Waterpump problems...

**TheWhiteKnight** · 06-18-2008, 12:34 PM

Greetings folks,

I have a 2004 trailblazer which I have recently replaced the water pump on. After a few weeks, the pump for some strange reason loosened from the block and backed out. Are there any torque specs on the puny bolts that GM has holding the water pump, fan clutch, and fan to the block? I tightened them down until I was grunting (which is pretty tight) but I'm a little leery to put that much "oomph" on those bolts because they look like they would snap off pretty easy.

The reason that I ask is it looks like the bolts are starting to back off again. I don't want this to be a chronic problem, but without the torque specs, I'm at a loss.

Can anyone toss up some (*correct*) specs for me or point me in the right direction?

Thanks in advance for anything / everything that can be provided.

- Josh

**Crawdaddy** · 06-18-2008, 12:48 PM

locktite? I'm not sure if you'd want to put it on those bolts, so wait for confirmation from another member before following my suggestion....

**TheWhiteKnight** · 06-19-2008, 09:20 AM

Originally Posted by Crawdaddy

locktite? I'm not sure if you'd want to put it on those bolts, so wait for confirmation from another member before following my suggestion....

Thanks Crawdad, I was hesitant to put locktite on it. I've got 2 different grades of it (Quad 4 racing engines require it with ARP Head stud kits)

Maybe some lock washers? I have no idea what to do in this case. I've never had this happen before and it is a little strange. It really almost seems like I didn't put the water pump bolts in with enough torque. Hopefully I can get an answer by this weekend before I look at it again. Gotta do tie-rods on the Cad first.

**Crawdaddy** · 06-19-2008, 09:23 AM

all I have to say is don't overdo it, especially if your heads are aluminum (but you knew that already...). It would suck big-time to have to yank the heads because you stripped the threads in the heads and block.

**Pete95Sierra** · 06-19-2008, 09:45 AM

i dont think it would hurt to use loctite. did you use copper permatex to make the gasket?? if you do you are going to get some permatex on the bolts by just screwing them in anyway and that will hod them

**TheWhiteKnight** · 06-20-2008, 08:11 PM

Originally Posted by Pete95Sierra

i dont think it would hurt to use loctite. did you use copper permatex to make the gasket?? if you do you are going to get some permatex on the bolts by just screwing them in anyway and that will hod them

I didn't use copper permatex to make it, I used water housing gasket sealer on a metal impregnated silicon gasket. I can pull the bolts back out and re-line them with some loctite (blue or red), that's about an hours worth of time.

**TheWhiteKnight** · 09-05-2009, 04:00 PM

Ugh, the problem is back.....

Well there for a while, I had the water pump problem solved. It seems that poor engineering from GM or a cheap autozone replacement waterpump was to blame (probably a combination of both).

I don't know who's bright idea it was to have the weight of the fan clutch, and the fan itself on the end of the water pump, but it seemed to have worn out the bearings on the pump causing a wobble in the water pump shaft.

Time to replace it once again.

I cannot remember how to do this. I fished the pump and everything up through, what is the bolt that holds the water pump to the clutch? regular or reverse thread?

Thanks in advance!