Has anyone replaced the water pump intermediate drive unit. It drives the water pump off of the cam gear. I understand that it rides on a ball bearing cage in its block locating hole. A reference book I have on rebuilding LT1s suggests that is a normal wear item and should be replaced. However, I haven't noticed any posts regarding this part and its useful life.

I have my wp and opti off presently and was wondering if I should replace this part. The reasson I am into theis part of the engine is that I am tracking down a skreeching, rotating noise that folows engine rpms at or near the front of the engine. I've replaced the pulley adjuster and the accessories appear o.k. I thought it might be the opti as I have had an opti bearing fail before. Nope, the WP and the opti appear to be good upon removal and inspection. I am running out of items to check.

Any advise regarding the wp intermediate drive unit? I'm thinking of pulling the cover off to get at it, but thought I ask for some advice first.

 

Since you are there, replace the pump drive shaft assy GM number 10219554. Pre lube it before installing it. Don't forget the shaft O-rings and replace all the seals in the timing cover. I used the connector for the pump drive to help seat the seal on the water pump drive shaft. May need to tuck it in by hand while you do it.

It's funny the shaft assy with the bearing and all is about $50.00 and the stupid little connector for the 2 shafts is $46.00.

Do you think the screeching sound you heard could have been one of the accessories on the front of the engine? A/C compressors have been my down fall before. I hate those BAS%$#@s. Are you gona replace the chain kit too. I used the HD GM chain kit.
If you put it together and it still does it, try removing the accessories and see if it goes away, (if you haven't already done it).

Good luck to you.

 

Badass383, thanks for your reply. The part #s, prices info and other ideas were helpful.

The noise I am hearing sounds to me like a bad bearing in something, hence my immediate belief that it was the belt tensioner pulley, which it was not. For months, I have placed a stethoscope on or around the engine and all the accessories. The noise appears to be coming from the front of the block, but not traceable to one specific component.

Since the sound was very similar to my original opti bearing that was failing (weeky-weeky), that was next on my list. After pulling it out, it does not appear to be the culprit. Just in case, I do plan to install the new DynaSpark replacement opti that I just acquired. I have spun the WP shaft and it seems fine too. No leak from the weep hole either. There is less than 10k miles on my WP. I have a Cloyes timing chain and gear with less than 30k miles. I hope that is not in need of replacement.

A professional engine build friend has listen to the noise and is not certain of the culprit either. At one point, I thought it was a roller rocker going bad. He and I have replaced the springs (as a separate project) and adjusted them properly. Nothing was identified there to indicate a problem. Actually we are beginning to think I may have a problem with a lifter and may pull the intake manifold to check those after the opti and that pump drive shaft assy is replaced. After listening carefully, my bud does not believe there is any bottom end problem.

This noise is really elusive!?

Geez, at this point with everything dismantled, I may just go for a cam change! Maybe time for something stouter.

 

Naw, the engine in the picture was from a police engine I bought to build up while I drove the car. Those lifters were fine and are back in the engine and doing fine . Your squeek is not lifters. Even if they did squeek you wouldn't be able to hear them. If you don't find it, let it go. You did everything you could to find it and it can't be that bad.