Radiator replace do i take off/unlosen engine mounts on top to remove radiator8 deville northstar?

The most common overheating problem with the Northstar engine is a blocked purge line(small hose).The purge line is designed to purge air out of the cooling system.
There is a small diameter hose coming from near the top of the coolant tank (not the cap) ,this is the purge line.
With the engine idling,pull the purge line from the tank,if there is no coolant flow from this small hose,it is blocked and this will cause overheating.
If the hose is clear, check for blockage at the nipple on the tank.Or trace the hose back until you find the blockage.
The hose goes in to the engine to a crossover and comes out the other side close to the thermostat housing,the blockage may be there.
If you still wish to replace the stat...
The thermostat in the northstar engine is located at the bottom radiator hose (unlike most conventional cooling systems), the hose connects into the housing where you will also find the water pump.

You will need to remove the air filter housing and air duct to gain easy access to the thermostat.

Remove the hose from the housing,then remove the two bolts on the flange,the thermostat can then be pulled out.

Take note of the orientation of the thermostat as you remove it.

The thermostat in the Northstar engine is a dual action device.
One end of the stem is the Thermostat(obviously) and at the other end is a spring loaded pressure valve(the thinner end).
Make sure the thermostat end is nearest the rubber hose and the pressure valve end is in towards the engine.

Coolant should be mixed in most cases to a 50% concentration, meaning one gallon of undiluted coolant will provide two gallons of diluted coolant. Most engines will hold 2-3 gallons of coolant mix. I normally purchase two gallons of undiluted coolant. I pour the first gallon of undiluted coolant into the radiator, then fill the empty bottle with water and add that to the radiator as well to make it a 50% mix.. Then, I pour half the second bottle of undiluted coolant into the empty coolant bottle, and then top both off with water to make two gallons of 50% mix. I then add coolant to the radiator as needed until full, keeping the remainder for topping off later as air purges itself form the system.

This will violate local emission laws to install and older engine model year.

GM Cadillac Deville Fleetwood ELD Seville
1990-1998

Alternator - Removal and Installation - 4.6L Engine Except Seville

1. Disconnect the negative battery cable.

2. Remove the cover from the headlamps and radiator shroud.

3. Remove the air cleaner, if necessary.

4. Disconnect the left engine torque strut from the radiator support.

5. Disconnect the upper trans oil cooler line from the trans cooler.

6. Remove the right cooling fan and the left cooling fan.

7. Remove the serpentine belt from the generator pulley.

8. Remove the bolt from the front top of the generator, and the bolt from the lower front of the generator.

9. Detach the harness connector and output cable from the generator.

NOTE
The bolt nearest the exhaust manifold cannot be removed from the bracket but can be backed out to allow for removal of the generator.

10. Removal the A/C splash shield from the cradle, and the access panel from the bottom side of the radiator support.

11. Disconnect the engine harness from the cradle.

NOTE
The generator can be moved out away from the engine and removed from the bottom side of the engine compartment.

12. Connect the negative battery cable.

To install:

13. Install the generator to mounting with the two bolts to the rear of the generator. Hand tighten the bolts.

14. Connect the engine harness clip to the cradle.

15. Install the access panel to the lower radiator support. Install the A/C splash shield to the cradle.

16. Attach the harness connector and output cable to the generator.

17. Tighten the rear mounting bolts to 36 ft. lbs. (47 Nm). The output cable to 15 ft. lbs. (20 Nm).

18. Install the bolt to the lower front of the generator and tighten to 36 ft. lbs. (47 Nm). Install the bolt to the top front of the generator and tighten to 36 ft. lbs. (47 Nm).

19. Rotate the drive belt tensioner and install the drive belt around the generator pulley. Inspect for correct alignment of the belt with all the accessory pulleys.

20. Install the left cooling fan, and then the right.

21. Attach the upper trans oil cooler line to the trans cooler.

22. Install the left engine torque strut.

23. If the air cleaner was removed, install it now.

24. Replace the cover from the headlamps and radiator shroud.

25. Connect the negative battery cable.



Fig. 1 Alternator mounting-4.6L Northstar engine




Fig. 2 Component view of the generator and electrical connector




Fig. 3 Remove the top retaining bolt for the alternator




Fig. 4 Loosen the lower mounting bolt




Fig. 5 Remove the protective cap to gain access to the electrical connectors




Fig. 6 Removing the retaining nut that holds the battery cable to the alternator





Fig. 7 Back the bolt on the rear of the alternator out as far as possible and the unit can be removed from the mounting




Fig. 8 Pull the lower mounting bolt from the generator




Fig. 9 With the cable removed, attempt to bring the alternator through the allotted opening





Fig. 10 - Rotate the generator, if it aids the removal




Fig. 11 - Rotating the generator nose down . . .




Fig.12 . . . seemed to be the only way to extract it from the mounting

Assuming you have the Northstar engine.....

The thermostat in the northstar engine is located at the bottom radiator hose (unlike most conventional cooling systems), the hose connects into the housing where you will also find the water pump.

You will need to remove the air filter housing and air duct to gain easy access to the thermostat.

Remove the hose from the housing,then remove the two bolts on the flange,the thermostat can then be pulled out.

Take note of the orientation of the thermostat as you remove it.

The thermostat in the Northstar engine is a duel action device.
One end of the stem is the Thermostat(obviously) and at the other end is a spring loaded pressure valve(the thinner end).
Make sure the thermostat end is nearest the rubber hose and the pressure valve end is in towards the engine.

Don't forget the new gasket when you install your new stat, you may have to order this separately.

There is no radiator cap.The only cap is on the purge tank and these are quite cheap to buy and easy to replace.

The normal operating temperature for the Northstar engine is around 210 degrees.
The fans will not come on until the temp hits 225 degrees.

The thermostat in the northstar engine is located at the bottom radiator hose (unlike most conventional cooling systems).

The most common overheating problem with the Northstar engine is a blocked purge line(small hose).The purge line is designed to purge air out of the cooling system.
There is a small diameter hose coming from near the top of the coolant tank (not the cap) ,this is the purge line.
With the engine idling,pull the purge line from the tank,if there is no coolant flow from this small hose,it is blocked and this will cause overheating.If the hose is clear, check for blockage at the nipple on the tank.Or trace the hose back until you find the blockage.The hose goes in to the engine to a crossover and comes out the other side to near the thermostat housing,the blockage may be there.

If the other end of your purge line is not connected to anything then that is the problem......it must be reconnected otherwise the cooling system is not pressurized.

Assuming you have the Northstar engine....

The thermostat in the northstar engine is located at the bottom radiator hose (unlike most conventional cooling systems), the hose connects into the housing where you will also find the water pump.
Remove the hose from the housing,then remove the two bolts on the flange,the thermostat can then be pulled out.
Take note of the orientation of the thermostat as you remove it.
Don't forget the new gasket when you install your new stat.

Hi,
The thermostat is located in a housing attached to your engine, where the top radiator hose is connected to that housing.
I hope this helps...

4.6 Northstar V8. It is located on the rear of engine (driver side) in front. It is 1n the the waterpump housing cover. Remove airbox and intake tube and bottom radiator hose. 2 bolts(believe 10mm) on thermo housing. These systems are a lil finiky about air pockets....so fill slowly and let run at idle until operating temp and let cool and chk level.....fill as needed and repeat if needed.

There is a plate under the car on passenger side. Remove this plate and you will be able to see the alternator. I think it has three bolts