Help with Water Pump replacement

[Droctrebor]

Ok this seemed easy enough. However things quickly came to a halt when I tried removing the fan from my old water pump.

I have a 1999 Astro van and the water pump needed replaced. I took out the old pump and started removing bolts etc... I am having a heck of a time (literally 3 hours of time) trying to get the fan removed. It appears to be bolted directly to the water pump via a huge nut (1" wrench is much too small to fit this bolt). Can anyone provide any suggestions for this please. Is this nut threaded opposite ? My main problem is obviously trying to get a good grip on it as the whole shaft turns and there is really nothing to grip to from the water pump side of the shaft. If anyone has any experience at this, please post a reply, you help is much appreciated.


Regards,
Bob

[GMMerlin]

there is a special 2 piece tool to remove the fan from the pump.

[rbritt]

Yes you do need a special tool. After much frustration trying to figure this thing out, it turns out to be this tool

http://www.autozone.com/servlet/UiBr...tch_wrench.jsp

That is marketed as a special tool for Fords. The job is much easier with this tool, and with the Autozone tool loan program it can be used for free,

[manny-man]

Originally Posted by Droctrebor

Ok this seemed easy enough. However things quickly came to a halt when I tried removing the fan from my old water pump.

I have a 1999 Astro van and the water pump needed replaced. I took out the old pump and started removing bolts etc... I am having a heck of a time (literally 3 hours of time) trying to get the fan removed. It appears to be bolted directly to the water pump via a huge nut (1" wrench is much too small to fit this bolt). Can anyone provide any suggestions for this please. Is this nut threaded opposite ? My main problem is obviously trying to get a good grip on it as the whole shaft turns and there is really nothing to grip to from the water pump side of the shaft. If anyone has any experience at this, please post a reply, you help is much appreciated.


Regards,
Bob

hello my name is manny and i also had a problem with that bolt if its not to late i took it to sear and they had a big enough wrench and they put the pully on a vise it came off quick . manny

[MisterWolf]

Originally Posted by rbritt

Yes you do need a special tool. After much frustration trying to figure this thing out, it turns out to be this tool

http://www.autozone.com/servlet/UiBr...tch_wrench.jsp

That is marketed as a special tool for Fords. The job is much easier with this tool, and with the Autozone tool loan program it can be used for free,

Thanks to you guys for posting this stuff. It had been awhile since I replaced a GM water pump...pre-THREADED days. In case someone else needs to know, I'll state what is obvious to me now - the 57mm wrench is used to hold the water pump pulley via the mounting bolts and the 35mm is used to remove/install the fan/clutch assembly, counter-clockwise to remove. Makes for an interesting challenge when the AutoZone loaner kit 35mm had been abused in a terrible way, such that it was unusable. In case you have a spare 1-1/4" open end wrench, it didn't take much to grind it up to approximately 1-1/2", which will do the job nicely.

[Jeffreytcole]

I wish I had read this before I replaced my water pump last year. I was able to get the fan off without a special tool after hours of frustration using a vise and a strap wrench and two friends....

[Roaster]

Originally Posted by Jeffreytcole

I wish I had read this before I replaced my water pump last year. I was able to get the fan off without a special tool after hours of frustration using a vise and a strap wrench and two friends....

Same thing I used a pipe wrench channel locks and a brass hammer and beat it ccw until it broke loose. I two whish I would of read this first. The chiltons book was no help.

[brcidd]

You guys remove the fan last? Sure would be hard to get to the water pump bolts- I take the shroud off- then go straight for the fan to get it out of the way- I use the Serpertine belt- add tension to the tensioner to hold the water pump from turning- then simply unscrew the fan- once it is out- then remove the 10mm nuts- and then take off the belt- then remove the water pump pulley- why make it hard- I have done 3 or 4 this way- no special tools needed- Just did my brother-in-laws '99 Yukon last week- in and hr and a half- including the drive to the parts store...

[gat1954]

Looking from the Bumper Front
Which way do you Turn the Single Large Bolt to remove the Large Fan with the Clutch...

Is this LEft Handed Threaded ???? IF this would be so, then you would Turn it Clockwise ??? Looking from the Front to Remove .... Correct or Incorrect....

Sure seems like a good IDea to Increase the Tension, on the Serpentine belt, to keep the Fan from Slipping

Gary

[Blue Bowtie]

The thread is a standard, right-hand thread. The water pump is reverse rotation, like most other late small block Chevy designs with poly-V belt setups (serpentine). I've used a 1-3/8" open end and a strap wrench around the pump sheave.

Do yourself a favor and apply antseize compound when you install the fan on the new pump.

[Blue Bowtie]

Gary,

Just like before, The fan hub thread is a standard, right-hand thread. The water pump is reverse rotation, just like most other late small block Chevys with poly-V belt setups (serpentine). You can used a 1-3/8" open end wrench, large adjustable (Crescent) wrench, or a 36mm and a strap wrench around the pump sheave to hold it. You would turn the wrench counter-clockwise to loosen/remove the fan. FWIW, the thread is M30 x 1.5.

[gat1954]

Thanks BlueTie.......
I used the wrenchs From Autozone..... worked ok....I had to give it a hard wrap with the Hammer to lossen.... then I turned it from Right To left....

was an easy Job after getting it off,, and putting the aniti- seaze Compound..

Take care all,,Thanks for the Great Thread..!!