• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

H.O. Water pump leak bad machine work

3500GMC

What T F, over
Messages
5,543
Reaction score
863
Location
Nashport, Ohio
Excuse me while I re-machine my water pump..

A nagging coolant leak led me here. Found the block to timing housing leak. This one caused a raised eyebrow or two.

Anybody run into this on their H.O. Pump?

The shiny areas is the mill bastard file doing it's thing. Took a minute or two to get it looking better by straight edge. Geeesh.
 

Attachments

  • WP_20140914_002.jpg
    WP_20140914_002.jpg
    75.9 KB · Views: 13
  • WP_20140914_004.jpg
    WP_20140914_004.jpg
    70.1 KB · Views: 13
  • WP_20140914_006.jpg
    WP_20140914_006.jpg
    75.6 KB · Views: 13
Got about 15k miles on it.. I bought it from the guy that had a 6.5 in the green '94 Camaro. He sent me the pump with the plate still bolted to it. I just slapped 'er on, lol.
 
I wonder if you are going to run out of clearance on the impeller to backing plate when things get hot? I use the silicone gasket maker on both sides of the gasket so I doubt I would have noticed.
 
I've been down this road on the old style pump before. He over tightened the pump when he mounted it to the block, but the pump to plate bolts were ok. Over torqued fasteners are a common mistake.

I'm with WarWagon on the clearance concern. I almost never use the gasket, but I would in this case,2 if needed with sealant between them. I would be liberal (hurt my fingers typing that) with the Right Stuff.
 
Impeller is .032" in the hole, gasket is .030". Should be good. The first go around I used Ultra Black RTV for the timing housing to block. Not the thing for me I'm now finding out. Had a front gasket and seal kit in stock so it was an easy decision this time. I like to use a conservative amount of RTV just on the inner edge if I'm using gaskets for coolant, usually dry for oil.

We'll see what this brings.

I did take note that somehow 2 IP gaskets were stacked and guess what that did.. LEAK. The 'ol Driptroit. I may or may not have done that. ;)
 
Happy to report, no more coolant leakage.

Side note, timed the IP a little more conservatively on advance. Still advanced a nickel width. This makes the truck slightly less responsive on the bottom but really gets some heat in the turbo (more boost per w/g setting) on the large end. With 4.10's that's a good thing.
 
Back
Top