It is possible to DIY if you're properly equipped. I just did this on a Toyota. Replacing the head-gasket on the 4-cyl Toyota was about a $100 kit worth of gaskets, seals, and head bolts. HOWEVER: you also need to take the head to a shop and get it checked out or rebuilt. You may have only blown your head gasket, but there are other possible failures, like a warped head, cracked head, broken valve seats, burnt valves, and in really bad cases a warped head can also bend your cams.

That can get very pricey.

You can also find rebuilt-heads on ebay, for much cheaper, but walk with great care, you can end up with a lot of expensive repairs if it's not set up right.

In my case; the head rebuild would have been $700; and a new head cost $300. In this case, the head was not even warped, but two valve seats were leaking when it was tested. So I ended up having to buy special tools to get the valves on the new head adjusted properly. It also took about 4 weeks of back and forth with the supplier who sent me the wrong head, and I had to ship it back and wait for the correct part. I would expect the BMW cylinder head to be MUCH more expensive.

You have to be VERY clean, and the surface of the head and engine block have to be perfectly smooth. There are cases where the engine block warps or cracks, and in that case, it's much cheaper just to get a new engine. If you have the head off, it is also a good idea to do pistons and rings on a high-mileage engine. It's also a good time to check the crankshaft and bearings; but by then, you're really talking about removing the motor from the car, and building a long parts list, and you'll be looking at quite a bit more than 1500.

If a shop is going to replace your head gasket at 1500, I would say that's a steal - but they're likely to run into other costly problems.

Finally: there was a REASON that your head gasket blew. Most common reason is overheating. Most common cause of overheating is a failure of the cooling system. That failure MUST be addressed also. By the time you've spent 1500 replacing the head gasket and reconditioning the head, you may also end up spending an equal amount replacing the radiator, water pump, hoses, thermostat, and expansion tank; to prevent the engine from overheating again and blowing your new head gasket.

Doing my daughter's Toyota, took me about 12 weeks (weekends and evenings; dealing with shipping delays for parts, and such). I was "handy with spanners". Honestly, every time I do a job like this, I become much handier. So there's an upside to all this. There are two critical skills that you will need to develop for this particular job, which separates the dabbler from the amateur mechanic, and that's the proper use of a torque wrench, (for which there are many tutorial videos online), and absolute cleanliness. The seam between the engine block and cylinder head is an extremely critical place, and torque needs to be perfect, and it needs to be clean and precisely smooth. This part is difficult to get to; requiring disconnection of your intake, and your exhaust, and your valve-train. You don't want to re-do it.

 

Forget about trying to replace that head gasket (for more reasons than I care to list here), it`s cheaper, faster, and easier to just replace that engine with a wrecking yard replacement.

 

Absolutely agree. These engines aren't Toyos, they require special tools (expensive ones) and decent amount of experience. We've seen plenty of guys try, and they never seem to run right when done. Cam timing is a problem without the tool. Yes, it CAN be done, but not by most (myself included). For $1500 or less you can have a whole new engine.

 

Thanks guys! Lots of food for thought there

 

Well, i believe i could change my head gasket, because non vanos 8-valve technology makes it easier than yours, but i'm still happier, when i don't need to do it.

 

So this is what I'm going to do. as I've been quoted £1500 ($3000) for a garage fix, I'm going to attempt it as a project... BUT I'm going to get a mobile mechanic to come over to do the more tricky bits. Whadya reckon guys?? Sounds like a plane to me. i just need to find out which bits I may need help with before I star, and which special tools may be needed? Can anybody help with this? Thanks again guys!

 

I think you should listen to those of us who have a TON of experience with E46s. Just drop in a new motor. It is a great and fun project, but requires no special tools and no mobile mechanic. And the results will be a car that works perfectly instead of one that will likely have timing issues, potential head bolt issues down the road, and a loss of tons of cash.

But hey, what do I know.

 

I always advocate for people to stay away from mobile mechanics unless you personally know the person. It's way too easy for a guy to buy a set of wrenches and tell people he knows what he's doing. That 1500 will quickly climb if the mechanic has to fix something else the mobile guy screws up.

 

Yeah I hear ya. I did read your advice and I looked into it. Thing is I'm not geared up to lift engines in and out. Garage has quoted £2000 to supply and fit a recon engine. Main thing is I'm broke and can't afford the new engine route (

 

So what makes you think you can afford to fix ANYTHING on this car in your present state ?
I (as well as many other veterans here) can pretty much guarantee that you will just dig yourself a bigger, deeper hole by attempting a DIY head gasket fix. Those "special tools" mentioned are not available to the general public, they are usually "Dealer-Only" items, not available for loan or rental.

Keep saving your money, and ride your bicycle in the mean time, until you can afford a proper repair job....

 

I suppose I just need to borrow a jig?

 

OP, have you received a quote for having the head checked, resurfaced and refurbed from a machine shop? You would need to factor that in.

 

Indeed....besides that, with these aluminum blocks, there is always a chance that the deck (top of the block) has warped as well.
And, you have to be careful as to the integrity of the repair facility....I once visited an "engine rebuilder" shop in Jersey City where they were using a hand-held, portable belt sander to resurface the heads & block !

 

Thanks yeah I guess I would

 

You can rent a cherry picker for $50 a day from tool rental places. Two days max is all you need. And since the entire front portion of the e46 comes off easily, you don't LIFT it as much as you just slide it straight out. Here is a pic, takes less than 3 hours to get to this point.

 

I believe it would take a day, if never did before. 3 hours for someone who knows stuff already.