headgasket progress

[parakeats]

so, I finally got round to taking the head off today, and I did indeed find my suspect, a blown head gasket! used the wiki for doing this process so didn't take many pictures of how I did it





I don't think I need to get the head skimmed as it never actually overheated, just used to lose water and misfire on startup - assuming water was leaking into the furthest back cylinder overnight and making the plug damp.

also discovered some perished hoses, gaskets and fuel lines along the way so will replace those on the rebuild.

How would you guys recommend cleaning the surface to put the gasket on when I go to put it back together?

[ross_jsy]

Block of wood the width of the head/block and some 1200 grit sandpaper. Long smooth strokes not focusing on one area. Fill the bores with rags and give them a blast with a vacuum cleaner when you are done.

Obviously not the best way to do it, however it works.

[parakeats]

Thanks, will give that a go

you Don't happen to know if there is any difference between the 1.7mm and 2mm head gaskets for a 1990 318i do you? (apart form the 0.3mm...)

Trying to get the right set as I need most other gaskets aswell - any recommended makes?

http://www.onlinecarparts.co.uk/car-bra ... asket.html

[ross_jsy]

The thicker gasket is to raise the compression back to standard after a skim to remove warping.

I always use Elring. Victor Reinz also have a good reputation. Both have supplied gaskets to BMW for OEM parts

[parakeats]

cool thanks for the information!

I'll get these ordered up and hopefully I might be putting it back together this weekend!

[parakeats]

is it worth sending the injectors away for cleaning/refurb? dont think they've ever been done and it's got 124k on the clock

[ross_jsy]

Well worth it, escpecially while everything is apart

[parakeats]

Will have to work out how to take them off, seemed pretty stuck when I took the intake off!

Another thing, am I able to reuse the rubber o-ring seal between the area just above the water pump to the head? mine looked alright, but figured I may as well change it while I'm there, but I can't seem to find it on realoem if anyone can provide a link that would be ideal

the o-ring sits just at the top of this diagram above where the water pump goes

http://www.realoem.com/bmw/enUS/showpar ... Id=11_4328

[Brianmoooore]

http://2009.bmwfans.info/parts/catalog/ ... hed_parts/

[parakeats]

it just #2 labelled o-ring?

[Brianmoooore]

Yes - one for standard head gasket, and one for the thicker version.
Sure it's not included in a head gasket set?

[parakeats]

I couldn't find a set that would specify if it has the 1.7mm gasket or 2mm one... so I'm looking into buying the bits I need seperately - working out cheaper, but I'm sure I'll forget most things I actually need

[parakeats]

What level of cleanliness am I expecting to get the head and block surface too? I know ideally I want it as clean as possible, but I'm struggling to move some bits, even with 1200 sandpaper

[bmw9818]

not gonna buff it back shiny, as long as it feels smooth all over with no roughness

[ross_jsy]

Just clean enough. The head and block need a bit of texture to bite the gasket so it's not like you are aiming for a polished finish.

Drag a straight edge across it. It will highlight any high points

[Brianmoooore]

There's a difference between 'clean' and 'polished'. As said above, the surface should have texture, but it should be totally clean, as in no traces of old gasket or deposits left, or corroded surfaces. Checking with a straight edge is essential, in all directions, and I'd still recommend a light surface skim in most cases..

[parakeats]

gettign round to cleaning it up, but spent the entire weekend hungover so very little progress! trying to source a couple of the 45mm fuel hoses for the injector rail - ECP and halfords don't have the right diameters online for those and the vacuum line coming off the fuel pressure regulator, good places to get these from?

I did however buy a shit ford focus for £250 to drive round picking up the bits I need to get a proper car back on the road!

[ross_jsy]

What do you mean 45mm fuel hose? They are 8mm ID hoses

[Simon13]

this is epic. Just get a 4 inch grinder and clean up the head mate, use a straight edge she'll be grand

Getting the head refaced is a must for a good lasting repair. Its one of the basic must dos on engine stripping and rebuilding.

If the head is straight then a reface only takes of 2-3 thou by skilled machine operator. A human hair is 4 thou so you won't need a thicker head gasket.


Sandpaper is a major bodge fest best left for chimps

[ross_jsy]

I've probably done 10 + heads with little more than sandpaper and a straight edge (the most recent being my m30 head). My reasons are different, there isn't anywhere on the island that can skim them any more so add £100 + to post it off island and get it returned.

Of the cars I know of, none of them have suffered any problems with sealing the head. The oldest ones were done 9/10 years ago as an apprentice mechanic.

As I said, it's not the best way and if I could get my heads skimmed easily enough I would always do it that way. But it's also been used for years. I know of several rally boys who finish heads with sand paper glued to a sheet of glass.

Smashing a cam in the wrong way, not checking the timing against crank degrees on an aftermarket performance cam, not turning the engine over by hand checking relief with clay before final assembly and shagging your lump IS a an actual bodgefest best left for chimps. However cleaning up a head for a lowly 4 pot and checking it with a straight edge is fine. A headgasket can take up .1mm+, easy to check with a straight edge, a feeler gauge and a torch.

[E30spud]

Smashing a cam in the wrong way, not checking the timing against crank degrees on an aftermarket performance cam, not turning the engine over by hand checking relief with clay before final assembly and shagging your lump IS a an actual bodgefest best left for chimps. However cleaning up a head for a lowly 4 pot and checking it with a straight edge is fine. A headgasket can take up .1mm+, easy to check with a straight edge, a feeler gauge and a torch.

Meowwwww

[Rav335uk]

Smashing a cam in the wrong way, not checking the timing against crank degrees on an aftermarket performance cam, not turning the engine over by hand checking relief with clay before final assembly and shagging your lump IS a an actual bodgefest best left for chimps. However cleaning up a head for a lowly 4 pot and checking it with a straight edge is fine. A headgasket can take up .1mm+, easy to check with a straight edge, a feeler gauge and a torch.

Meowwwww

[Gert_8]

Ross, really no need to have ripped Simon13 a new one...!

[parakeats]

What do you mean 45mm fuel hose? They are 8mm ID hoses

http://www.realoem.com/bmw/enUS/showpar ... Id=13_1329

#16+17, they're about 45mm long, either that or I'm suddenly getting huge hoses ;) stealers want £17 each, while none of my local places have any

[ross_jsy]

They are 8mm ID fuel hose. Go buy a metre for a couple of quid from any motor factors and cut it to length

[parakeats]

Had to order online as my town doesn't have a good auto parts shop apparently... another question - can I reuse the locating dowels, I haven't taken them out yet but will do so to be able to sand it down a bit. Or does that depends on their shape when they're removed?

[Simon13]

Adding a torch to the skillz of a straight edge and sandpaper is still a bodge, either way! Regardless, this isnt sound advice from Ross. Getting the head refaced is. Do you know how many people will have laughed at this comment! Sandpaper really, its gold that pure gold.

parakeats you can reuse the locating dowels, you should be able to carefully rotate them out with some plyers, add a bit of cloth so they dont add bite marks. Should make cleaning the block face up a bit easier


I'll go and cry now my bum hurts

[ross_jsy]

No where near the amount of people who laughed at you for tow starting a car with a mis-timed cam

[Simon13]

yup

[parakeats]

Thanks Simon, I'll work on taking them out when it's not too cold in the garage...

There is also a machine shop a couple of miles from me that I'm going to take the head too. Even though I'd be okay with risking not getting it done (and get the head done next time it blows if it does), atleast this way I can blame someone else but myself when it doesn't work after

[e30Passion]

OEM headgaskets are only from Goetze.

[reggid]

if youre going to use sandpaper on the head you are FAR better off putting (taping or gluing) the paper (multiple sheets if you cant get a roll) onto a flat surface (machine bench, thick bit of glass, old granite bench top etc and the sliding the head on top of it, the weight gives you better stability applies the pressure to right areas better. 1200 seems a bit too fine to be correcting flatness though.