Freeze plug locations on my 5.7 H/O 350

[azmusclecar]

I am asking this in this section hoping to find exact information on where exactly ALL the freeze plug locations are on my
1979 H/O 350.

I have a coolant leak and I am trying to discern what is causing it and WHERE. I'm almost certain it is a freeze plug but I
don't want to jump to that conclusion just yet.

The info I get on a Google search always takes me to the Chevy 350 block but I want to know for certain for OUR OLDS engines.

I just bought the car last week and today, I find the coolant leak.......and I just had to walk away from the car.......because I can see
my budget just flying out the window today. Not a good start............the leaks seem to be at the rear of the engine but I did not
have the tools or heart to crawl under and call it certain.

That will come next week when I can have the car on a lift.......but for now, I'm just looking for a preliminary diagnosis. THX AZ

 

[olds307 and 403]

There are freeze plugs on the heads and block. The block are right across the middle on the outside. The heads have one on each end, in front and behind the exhaust manifold's. Look at the corners of the intake and the valve by the heater hose with a vacuum line attached on the passenger rear of the intake. That valve leaks quite often. Good luck.

 

[azmusclecar]

There are freeze plugs on the heads and block. The block are right across the middle on the outside. The heads have one on each end, in front and behind the exhaust manifold's. Look at the corners of the intake and the valve by the heater hose with a vacuum line attached on the passenger rear of the intake. That valve leaks quite often. Good luck.

Thanks for the info, at least now I have an idea of where to start. I know of the 6 freeze plugs that run along the block. The leak seems to be from BOTH sides
of the block in the rear towards the firewall.. Water has an odd way of flowing so I wanted to start where the problem could be, rather than looking all over a wet block. When I looked up buying a new set of freeze plugs I saw the 6 plugs that go along the side of the block but I wasn't sure where the largest plug is.
Very odd for an AZ based car here in the desert ALL it's life to have a freeze plug issue but nothings impossible so I'm not ruling anything out.

Bless you for your help........I'll keep my findings posted as things progress.

 

[olds307 and 403]

It may be possible they just ran straight water which would cause corrosion. A cooling pressure tester is your friend in this case. Is it the stock cast iron intake still there?

 

[fleming442]

I'd verify the intake seal before chasing freeze plugs. As said: pressure test first!

 

[azmusclecar]

It may be possible they just ran straight water which would cause corrosion. A cooling pressure tester is your friend in this case. Is it the stock cast iron intake still there?

It may be possible they just ran straight water which would cause corrosion. A cooling pressure tester is your friend in this case. Is it the stock cast iron intake still there?

Yes car is bone stock..........

 

[azmusclecar]

I'd verify the intake seal before chasing freeze plugs. As said: pressure test first!

Good call......I seem to always run to worse case scenario, bad habit.........I'm working on that........