set come with exhaust manifold gaskets or gaskets for the manifold -> downpipes? Or do I need to buy those separately? Same thing goes for the intake manifold. I assume it comes with a gasket for the upper timing cover.

Besides the Head Gasket set and the Head bolts, what other parts do I need?

[Hector]

oil guide seals, upper and lower TC gaskets, camshaft and crankshaft TCseals TC and maybe a few odds and ends--don't recall exactly. You need these parts just for a straight up heas install/removal along with new head bolts.

If you have the cake, there other things you can do (or might have to do) such as valve jobs, head refurbishing (if head is warped,) replacement of rocker arm shafts and rocker arms, eccentrics.

Search the archives. There are some of us who have done this type of work on the m30.

Does the Head Gasket Set come with exhaust manifold gaskets or gaskets for the manifold -> downpipes? Or do I need to buy those separately? Same thing goes for the intake manifold. I assume it comes with a gasket for the upper timing cover.

Besides the Head Gasket set and the Head bolts, what other parts do I need?

[genphreak]

If you do remove the head make sure you don't get crap down the bores when you clean the surfaces up... you don't want the bores damaged by mislaid crud once you bolt it all back together all nice and fixed up.

Oh and I edited a few things in my previous post as it was a little vague in some areas...

[632 Regal]

male SURE the bolt holes are clean and dry!!!! dont ask, just do it!

[genphreak]

male SURE the bolt holes are clean and dry!!!! dont ask, just do it!

Oh yes, a pack of cotton buds is good... and clean them with a thread chaser (M12 machine thread) if you can- the Chinese ones cost $2