I have a 1987 740 GLE and this is the second time in about a month that I went to start my car--put in key & didn't turnover..the sound was there almost did-- so tried again & nothing, no sound at all, radio or anything. Last time was a snowy day, figured battery was dead, then tried in aftrernoon & started right up, haven't had problems since, today I tried to crank later 7 sounded like the sound when you try to crank a car when it's already on..screech!! If it makes any difference I have been told I need a harmonic balancer--I believe that's the name--the car makes a rattling noise frequently..PLease help, was thinking of getting battery but short on funds & want to make sure that is the right move, especially since it turns over after sitting a few hours..thanks!

The Harmonic Balancer (aka Crank Pulley) may be the cause of the "Screeeech" as well as the occasionally dead battery.

The pulley has an inner part that is keyed to (and rotates with) the crankshaft. It also has an outer part with V-grooves to drive the accessory belts.

The two parts are rubber-bonded together. Over time this rubber bond loses its grip, which can (intermittantly) cause the outer part to slip, resulting in—
1) Squealing noises
2) Failure to proprly drive accessories (including the Alternator, which may therefore fail to keep the battery charged).

It can also fail to drive the water pump adequately, leading to overheating, or the two parts may finally separate completely, with belts flying who knows where.

Check the 700/900FAQ for more info, how to check, replace, etc.
--
Bruce Young
'93 940-NA (current) — 240s (one V8) — 140s — 122s — since '63.

thanks for the reply, I put battery in & runs fine, realize it may be the result of thr "balancer" but don't have the funds to replace now, but hopefully sonn..thanks!