E30 Zone

Hi,
I have recently acquired a Marlin Sportster kit car, an impulse buy after one to many beers down the local pub. it is a complete rolling shell, though it has been an abandoned project for over ten years and never been on the road. Anyhow the purchase came with an engine and manual box from a mid eighties E23 7 series. It is the 3.5 ltr engine.
the previous owner said he ran the donor 7 series for six months or so before removing the engine and box and claims it ran well with the only issue being small puffs of blue smoke on the overrun, which usually means valve stem oil seals. I have the engine on an engine stand and plan to strip it over the next few weeks.
I only intend to replace the valve stem oil seals, head gasket and all other gaskets, and the water pump. Probably the clutch and clutch slave cylinder as well. I have not worked on an M30 before which is a bit different to the M42 and M25 engines, or maybe not ??
I don't have any plans to modify the engine, 218bhp and loads of torque is enough I think on a car weighing about half an E30.............


Questions; Are there any particular problems with changing the valve stem oil seals ? and can I reuse the cylinder heads bolts or do I have to replace these with new ones on re assembly.
I also have the original engine wiring loom and ECU and I am unsure on how best to connect this into the not yet fitted basic loom for the Marlin. Would it be as simple as connecting the engine loom, including the Ignition and fuel pump wiring, into the ECU via the original plug and then just providing a separate live feed to the ignition switch and the ECU from the main loom.
Anyone any ideas on how best to do this.

All constructive comments welcome
Thanks
Jim

There is a zone member who built/fitted an M20B28 to one of these, there are sure to be posts on here if you use the search function, he does have his own website too although I cant remember what its called

His name is martinclan:

http://www.e30zone.net/modules.php?name ... file&u=927

However, it could be worth checking that all the crankcase breather and vacuum hoses are clear and in good condition with no splits, etc. before you go stripping the engine down, as it could be just a perished hose that's causing the problem...

As above. I wouldn't get stuck into a rebuild without checking the basics first, and it's quite possible to change valve seals without removing a cylinder head. (Feed thin rope in through a spark plug hole, and then bring the piston up to hold the valves fully closed.)
Electrics wise, the engine loom is completely self contained, with a wire each to battery + and battery -, a green wire for ignition switched 12 volts +, a black/yellow wire for the starter motor signal, and a green/purple wire carrying 12 volts + back out for the fuel pump. Other wires are largely for communication between the instrument luster and the engine ECU, but the engine will run without them.

If you do remove the valve stems, do it carefully. A pair of valve stem pliers are preferable.

The reason I say this, I installed an m30 into my e30 and it did not run well. Then a few hundred miles in a rocker snapped. Upon removal of the head and valves, the valve where the rocker snapped had to be hammered out. It had clearly had the valve seals done as they were aftermarket, along with the head gasket. My theory is someone mullered them out with some pliers and crimped the top of the valve guide, causing it to jam.

Never reuse head bolts (with the exception of things like ARP's providing you check them with a stretch gauge). A set of headbolts cost me something like £20 so it's not like they are big money.

While the heads off, have a think about skimming the head 1mm to raise compression. It gives it a nice power and torque boost

Thanks for the replies Guys;
I checked out the crankcase breather, all the hoses for the engine were in a box, and it is indeed split, so I think I will just replace the hoses rather than change the valve stem oil seals. The engine appears to be in good condition, supposedly only covered 140 K miles, I took the sump and rocker cover off for a look and all seems well so I think I will just put it all back together and see how it runs when I eventually get to that stage.
I checked out the Martinclan site and there are a lot of useful posts on there: thanks.
mine is a wee bit different in that it has ben fitted with Ford Granada suspension, brakes and Diff, the only Beemer bits will be the engine and box. at some point I will have to have the rear of the BMW prop shaft altered to fit to the Ford Diff.
Apparently, though I have not confirmed this as yet, mine is an earlier model than Robins (Martinclan) and the rear suspension / subframe mountings were not designed for E30 parts, hence the Ford bits.
Thanks for the wiring advice Brian, I was hoping that this part would be relatively straightforward ........... !!
I'm still going through the boxes of bits and paperwork that came with the car and there are a few jobs to be done before Im ready to install the engine and box.
Thanks again
Jim