Preparation for attaching gearbox

[gudgeon]

I'm really agonising over what to do before I bolt the gearbox up to my M50. Obviously most recommend a new clutch, what about the following:

Sump gasket: I've got a steel one, but do I need a new one?
Rear crank seal: Anyone found leaks in these?
Gearbox input shaft seal: Again, is it a troublespot?

Anything else?
EDIT: I know about the spigot bearing and clutch release bearing.

[E30BeemerLad]

sump gasket is a must, even if yours is holding up alright as it would mean the whole lot coming out again in the event it did spring a leak.

The crank and gearbox seals are not as common to cause problems so if they look nice & dry around those parts, they are probably OK.

[daimlerman]

Must confess that I walloped my M50 in with nothing more than a spigot bearing and a new clutch,it was oil-tight in the E34 and it's remained oil-tight in the touring!

I would suggest that you renew the gearbox linkage and bushes/wearpoints and fit a Z3 1.9 gearstick whilst the lot is on the garage floor...much easier to fit and makes so much difference to the 'feel' of the conversion!

[DanThe]

If the rear seal looks oil tight then leave it, I fitted a new seal to the 3 litre I built and it hasnt stopped leaking..

[nickso]

sheesh, dont say that, i changed mine when i put the 'box back on.

[gudgeon]

Thanks for all the advice guys.

Reckon I'll leave the rear seal as it's expensive and Dan seems to think replacing it doesn't guarantee no leaks anyway.

Gearbox I'll take a closer look at. It's so filthy in there it's hard to tell what's been leaking.

Sump gasket I guess I'll do on advice. Thing about this one is that even if I support the front subframe, undo the mounts and lift the car up, I'll still have difficulty replacing the sump gasket.

With regards sump gasket, I've heard that a bit of hylomar on each corner is a good idea, any views? On the sump or on the block or on both?

[E30BeemerLad]

So have you already got the engine in the car? I'd consider removing the engine to make life a hell of a lot easier for both fitting the sump gasket but also bolting the gearbox up.

[gudgeon]

No, sorry to confuse, it's NOT in the car yet, but sump will be a bitch when it is, even worse than clutch I reckon, 'cos gearbox has to come off and subframe probably needs separating from engine (I'm guessing).

EDIT: Actually you raise an interesting point though. I'd considered getting the engine running first before spending money on extra bits, 'cos I've never seen it running. It MIGHT be a good idea to get it going without a gbox, knowing that it will always need to come out again anyway.

[E30BeemerLad]

yes indeed, this is why it is recommended to do the sump gasket even when they look dry as it is a sad job trying to do this with the engine in the bay (either needing the engine to be supported from above and the whole subframe dropped down out the way or needing the engine to be removed)

gearbox best attached before putting engine in the car as the top bell housing bolts are pretty much a no-go area when the engine is in the car

[Jozi]

Sorry to go off topic, where about are the crank shaft seals?

[Sjoerd320i]

Not far from the crank shaft I believe so...

[Jozi]

Grapjas

Are they where the flywheel bolts on to the crank?

Reason I was asking was because when I was lifting the engine all the oil came pooring out through the flywheel bolt holes, wasn't sure if that was normal or not?

[magpie]

changing the sump gasket while the engine is out is a must,and very much rule of thumb

got mine for about £35 from bmw

[Jozi]

I was hoping that might have been the case, didn't know where the oil was leaking from when i was lifting it with the crane, made a nice mess on the drive to