Comments on: Northstar Waterpump Replacement – Mechanics Tools

By: Erick

Erick — Sun, 28 Feb 2010 12:48:05 +0000

Question??? In my attempts to remove the water pump manifild to get to the water pump…(don’t ask as it is a long story) I removed the throttle body. I inspected the intake manifold and saw a pretty large build-up of oily residue and puddles of liquid setting on the bottom of the intake runners. Is this normal? Should I remove the intake manifold and clean it? If so what do you reccomend I use to clean the residue. What is causing the puddles?

By: Erick

Erick — Sun, 28 Feb 2010 12:41:41 +0000

I wish I found this web blog a couple of weeks ago because I would already be done repairing a coolant leak around the waterpump housing. I just ordered the socket tool to remove the water pump and look forward to finishing the job.

By: dennisb - Auto Tool Sales

dennisb - Auto Tool Sales — Thu, 18 Feb 2010 02:02:41 +0000

Paul, thanks for the clarification. It’s been awhile since I’ve changed one.

By: Paul

Paul — Wed, 17 Feb 2010 20:28:15 +0000

The water pump on the northstar engine has reverse threads. tighten to the left…loosen to the right or clockwise

By: tim

tim — Thu, 11 Feb 2010 16:06:06 +0000

im doing mine right now, update u guys later

By: dennisb - Auto Tool Sales

dennisb - Auto Tool Sales — Wed, 23 Sep 2009 10:19:29 +0000

Lee, If an impact gun is not available for removing the belt pulley bolt, then holding the nose of the pulley may be needed to break the bolt loose. It's been awhile since I've personally changed one of these water pumps, but the tangs on the water pump indicates that you would loosen it to the left (counter-clockwise). If you need further assistance from a Cadillac tech feel free to visit our car qusetions & answers page, usually there's a technician available that specializes in different makes.

By: lee

lee — Wed, 23 Sep 2009 01:16:51 +0000

Bought the tool for changing the water pump. How do you hold the belt drive pulley (lock it up) for the water pump so you can apply pressure to break free the impeller assembly? Also what way is it threaded, right or left? Don’t know when I am turning the water pump too lif I am tightening or loosening it?

By: dennisb - Auto Tool Sales

dennisb - Auto Tool Sales — Sat, 05 Sep 2009 18:43:39 +0000

Frank, Usually the water pump would leak, have a bearing start to bind, or lock up indicating it’s bad. The impeller can sometimes erode or come off the shaft altogether which would keep it from pumping. For test purposes, I would take the upper radiator hose loose (from the radiator) and stuff a shop rag in the radiator connection port. While keeping the radiator full and running the engine, (when the thermostat is opened) as long as it is pumping water out of the hose, the pump is working. (I used to flush cooling systems that way back in the 1980’s and 90’s) If water doesn’t pump out of the hose and the temperature starts to show the engine is overheating, the pump’s impeller could be off the shaft or eroded.

By: frank

frank — Sat, 05 Sep 2009 17:03:09 +0000

2000 northstar pump does not leak and turns with smooth rotation 175,000 miles do you think pump is bad.

By: dennisb - Auto Tool Sales

dennisb - Auto Tool Sales — Wed, 06 May 2009 11:05:08 +0000

Gary, The dealer may be able to order just the waterpump o-ring, but I would recommend replacing the water pump (which comes with a new o-ring). The labor involved in my opinion is too much to just replace the o-ring.