Cadillac Northstar advice needed (insurance, car payments, gaskets, sedan)

[don1945]

My Sons and I build hot rods but when it comes to fuel injected, computerized engines I am not all that swift. My daily driver is a 98 Cadillac Deville with the Northstar engine. It has been a great car and runs and looks nice but is getting some age on it, so I decided to buy a lower mileage one, but about the same year model as I like mine so much.

I found a super clean 99 Deville but it evidently overheated and the oil pan is full of water and oil mixture. Rather than rebuild the engine that is in it I started looking for a low mileage engine, possibly from a wrecked car. Today I drove 200 miles and bought the proverbial old mans car, a 98 Deville that has 51,000 miles on it, but it was hit on the front left corner and totaled out by the insurance company. I have checked all the fluids, they are perfectly clean, and the engine was not touched in the accident. I drove it around tonight and everything works and the motor purrs like a brand new car. The engine is actually shiny and the bottom side is dry as a bone.

So, I am going to drop the engine and trans out of the bottom of the car and swap it into the other car that has the blown head gaskets. I plan on replacing certain parts that will be easier to do while the motor it out, such as the water pump, plugs, serpentine belt, and anything else I see that looks suspect when I get it out. Being a car builder I will also detail everything under the hood to make working on it easier and more pleasant.

My question is, what other parts should I change while it is out ? I understand there is a sensor on the front of the block that leaks over time, someone has suggested changing the engine mounts, and I wonder if there are other gaskets or parts that any of you can recommend be changed.

Thanks for any advice.

Don

[Vinsanity]

I assume you are aware that Northstars are notorious for blowing head gaskets?

[SD4020]

Pull all the harness and the PCM computer.

[don1945]

Originally Posted by Vinsanity

I assume you are aware that Northstars are notorious for blowing head gaskets?

Yep, I am, but I have owned two and have put over 250,000 miles on them total with no problems other than normal maintenance and normal parts replacement. What seems to kill them is if they over heat.

Don

[SloRoller]

I own a 1998 Olds Aurora, which has Oldsmobile's version of the NorthStar. I got 331,700 miles out of the original engine before it blew a head gasket. Truthfully, it overheated on me when a hose blew and lost all the coolant. There was no place to pull over for several miles. so that hurt the motor. Otherwise it was tired but working fine.

Because the body and interior are in great shape, and to get a similarly sized late model luxo-performance sedan costs way more than I am willing to or can pay, I had a new transmission and engine installed, got it painted, rebuilt the suspension, replaced the rack and pinion and all major mechanical parts. Back on the road for less than $18,000 with a 3 year 100,000 mile warranty. Car is paid for and I know the history of the vehicle. A late model sedan with anything close to the leg and head room, similarly appointed would be well over $30K...well out of my price range.

Since you have the engine out, I recommend you replace the following:

ALL rubber hoses
ALL sensors
Catalytic converter(s)
Injectors (if they are not performing properly)
Intake gaskets
Starter
Engine and transmission mounts (this is a bear if you try to do it with the engine installed...do it while the engine is out)

On the other hand, your used engine has relatively low mileage, so you may not need to go to the lengths I went, as my mileage was significantly higher.

At a minimum I would replace all the hard-to-reach sensors and all hoses and belts, the thermostat, and have the radiator cleaned and pressure tested.

Good luck.

[don1945]

Great advice, SloRoller, thanks. I tend to keep my cars a long time for the reasons you outlined.......I hate car payments and love the comfort and style of this particular model Caddy. Here in Florida it is easy to find older cars with extremely low mileage because of the older population here. I had an 84 Crown Vic that I bought about 10 years ago that had 50,000 miles on it. The 84 year old lady put new Michelins on it, drove it home, and never drove it for 4 years until I bought it.

I like you suggestions about the hoses and thermostat plus the motor mounts. Will do those too. There is that one sensor on the front of the engine that tends to leak oil after time, so it will get changed too. I am going to run injector cleaner through the system once I make the swap, but they seem to be ok now from the test drive we took last night.

Thanks again.

Don