Zone collective, Engine timing alpina e46

[Simon13]

I've been rebuilding my e46 B3 engine between changing nappies as of late and have come a bit stuck!

Now the engine itself is based on the S52 motor which is the US spec M3. So its basically the same as an M52 single vanos

Now I've just been having a play with timing the bottom end to TDC which is where I've become a little unsure




All manuals state to lock the flywheel/crank. Like I've done here with the actual bmw tool which really locks it. But as you can see the no.6 piston is not at the top of the bore?

The ring gear only fits one way on the back of the crank? i'm pretty sure you have the rounded edge of the ring gear towards the block.

But i'm pretty sure if you did this on m52's or normal s52's the piston is at TDC? As no.1 and 6 come up together.





This is the bmw timing mark, with alpinas own virbration damper on the front. The crank sensor is located at the back of the block on these with the ring gear on a crank web.

But theres a notch in the vibration damper and if you line it up with the bmw timing mark, hey presto no.1 is at TDC.

So now i'm a little I know not many have played with these but the collective know more than I.

I'm a little hesistant to bolt the head on and go time it up just yet as the gasket is £424 plus vat and i'm not buying another! I think myself that the later picture is the way to go and the locking the crank is wrong for some reason on this. Why I don't know. The cams can't be that hairy?! they are both alpina spec cams

all help appreciated!

[pacerpete]

Give Crouch a call. He will have done more than most.

[DanThe]

I never use the flywheel tool on M52's, always use TDC and its always been the way. Why it should be any different I dont know, but looking at the cams should tell you where the pistons need to be.

[Simon13]

I've rang crouch, but his receptionist keeps fobbing me off. Hes asked about when can I do brickwall! I said he rings me. i'll keep pestering

I've not saved his mobile Pete like a fool

[pacerpete]

lots of dial gauge/ trowel action needed. Crouch will call you shortly.

[daimlerman]

Still got the old h/g,Simon?

Thinking that you could dummy-build and turn the thing by hand to check for clearance,maybe?

[Simon13]

Phil has rang and confirmed I was on the right track.

That old hole is just that any old hole, Alpina don't use that method to time the 3.3 and 3.4 engines from the rear with the pin

Ideally a dial guage and then try and lock it up is my plan of action. A call to my dad is on the cards

[Andyboy]

You have to careful using the flywheel locking pin on autos as it's very easy to get the pin in the wrong hole. Time it up on the front pulley, job done.

It'd be interesting to get a B3 engine wiring diagram to see how they got a single vanos mill to work in a 46. Does it have a proper throttle body or fly by night wrongness?

[Simon13]

its fly by wire Andy, I've thought that aswell. Phil is a gold mine, I expect there can't be many in Europe who have fixed more of these engines than him




So Phil says at alpina they use some special tool that fits in here the M52 crank sensor slot, like a 13mm socket. With a nib on it in the middle and it locks the vibration damper at tdc and off they go. I don't have this but lining this mark up in the middle of the socket is as good as TDC rocking the crank back and forth. So I know i'm in the right place




This is the piston at the TDC height, I need to get a DTI guage to do it the "engine builders" way.

So really I can bolt the head down now and fit the cams and lock them into TDC and go from there with the DTI and fit the main chain.

[powelly]

Does something sit in that notch on the vibration damper, if you gave me some dimensions I could knock at work on the lathe, and then mill the nib in no time. If you gave me the vibration damper and the external dimension of that socket it would be easy,

[DanThe]

If your going to go to the trouble of perfecting the TDC its much easier to do it with the head off, you can then chisel a new mark on the pulley/block before fitting the head

[Simon13]

but you can still do that with a DTI guage as you measure the stroke with the dti down the spark plug hole with the head bolted on.

I'll ring phil in the morning to check what I think is right and go from there.

I'd like to say I won't be doing this kind of job again but that might be lying!

[DanThe]

Yes you can but you need an extra long pointer and have to faff about getting the base to sit on the head, you will do it in a tenth of the time with the head off

[Simon13]

i'm in no hurry, I need to order some new bits on Phils advice

rebuilds always take a while

[Andyboy]

Get the TDC mark sorted, then turn the crank slightly so the slugs are down the bores before fitting the head. Depends if you fit the head with the cams and valves open. Then return to TDC with the cams set with the locking tool and fit the chain.

[Simon13]

I used this and marked it up




like this and i'm happy the in the middle of the lines is exactly TDC. The lines either side show far/degrees the piston stays at TDC




i'm pretty sure if you turned a bit of steel dowel down in the lathe and machined a slot in here with a nib on the end to lock the vibration damper that would be very close to the tool alpina used at the factory when building these

I'm happy its right so I've bolted the head on and fitted the exhaust cam. I'm just waiting on some new vanos bits and chain guides/tensioner to turn up to finish the job.

[Simon13]

Engine is back in and running chomos. Going to be epic once its run in.

[e30topless]

well done si job done ? must be time to get back on the C2