Northstar water pump removal

[Ed Hall]

The water pump on my '93 Allante started to leak so this evening, I tried removing the old pump but it is too tight. First I tried using my electric impact wrench rated at 250 lbs of torque but after about 5 minutes of use, it died. I then used my Craftsman 1/2" drive and slipped over a 3 ft extension. The end of the extension must have moved about 10" when suddenly, the 1/2" drive snapped. Anyways, what to do? Yes, I'm turning it clockwise.

Maybe I need something like this.

http://www.harborfreight.com/cpi/ctaf/Disp...temnumber=92421

[caddypete]

Well at least you can get your broken tools replaced with no hassles, if that is any condolences.When a bolt won't budge spray it with a good penatrant, not WD40.let it sit, use a good wrench or socket (preferable 6 point) try to tighten the bolt, then loosen, then try again.

Don't go crazy on the bolt with torque, you think it's hard to get out now wait tilll the head is broke off. tap the bolt with a hammer a few times, try again, spay it with penatrant, go back to working on what else needs to be done, let it sit, eventually it will break loose. if not, get the torch

[KHE]

Ed,

You need an air impact wrench and it should come right out. I expierenced the same thing when helping a coworker replace a water pump on a 95 Aurora - the socket kept slipping, etc. and when I put my air impact wrench (550 ft-lbs reverse torque) on it, it came richt out.

[BodybyFisher]

I am beginning to see there is a difference between a sissy impact wrench like I have and a 550 ft lb brute. The other thing I believe is important is to make sure that proper air volume is available to the tool, I think I am choking my air tools with a 3/8 hose and numerous fittings and need to go to 1/2" and eliminate some fittings.

[KHE]

I am beginning to see there is a difference between a sissy impact wrench like I have and a 550 ft lb brute. The other thing I believe is important is to make sure that proper air volume is available to the tool, I think I am choking my air tools with a 3/8 hose and numerous fittings and need to go to 1/2" and eliminate some fittings.

Definitely spend the money for a good quality impact wrench - you will not regret it. Buy the wrench with the highest reverse torque you can afford. The 3/8" hose should be fine but it is the quick disconnects that choke off the supply - the only place you should have a quick disconnect is at the air tool itself.

[BodybyFisher]

I am beginning to see there is a difference between a sissy impact wrench like I have and a 550 ft lb brute. The other thing I believe is important is to make sure that proper air volume is available to the tool, I think I am choking my air tools with a 3/8 hose and numerous fittings and need to go to 1/2" and eliminate some fittings.

Definitely spend the money for a good quality impact wrench - you will not regret it. Buy the wrench with the highest reverse torque you can afford. The 3/8" hose should be fine but it is the quick disconnects that choke off the supply - the only place you should have a quick disconnect is at the air tool itself.

Thanks, I didn't realize that the reverse torque could differ I need to check mine. In the past I have had stuck bolts and it will just sit there in reverse chugging having no effect. I have had up to 3 quick disconnects in use I have not taken the time to solve this and need to.

[Ranger]

I am beginning to see there is a difference between a sissy impact wrench like I have and a 550 ft lb brute. The other thing I believe is important is to make sure that proper air volume is available to the tool, I think I am choking my air tools with a 3/8 hose and numerous fittings and need to go to 1/2" and eliminate some fittings.

Definitely spend the money for a good quality impact wrench - you will not regret it. Buy the wrench with the highest reverse torque you can afford. The 3/8" hose should be fine but it is the quick disconnects that choke off the supply - the only place you should have a quick disconnect is at the air tool itself.

I finally came to that conclusion about a year ago. My 250 was not cutting it. I bought a 650. Now I am loaded for bear. The 250 is for sale.

[MAC]

Great, just what I needed to hear--Another water pump removal nightmare. I'm about to go home and try to replace my water pump. I have a quality made socket but I'm not looking forward to this job. The first time I tried I was a bit cautious about applying too much torque to the socket. This time I'll resort to propane heat if all else fails. I'll heat the water pump tongs.

Anyway, Ed--Good Luck! I hope it all works out.

[Ed Hall]

I'm planning on taking some water along and driving my car tomorrow to the hobby shop where they have a big air impact wrench. They charge $1.80 per hour so I figure this is much cheaper than breaking all my tools .

[BodybyFisher]

I am beginning to see there is a difference between a sissy impact wrench like I have and a 550 ft lb brute. The other thing I believe is important is to make sure that proper air volume is available to the tool, I think I am choking my air tools with a 3/8 hose and numerous fittings and need to go to 1/2" and eliminate some fittings.

Definitely spend the money for a good quality impact wrench - you will not regret it. Buy the wrench with the highest reverse torque you can afford. The 3/8" hose should be fine but it is the quick disconnects that choke off the supply - the only place you should have a quick disconnect is at the air tool itself.

I finally came to that conclusion about a year ago. My 250 was not cutting it. I bought a 650. Now I am loaded for bear. The 250 is for sale.

MAC you love heating stuff! Earlier in the week you were heating a caliper! I wish I was more comfortable with heating stuff. I recall an experience I had years ago. I broke an exhaust stud off and exhaust manifold. I took it to a machine shop, he heated the manifold red, and twisted the stud out like it was butter.. I think too much, will I make the manifold brittle, etc..

[MAC]

MAC you love heating stuff! Earlier in the week you were heating a caliper! I wish I was more comfortable with heating stuff. I recall an experience I had years ago. I broke an exhaust stud off and exhaust manifold. I took it to a machine shop, he heated the manifold red, and twisted the stud out like it was butter.. I think too much, will I make the manifold brittle, etc..

You got it! I’m not going to fool around when all I have to do is apply some heat. As long as I can do it safely without damaging something I always consider heat as an option. I will be cautious, however, not to overheat the aluminum. I figure some moderate heat applied in a circular motion around the water pump should be enough to break the bond and make the tongs more pliable. But I will give it another try or two without heat.

[Ranger]

Mac,

I would be concerned about the pump housing gaskets where they mate to the block. I would also be very concerend about the "O" ring pump seal. If you melt that and turn it to goo you may have a tough time getting the new one to seal.

If I recall correctly, this problem seems to occure on green coolant engines. It is calcium build up and someone once mentioned using someting like CLR as a penetrant to loosen it up. Anyone remember this? I wouldn't think it would hurt to try.

[Ed Hall]

Yes, my '93 Allante had green coolant in it. It is also 14 years old but only 63k miles.

[Ed Hall]

I tried again this evening using a stronger breaker bar and ended up breaking my water pump removal tool. Two cogs broke so now I am stuck. It was special ordered and took me a month to get this tool.

Next question, how about going to the junkyard and buying the whole waterpump and the housing. I really need to get this thing running soon.

[Ranger]

Ed,

Just out of curiousity was that the stamped steel tool or the machined one?

[BodybyFisher]

Very true Ranger. I see a wide range of prices on these sockets, we had someone else destroy a stamped unit (assuming this was a stamped unit).

I would buy a high quality socket and use a high torque impact wrench on it. As someone mentioned before it needs to be cracked loose, providing low torque is doing little.

I would not go the route of replacing the housing crossover until I got a good impact wrench on it

[Ed Hall]

How do I tell? The brand was Astro Pneumatic. It was thicker at one end and tapered down in thickness where the cogs were.

What a headache. Probably should have had the dealer do this job. I have eaten up about $80 worth of tools. Now I'm stuck with a bunch of garbage tools.

[Ranger]

I think Astro Pneumatic are stamped. A Snap-On, Mac or Kentmoore will run close to $100. Here is a pic of one I made from Snap-On specs http://www.geocities.com/grandolfo. I think Bruce has a good machined one for rent.

[KHE]

Ed,

Dealers will typically charge in the $500 price range to do a Northstar water pump. I found that out about 5 years ago with my '96 so I did the job myself. I rented the socket from Bruce - it was a Snap-On socket and was very durable. Mine came right out with a 1/2" breaker bar but my cooling system was using DexCool so the cartridge was not corroded in place.

The most neglected cooling system I have EVER seen was a coworker's Aurora that I mentioned earlier. The coolant was grey.... I'm sure it had never been changed... It was so corroded that the cheap stamped socket would deform and slip off. I put my impact wrench on it and it came right out.

Buy/borrow/rent a good air impact wrench and rent the socket from Bruce and you should be able to remove the pump. Replacing the water pump crossover is a big PITA.... plus you'll need four new gaskets and you won't know the conditon of the used pump.

[Ed Hall]

I think Astro Pneumatic are stamped. A Snap-On, Mac or Kentmoore will run close to $100. Here is a pic of one I made from Snap-On specs http://www.geocities.com/grandolfo. I think Bruce has a good machined one for rent.

The tool I have looks about as strong as the one you made. It still has 4 more teeth left so there's a chance I might be able to get it off with a heavy duty impact wrench.

Ed,

Dealers will typically charge in the $500 price range to do a Northstar water pump.

The high price must be due to all the broken tools this job causes. It takes me less than 15 minutes to gain access to the water pump and if this water pump would just release, I could do the job in less than an hour.

[franey]

YOU might think this is crazy , but i have seen it work several times before on ones that would not come out, TURN IT THE OPPOSITE WAY, the ears that lock it in are short, they will bend backwards and then the rest will ride over the top of the housing and come out. Before YOU do this take a chisel and go around the pump and thump it with a hammer , tends to break it lose. Use PB blaster and let it soak overnight and then spray it down again.

[MAC]

I think Astro Pneumatic are stamped. A Snap-On, Mac or Kentmoore will run close to $100. Here is a pic of one I made from Snap-On specs http://www.geocities.com/grandolfo. I think Bruce has a good machined one for rent.

The one I bought at Advance Auto for $25.00 is a two-piece. The top is heavy duty metal and was welded to the body/cogs. If anyone wants to see a pic let me know.

[The Fred]

You'd be surprised what a good penetrating oil will do.

Wd-40 is junk it is good for attracting dust.

Have you tried some carefully applied heat?

Turning the opposite way DOES work just don't go over of a board!!

[MAC]

I tried again this evening using a stronger breaker bar and ended up breaking my water pump removal tool. Two cogs broke so now I am stuck. It was special ordered and took me a month to get this tool.

Next question, how about going to the junkyard and buying the whole waterpump and the housing. I really need to get this thing running soon.

WOW Ed, I'm sorry to hear about the problems.

After everything I've heard about removing these water pumps I think I'll see if I can find a decent but not so expensive 12V compressor and 400 lbs./ft impact wrench.

[franey]

Remember everybody, a bigger impact wrench will not matter if you do not have the air volume to carry it. You can go up in impact and still not remove the object you are trying to if you do not have enough air volume to push the hammer with enough power. IF you are running a bigger impact you had better have a bigger tank or you might not get the results you anticipated. IT is not that the 400 lb. impact could not remove it , you just did not have enough air volume.