Coolant leak left rear side of block

[oldbejuanyaknowme]

Or, if you want to try something that will not hurt anything, put in the large bottle of Q-Seal and follow the directions. My head gasket ('96 7.4L Gas) was leaking bad and thought I would need to replace it or rebuild engine. That was 26K miles ago. I put a new bottle of Q-Seal in with each coolant change (about every 12K). No leaks, no issues, truck runs perfectly.

 

[Coveman]

Word I heard was that Gm adds stop leak to new engines for a little leak insurance (https://www.google.com/aclk?sa=L&ai...hUKEwiMjue8-M3tAhUjwFkKHTzZBLMQww8IlA0&adurl=)

I’ve used several coolant stop leaks like Barr’s with good results for pin hole leaks and freeze plugs that seep.

As for the intake gaskets, use the felpro gaskets and consider replacing the fuel spider while you’re in there.

 

[96-2D-Hoe]

Word I heard was that Gm adds stop leak to new engines for a little leak insurance

Obviously best to do it correctly as shurkey posted. But GM did use coolant sealing tabs. I have a leaking intake manifold and using these stops coolant from reaching the ground on my truck. Might buy you some time. Put a couple in the rad before you go on a decent run. Seems to build up a crust at leak points over time. Made from ground nutmeg shells and silica
AC Delco 10-108

 

[Schurkey]

BIG difference between adding tab of sealer to an otherwise new engine as a preventative measure; and expecting a tab of sealer to "fix" a corroded soft plug or damaged gasket--parts that have gone beyond their service life.

 

[Hipster]

Guaranteed the other core plugs are not far behind and for the 2 in between the trans and engine, the engine needs to come out anyway.

I did pretty much what Schurkey describes to mine 12 years ago. Gaskets/rear main seal, timing set , core plugs, oil pump driveshaft collar etc. Once and done. Weekend job

Sealer or a sealing tab is not going to save a core plug that's ready for the center to crumble and fall out and the threaded rubber butt plugs aren't a good solution either.