To fit a new silicone inlet pipe, I've spent the last few days getting the manifold off and now I'm looking at the bare engine - at last.

I found I had a problem with a snapped rocker cover bolt that had been leaking oil on the offside and the break is in the threaded part so thanks to all the help I've had on here, I've worked out that I'll need to remove the rocker cover, then the cam cover to get at the head itself, then try and drill the snapped-off bolt end out of the head, or use a screw extractor. I've already been advised to wait until the Spring and just seal it up for the time being, which sounds like good advice - I've cleaned out the muck that was in the bolt hole and sealed it over with hermetite gasket stuff and the rocker cover's in no danger of coming off.

But now the airbox, manifold and fuel rails are out of the way, all my tools are to hand, I have the parts I think I need to do the job (new rocker cover gasket, two plug tube gaskets, six new bolt washers and the all important new bolt!)...should I just dive in and try and fix it? It's the top left bolt, which is just obscured by the big black vacuum pipe - you can see a tiny speck of orange behind the pipe where I've sealed it.



What horrors await me if I get the rocker cover off now? Will oil or coolant **** out everywhere? Or will tiny pieces of the valvetrain go pinging off when I take the cam cover off? I was fairly confident that nothing too bad could go wrong when I took the manifold off, as everything underneath was horizontal. Isn't all the head gubbins going to just fall out when I start delving under the rocker cover? And is it something that can be done in a couple of hours? Help!

 

There wont be any parts dropping off by taking the cam cover off, except for some amount of oil. The tight restricted space around the engine to remove a broken bolt, wouldnt it be better to remove the whole engine and do the work on a bench/engine stand

 

The snapped bolt is around 45mm you would need to get that angle perfect and I would imagine that to be a little tricky given its position. Also think about the metal filings from drilling you don’t want debris in the engine and again the angle might to be a problem to see where the filings drop.


Removing the rocker cover will hold no surprises but a little oil...

 

Why would you wait till the spring to do it as opposed to now?

 

Well I am worried about how tight it is in there, but the thing is I can't see how I can improve things without, as you suggest, lifting the engine. And I don't have a crane to do it with, so that's out of the question. Nor do I have a big enough garage to have the engine out on the bench AND my car in bits simultaneously.

Good news about nothing falling out except oil, but what are we talking about? A few drops or half a litre?

First thought I had was to drill it out, but then if I can't get my big cordless in there, I might try a little hobby drill I've got, although it may not be powerful enough for the job in hand. But then again, I'll be working up from something like a 1.2 mm drill bit, so maybe it'll be ok. I do have an extractor set, penetrating fluid and a blowtorch - might one of those be a better bet for this delicate task?

BTW just thinking of waiting until the spring because it's bloody freezing - literally - in the garage at the moment. But on the other hand, I've already cleared most of the ancillaries out of the engine bay so it makes working in that tight space a little easier.

 

Would having someone holding a hover tube while you drill, maybe help in reducing metal filings getting into places you dont want

 

Yes that's another idea...

 

It's not that much oil but goes surprisingly far on a garage floor.

You'll never get a hoover, a drill, you and your mate with the hoover all in the same place at the same time. Get some newspaper and tape and mask off the rest of the head. The head is alloy but the bolt won't be so get a magnet to get the last of it out.

If you undo the engine mounts and take of the stabilizing bar you can jack the engine up some to help but if it were me I'd take it out.

 

Do you know where the bolt is snapped? is it the head of the bolt or is it snapped flush with the cylinder head? if its just the head of the bolt, when you take off the rocker cover there will be part of the threaded section of the bolt still visible. You could apply some head to the corner of the cylinder head causeing it to expand, keep the heat away from the bolt!! then spray some release spray in, you could remove it with a tap wrench or mole grips.

If its snapped flush with the head it will need drilling, wouldnt use a 1.5, to much chance of it snapping and getting stuck, then your f***ed! you cant drill out snapped drill bits!! See if you can punch it with a centre dab, and start with a 3.5 or a 4. If its a m8 your guna need a 6.8 bit and a m8 tap. if all the fails you can drill it bigger and use a helle coil.
The lata would be your best bet if its snapped flush with the head!!

Ps you can also get left hand drill bits (very rare!) there very good for stuff like that as they can unwind the bolt while drilling withont the need to re-tap.
wez

 

If you using a stud extractor make sure you drill the right diameter and depth hole! it will tell you on the pack! In my experience there a nightmare on small bolts! have a tendency to snap inside! If that happens there like a drill bit (hardened) and cant be drilled out!
wez

 

Yes I think I'll mask the whole area off, that should make things easier. I've got the dogbone off (the gearbox - bulkhead link) so the engine mount thing might be an option. I'm just afraid that if I lift the engine at all, I'll start popping out water hoses and hard pipes everywhere.

 

Wez - Where it is at the moment, I can't get my big cordless drill in anyway unless i lift the engine somehow. And my little fake Dremel has so little torque you can stop it with your fingers. And it's definitely snapped below the head, as half the thread on the bolt is totally missing. From what I've been told, the plain shoulder part of the bolt goes through the cam cover and sits flush on the head. Therefore the snapped part must be below head level.

What are my chances then? Can I get the extractor to bite without drilling a pilot hole first? Can I still use the technique of heating then spraying in some lubricant to help things out, or is this impossible because it'll be in so far?

 

A hole must be drilled in the bolt to use the extractor. Your best bet now would be to loan a angle head drill and use a helle coil to sort it out. you need to go to a good nut and bolt shop and get a hele coil. the head will need to be drilled bigger to insert the helle coil, its like a insert made just for this type of thing, if you do a seach on the net u'll see what i mean.
Its not a major problem, easy sorted with the right gear! You may need to shorten the drill bit to fit the drill in. the hard part is going to be punching the centre of the stuck bolt! You need to be bang on in order to lign up with the rocker cover!

 

i really wouldn't attempt this with the engine in situ! you will need to drill dead straight or you will make a mess of the whole thing and potentially trash the entire head!!!
You could take off the cam cover though and see of there is a bit of the stud protruding that you could get a purchase on and maybe wind it out that way?
You can get special stud removal tools that can grip as you tighten them (obviously in a reverse thread type of way) but they are quite expensive and you will need to got the correct sized one.
Easyout's are crap imo as if it is too stuck then they will just snap as they are very hard and brittle!

 

So here's another idea. Is it possible to remove the entire head without lifting the engine?

 

it is less work to remove the engine..

 

That's what I was wondering. So it looks like for the time being I'll go back to Plan A - leave the damn thing alone and tackle it later on LOL

But thanks for all the advice, everyone...I will keep it in mind for later on. I'd love to get into that head and see whether it really is an STi 5, or a 4 but guess I'll leave it now. Although the new inlet manifold gaskets fit the heads spot on, whereas the fit to the manifold is noticeably out.

Another interesting thing I checked is the rocker cover breather outlet. I always wondered whether it has a one-way valve in it so it can only draw fresh air IN from the inlet pipe, but it seems to be totally open. So the tale of these rocker cover breathers sometimes reversing their flow and venting OUT into the inlet pipe under full boost may be true.

 

There not sti5 as the inlet manifold bolt holes (x4) would be offset.
Yours look inline, so they could be v3/v4 sti heags but you will need to remove the cam cover & possibly the cam to check further to be sure.

Ticky

 

Those heads are wrx v1-2. No telling with the covers on if they are RA heads or not.

 

The holes are definitely all in a straight line. And if they're v1-2 WRX heads then let's hope they last a while before needing changing. What would be the difference between the RA ones or normal ones? Would they have solid tappets rather than hydraulic?

 

RA ones have solid lifters and a higher RPM limit.. along with differant cams (I assume, not compared them).

Paul has taken more apart so may know more.

Simon

 

Another picture might shed more light on them?
Left hand head (nearside):



Right hand head (offside):

 

I would cover those intakes I little better until you no what you are doing, so easy for somthing to find its way down there, and that’s the last thing you want..

 

no more info from the pictures.. you need to remove a cam cover and possibly a cam to know further..

Simon

 

Well I'm going to refit the manifold today, so I'll give them a quick hoover out before taking the paper towels out. Still in two minds about whether to take a rocker cover off to have a look. Would it be possible to measure the cam profile without removing it? And can I get away without replacing the gaskets if I'm careful?

 

Need to remove a cam and pull the cap off the ligter so it can be seen if it has a solid shim or hydraulic tappet.. you could measure the cam profile but as little is recorded about them you would have very little to compare it against..

I measured the lift on Sti3 cams and compared that to UK98 cams..

I think tbh you have standard uk/wrx heads and been told they are something that are not.

Simon

 

you don't need to remove the cam to tell an RA head!

 

Are the Ra heads over bucket shimmed?

 

Well if I can do it without pulling a cam out, I might have a crack at it.

 

If you're going to take a cover off just to see what type they are you might consider doing it with the one with the non-fubar'd bolt. If you break the seal on the damaged one and try and reseal it up with 5 bolts you may have a problem.

If you're taking it off to have a crack at fixing that would be a different story