M30 engine rebuild advice neede

[TheMoose]

Hi Fellas!

Which parts do you guys recomend when rebuilding a naturally-aspirated M30 3.3 engine?
I am asking for the real deal i.e. pistons, gaskets, oil pumps. Everything.
How much will one pay for the parts alone?
New to the forum and really want my M30 back on the road.

[maggspower]

Hi there, and welcome.

This is really hard to say without seeing the engine, first of all why are you rebuilding it? What is wrong with the engine? may be its just the top end that needs doing, I have heared that the bottom end of these are good for some intergalactic mileages

Should it need a fill rebuild the things that will definatly need to be renewed; crank shell bearings, piston rings, bores re-honed, gaskets, oil seals, oil pump, water pump, cam belt ect............. and thats without looking at the head.

The problems start when you have to work out which parts can be reused, things like, have the pistons gone oval, do the crank journals need a regrind, are the valve guides ok (exhaust side probably not).

Building engines is not a cheap hobby, you can save money by knowing which parts can be re used but that comes with experience.

Having said that it is very rewarding when you hear it bursting in to life for the first time

A compression/leak down test would be a good place to start if the engine is still in a car.

[TheMoose]

Thanks for the prompt reply.
Basically, One piston and valve decided to kiss each other. I was also looking at changing the following:
> -The bust Piston
> -Piston rings
> -Mans bearings 20
> -Big end bearings
> -Exhaust valve
> -Intake valve
> -Oil pump
> -Complete gasket
> -Top gasket
> -Timing chain
> -Oil pump chain

As you know that BMW parts don't come cheap, I was looking at saving a bit by using other good products.
Oh: The engine is the 3.3 from the 733i. Ofcourse, a gasflow and port job will also be done.

[maggspower]

I must admit the m30 engine is not my specialist subject, but I do know that havent heared of that many being 3.3L. The 3.5 is the more common swap talked about, have you considered getting a new second hand engine?

http://cgi.ebay.co.uk/E24-635CSI-3-5-EN ... 240%3A1318

Thats not alot of dosh and an extra 200cc. Infact, sod it I think I'll buy it

[TheMoose]

Getting a second hand engine is out of the question as the car was built by Alpina and the engine is the original one. Just to maintane the prestige of the car, I want to rather rebuild it.

[MJJ_ZX6RR]

Have you found the root cause of why the piston hit the valve? I'd be interested to know.

I think I would be adding the water pump and timing chain tensioners to that list also. Are you going to remove the crank and check for runout too?

Martin.

[TheMoose]

I must be honest MJJ_ZX6RR, I know very little about cars. Therefore, I will rely on my mechanic for the technical stuff. However, he did mention the need for a timing chain and tensioner as well as a revamped cooling system. I was just shocked by how expensive parts are from the BMW agents here in South Africa. Given the fact that I have also revamped the body, I thought that there could be a saving by rather importing some of the parts.
So the original question should have been: Where do you guys recommend I import the parts from?

[MJJ_ZX6RR]

Probably worth asking Cotswoldbmw on here, there is a whole forum for it. I know they are not keen on sending parts out of the country, but I am happy to have the parts posted to me and forward them onto you if you decide to go down that route.

Martin.