e34 3.5 engines...

[e30_singh]

what should i watch out for when hearing and listening to the engine?

I know the general ins and outs of engines and what sounds right and wrong. But maybe someone can teach me something i dont already know, as im going to look at a 3.5 engine over the weekend.

thanks

[Brianmoooore]

I'm not realy familiar with this engine, but AFAIK, it doesn't have any specific weak points.
Just look for blue smoke when started from cold and any odd noises or rattles that shouldn't be there.
Have a look at the dipstick. Thick, black, smelly oil is bad, new clean oil is suspicious, and no oil at all is very bad news.
Check the coolant for oil contamination, and look under the oil filler cap for excess mayonnaise.
Oil pressure light should come on with ignition, go out within half a second of starting and be never seen on again, even at idle on a fully hot engine.
Take cam cover off if you can and check the cam lobes for any wear ridges, spark plugs out for inspection.

[Andyboy]

Are you buying if for the engine to plop into an E30 or as a car to drive?

[DRIFTBOY]

Rattling top ends are fairly common on high mileage / neglected engines.

Can sometimes just need the valve clearances re-setting though, or worst case - the oil spray bar bolts can come loose (there was a mod for this using different bolts and washers) so starve the camshaft of oil.

Oil leaks down the right hand side of the timing cover are quite common and an easy fix if it's just the loose crank position sensor bracket top bolt.

Martin.

[Simon]

Moved to other BMW chat.

[casper8r]

Thick, black, smelly oil is bad, new clean oil is suspicious, and no oil at all is very bad news.

So basically it's a choice between bad, suspicious and very bad?

[Kos]

cam wear , cracked head due over heating are the only 2 things that i've known to go wrong

[DRIFTBOY]

A lumpy idle is often caused by a minor problem - perished / split breather, vacuum (which go to the underneath of the inlet manifold) or inlet pipes are common. Even a knackered oil filler cap seal will affect idle so check those first before walking away.

[casper8r]

I'm severely tempted to swap my car for a 535, I must stop reading these threads

[e30_singh]

the reason i was asking because i bought a 335i of someone and i wanted to make sure the engine was ok.

all im going to say is that a 335i is very nice!