water pump bolts

[Stewart G Griffin]

Do you know what size/length and thread the water pump bolts are.  And, do i need to put any sealant on any of them?

[zieg85]

I always use never seize on anything that goes in a water jacket.  I know they are 3/8" 18 thread, but exact length escapes me.

[rich weyand]

Jegs says 3/8"-16 x 2"
http://www.jegs.com/i/JEGS-Performance-Products/555/83901/10002/-1?parentProductId=2088417

[Stewart G Griffin]

i guess what i was trying to ask was, do any of the bolts go into a water jacket?   Especially, the top driver's side?

[bd]

i guess what i was trying to ask was, do any of the bolts go into a water jacket?   Especially, the top driver's side?

All four W/P bolts penetrate the water jacket on a small block.  Use non-hardening Permatex #2 or Teflon paste sealer on the bolt threads.

[Stewart G Griffin]

Oh great.   Oh well, this engine is getting ready to come out anyways.

[bd]

They're not difficult to reseal in the interim - just wire wheel the threads one at a time and reinstall them with some sealer.  It helps to chase the threads in the block, but isn't absolutely necessary.  The slightly more involved repair would be if the W/P gaskets were deteriorated to the point of needing replacement.

[Stewart G Griffin]

The other thing i wanted to ask was what thread size is the water pump pulley flange?   It seems like they are machined just a little "off" so that the studs don't vibrate loose?

[bd]

The flange should be threaded 5/16"-24.  Typically, four ~1" studs are used that are 5/16"-24 (NF) on one end and 5/16"-18 (NC) on the other.  Grade 5 nuts with split washers retain the fan or clutch to the W/P flange.