I've got the LT4 ED Timing Set. How do I remove the upper water pump gear? The PN is 12551728.

I need to put the water pump gear on the water pump driveshaft. I removed the 2 torx bolts that hold the locking plate in but it won't slide out easily... at all. It seems I will need to install the gear onto the Water Pump Driveshaft.

Sorry for the picture size, it is a link from a website.

 

With the two locking plate bolts removed, it's likely the whole drive assembly will pull out before the gear will come off. Maybe one of your gear pullers will work on the gear?

 

I pulled off the two locking bolts. It won't slide out. The diameter of the Water Pump Gear is smaller than the Water Pump Seal so it won't slide off it I pull the gear forward. It seems the whole driveshaft has to come out, then put the gear on from the backside.

I'm wondering if it is press fit but I'm concerned about tapping on a bearing.

For everyone who got the LT4 ED, they must have replaced this gear along with the cam & crank gears right? It comes with the kit.

 

I checked the back side with a mirror and it is a large bearing that is press fit into the hole.

Did most of you who replaced your timing kit with an LT4 just leave the water pump gear alone yet replaced the other parts in the kit?

Since it is a bearing, I have reservations about tapping it out and aligning it up.

 

The bearing is attatched to the WP drive assembly. If removed, you can simply tap the complete assembly back into the block.

 

With the intake and the two plate bolts removed tap on the center of water pump shaft with punch and hammer from the intake side, once the assembly is out of the block you will need to press out the bearing and the gear from the back side of the gear assembly. pay close attention where the gear is positioned on the shaft before and after. also make sure your bearing is good and the shaft isn't grooved. the differance of the gears is the hardness. some people don't change them and don't have problems and others do.

 

Ok, so I'll tap the water pump drive shaft out from the back side. Will the bearing stay in the block?

 

No, the bearing is part of the drive assembly.

 

no the bearing will come out with the shaft.

 

Thanks. Just to wrap this up, the bearing in fact did come out with the water pump drive shaft. I used the 2-jaw puller to slide the gear, the retainer bracket, and the bearing off the back side. It was like a steel shishkabob.

Fortunately, I had a small vise to secure the puller which let me concentrate on slowly pulling the items.

To put it back together, I used the 2-jaw puller for the gear to slide it on towards the front. Followed by the retaining bracket. Then I put the bearing on the anvil of the vise and tapped the shaft down into the bearing until it bottomed out. I used a 1/2" deep socket to slide the bearing down onto the shaft until it bottomed out on the ledge of the shaft. Then tapped the assembly back into the block using the 1/2" deep socket to protect the threads.

Phew! It wasn't that bad but I wasn't ready for that.

Thanks for your help everyone!