I just bought my first caddy 84 sadan deville with only 51000 miles from first owner for 450$$ i love it her late husband who took great care of it all the records in the glove box but it has not been cranked in over a year is there anything i should do before i start it i want to bring it home but dont want to mess anything up please help i love this forum i looked at all the info on the 4.1motor here thanks for your help
One thing that I would recommend you do is stop by a GM dealer on the way to get the car and pick up two quarts of GM Engine Oil Supplement (EOS). EOS is very heavily fortified with the anti-wear additive ZDP. Something not available in any of the aftermarket additives. Pour one can of the EOS into the engine before starting it. Don't worry about overfilling the oil at this point. Actually, overfillling it slightly will probably be beneficial for the first start up to get extra splash oiling to the cam and distributor gear.
The EOS in the oil will help guard against any wear or scuffing or scoring or parts during the initial startup. After sitting that long much of the oil will have drained off of moving parts so there will be some metal to metal contact in local areas. No way to avoid it but the ZDP will help and scuffs or scoring to "heal" as it will prevent further wear once oil reaches the areas.
Get it started ASAP. Don't crank and crank and crank. And don't pull the coil wire and crank to get oil pressure first. Just start it up. Cranking and cranking will put wear on the cam and lifters. You want it to start as fast as possible with the EOS antiwear protection in the oil.
Get it home and change the oil and filter and put the second can of EOS into the oil fill. For the same reasons. In case there was any wear, scuffing/scoring or corrosion on critical surfaces the EOS will help prevent wear more than plain oil. Don't be tempted to use any other aftermarket oil additives or anything. Just fresh oil and the EOS. EOS is relatively expensive because the ZDP additive is expensive - which is why aftermarket additives don't contain ZDP in sufficient concentration to do anything worthwhile.
It is critical to drain and refill the cooling system with fresh 50/50 coolant/distilled water. Use the conventional green, silicated coolant. While you are at the GM dealer getting the EOS, get a package of the GM Coolant Supplement pellets also. Install the coolant supplement pellets into the radiator when you refill the system. This is mandatory. The HT4100 engine could seep coolant internally which would contaminate the oil and destroy the engine. The coolant supplement pellets (at least 6 pellets should be installed) or sealer will prevent this.
Definitely pick up the quarts of EOS then. It really is a well developed and tested product and is one of the best assembly lubes around for putting together a new engine or protecting an engine after a repair in case something is not quite right.