head or motor?

[colombacho]

I just got my car. an E30 cabrio. When i bought it i thought i was only gonna need to replace the valve cover gasket. but after purchasing i noticed that the head gasket is leaking like a mofo.so... i am thinking of replacing the gasket, but dont know if this will be to complicated.

the options are:

take off the head and if it is not warped, mill it, replace all the things that go with it and
Replace the gasket.

or

save the headache and look for a swap. According to posts i've read they are running for 500 or so.

any advice? i really need it.
Also if you have not noticed i am not very mechanically knowlegable. My friend will help me all the way. well basically he will be doing all the work and i will assist.

[Mike325]

How many miles are on the motor? If there are a lot, it may be smarter to go with a good lower milage one.

[colombacho]

159K. does that merit a new one?

[nando]

159k is still a baby. unless you are really itching for a swap, I'd just recondition the head and put it back together. an M50 swap isn't going to be significantly faster anyway.. and there's no way you are going to do one for $500. besides that, putting in a new headgasket is a LOT easier than swapping motors!

[colombacho]

well the thing is that the guy that is helping change the gasket has not worked on bmws, he...how do i say this , Uhm... works on domestics.

he is pretty good, race engines, transmissions, etc.
Plus the m20 does not look to complicated to work on. compared to the e46 2.5L.

So, if it is a lot easier to just change the gasket, would we be ok with the 101projects book that pelican parts sells,as the source to get torq specs, tech data, etc.. or should i also get the bentley manual?

[nando]

it's not difficult at all. just make sure he knows about torque to yeild bolts, and use zip ties to compress the spring on the tube that's under the intake manifold when he puts it back on. everything else is just nuts and bolts..

the bentley is a great resource to have, I would get it as well anyway. read it cover to cover sometime, just watch out for the errors..

[colombacho]

ok, feel more at ease now. I will start on this, and might have some Q's along the way. Thanks for the responses.

[colombacho]

alright, is it recomendable to take off the head with out milling it?
the reason for this is due to that if i send the head to the machine shop everything needs to be taken off the head.
the other way i just clean with a plastic brush pad and place the new gasket.

I am trying to be practical and keep the cost down. it is gonna be a daily driver, but then again, it is not a slush bucket, its a bimmer. suggestions?

[strad]

I've never done head work either, but I've read a bit about it. My understanding is that the mating surface needs to be perfectly flat and smooth and square (not warped). As long as it checks out in all those ways you're good to go with no machine work required. I'm sure you could get a machinist to check it for you if you're not sure -- don't have to take it apart to check the mating surface.

[StereoInstaller1]

I yanked the head off of my GFs 325i, pressure washed and degreased with a toothbrush EVERYTHING I could possibly get to, cleaned every nut and bolt, bracket, etc. I painted everything I could (except a couple of things I forgot, duh), carefully reassembled using fresh gaskets and seals, new valve guide seals, new timing belt, tensioner and water pump.

It runs like a champ, and looks a million times better than mine does.

Let me offer a few suggestions: Have a BUNCH of latex gloves on hand (duh, bad pun) so you get less filthy. If you do not have a bench grinder with a wire wheel on it, get one. That is the best way to clean nuts and bolts.

Have a digital camera handy, Take pics of EVERYTHING as it comes apart.

When you pull something off of the motor, put it in a ziploc and label it!

I don't know if you saw the thread of rebuilding (on the cheap) of my GF's motor, but I spent about 60 hours total, most of which went into the motor.

As another point of reference, I pulled all but the studs and valves off of her head. Looking back, I wish I had pulled the studs too, as I ended up doing those later to make a fresh sealing surface for the intake and exhaust manifold.

The machine shop pulled the valves, inspected, replaced valve guide seals, and reinstalled the valves. Surfacing the head and pressure testing was about $125, BTW.

Luke

[colombacho]

nice info man. thanks!

now the bi@tch of everything.i found out today, ther is oil on my spark plugs.:curse:
i pulled them out just out of a gut feeling, and yes! there was oil on them. not a lot but enough to start creating a film over the posts.

this took me by surprize because i have not seen any blue smoke comming out from the exhaust. or maybe there is not enough oil being burnt to be noticeable. so it just looks worse and worse. dunno if a rebuild is worth it.

Maybe a swap? any places were i can look for full swaps? :sad:

[StereoInstaller1]

Valve guide seals are a known weak spot. Pull the head off, pull the rockers and rocker shafts, then the cam.

Have a machine shop pull the valves and see what shape your seals are in.

Luke