No room to pull last two head bolts near the firewall

[Thradya]

So, this is e23 specific, but maybe it's the same case with e28. Any ideas?

Also, how screwed am I? What I did recently, please don't judge:

1) Some time ago I pulled 4 head bolts to remove the oil pipe for cleaning. I had a massive hangover I didn't think what I was doing - after cleaning the pipe I put the bolts back in (without removing the oil in bolt holes...), torqued it by hand and called it a day.
2) Since the coolant level was constantly getting low (about a quarter of a liter per 600 miles? maybe less) and there were no apparent leaks, I've decided to retorque all the head bolts last weekend. I've removed all of them besides the last two by the firewall (no room to remove them), cleaned the holes, put the bolts back in and torqued according to spec (the early one, ending with 100nm after 15 minutes of setting time). Since I couldn't remove the oil from the holes by the firewall, I was super extra slow when torquing not to break anything.
3) I've done about 60miles (not 600, just 60) and about a quarter of a liter of coollant is missing

Any ideas what to do next?

[Shawn D.]

1) Some time ago I pulled 4 head bolts to remove the oil pipe for cleaning.

Why? What need was there to do so?

Any ideas what to do next?

A head gasket.

[Mike W.]

No need to worry about pulling the head bolts, cleaning the holes isn't going to do any good.

On the coolant consumption, I'd do things like checking very carefully to make sure the water pump isn't slowly leaking out of the weep hole. Next, pressurize the cooling system to check for leaks. I had one on an E12 long ago that was on the hose that goes to the back of the head. It never dripped down to the ground and the only way I found it was to pressurize the system cold so I could feel for leaks better than when it was hot.

However, it's entirely possible you have a blown head gasket or cracked head. Any signs of water contamination on the oil filler cap or the coolant cap? The oil filler can sometimes have whitish goo on it, the coolant cap can sometimes have some oil on it and the rubber on the seal can sometimes distort.

[Thradya]

Why? What need was there to do so?

To remove the oil pipe on top of the camshaft. Brain fart as I said already, should have tried to wiggle it out without removing the bolts.

A head gasket.

Hence my question about the last two bolts near the firewall - I can't remove them, there's no room. Only thing that comes to mind is removing the head with the last two bolts in - but it depends how much of the bolt is sticking out on the other side of head. I don't want to do all the prep and then not be able to remove the head without moving the block.

However, it's entirely possible you have a blown head gasket or cracked head. Any signs of water contamination on the oil filler cap or the coolant cap? The oil filler can sometimes have whitish goo on it, the coolant cap can sometimes have some oil on it and the rubber on the seal can sometimes distort.

Head was replaced last year because the old one was cracked. Current signs are as follows:
- white smoke before engine gets up to temp, though it's freezing right now
- rather unpleasant exhaust smell - not sure however how it's supposed to smell though - there's no cat and it's l-jet with no lambda sensor. Absolutely no emission controlls of any kind.
- no apparent leaks
- eats coolant, oil not so much
- no apparent oil in coolant, also no whitish goo anywhere besides in the hole of one of the head bolts that I've removed recently - seems like I've cracked the block torquing the bolts without cleaning the hole.

I really need to stop monkeying around with this engine and finally do the M30B35 swap.

[slammin_e28]

I really need to stop monkeying around with this engine and finally do the M30B35 swap.

This.

I'd put up with the coolant issue while getting the B35 ready to pop in instead of wasting resources on this engine.

[Blue Shadow]

Not loosening all bolts according to the procedure (correct order) you have caused bad juju on that head gasket, doubt you hurt the block or head.

Then retorquing the whole thing without getting the rear bolts involved continued along the lines of it ain't gonna be right.

Shawn is right head gasket time.

Can't get to the rear bolts, remove the tranny brace and jack up the tranny to tilt the motor up in back. Watch out for the fan, maybe remove it first.

[Solarphil]

- seems like I've cracked the block torquing the bolts without cleaning the hole.

Likely this. I made similar mistake once. Pulling the head bolts and simply reinserting them without cleaning the bolt holes traps oil in the bottom of the hole. If the hydraulic force caused by torquing the bolts didn’t crack the block, the thermal expansion of the oil certainly will. Fortunately my mechanic guru caught me before I totally hosed my block, but it definitely set me back.

[Thradya]

Well, just for fun I've done a compression test. Results are kinda strange though. During the last test before fucking with head bolts, 5 cylinders were in 135-145psi range, and cylinder number 4 was ~120psi. Right now cylinders 1-5 are ~150psi (though the reading jumps a bit around with each stroke - I don't remember it happening earlier) and number 6 (the one with not properly torqued bolts) is at 130. Miraculously it stopped drinking coolant too. I wonder if my mechanic torqued the bolts to spec when replacing the head.

Thinking about removing all head bolts again (and deadening material on firewall + some messaging with a hammer to remove the last two bolts), clean everything properly, let it sit "relaxed" for a bit and then torque everything up again to spec. I reaaaaaly don't want to pull the head right now and this should take about an hour or so - I wonder if it will screw anything up even more.

I've read somewhere that most of the blocks are cracked around the bolts these days and it has no impact on how the engine runs - yucky bolt holes are the only problem?


As a side note - with idle set to ~1.5% CO it idles like complete shit when cold. The emission testing guy also said it burns oil due to high level of hydrocarbons (what?) even though it does not. When engine is stone cold it needs about quarter of throttle to even start rolling - over 1k it pulls like usual though. Ehh, l-jet is apparently way above my skill ceiling - without a computer to tweak and tons of sensors I'm completely lost.

[tn535i]

Had an M20 that significantly slowed a coolant leak when I re-torqued the head bolts. But I would never loosen them first. That was a 'why not' it's broken anyway' approach. I gave each bolt about a 1/4 turn in proper order and it was better. And I was surprised how loose the bolts felt. But the coolant use began increasing again.

If the gasket is bad you'll not fix it without replacing the gasket. If the head is cracked, as it could be given what you have done with it, then your not going to salvage. Some have had good luck with various coolant additives designed to seal cracks and small leaks. It might be worth a shot but again only because 'why not it's already broken'.

I would also guess it's likely you are getting coolant in one or more of the combustion chambers. It will make it run poorly at lower speed when the amount of coolant is high in proportion but higher up it might act just fine as the amount of coolant becomes insignificant. You might try leaving the cap OFF the reservoir so there is no coolant pressure and see if it runs any better.