What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Coolant leaking from behind the block - 1990 Blazer 5.7L

S

sw99

1/2 ton status
Joined
Jan 19, 2009
Posts
154
Reaction score
0
Location
Colorado
Got it out for a test run on the highway to break the gears in... Parked it and noticed it started to spew coolant from the back passenger side of the block area. First I thought it was a core / freeze plug but after pulling the starter it was not. Started it up and the best I can tell is it's coming from up behind the block. My thought now is possibly the intake manifold gasket?? Never delt with this before but it seems like quite a decent leak for just a gasket? I did rule out the hoses and the heater core fitting on the back of the manifold. Could it be possible to dump a lot of coolant from the manifold gasket? I just cant imagine what else this could be. Any thoughts?

My next task will be to get an inspection mirror to see if I can actually isolate the leak. Also I did check that theres no coolant in the oil or oil in the coolant.

Thanks folks!
 
I bet it is that fitting at the rear of the intake manifold. I have seen many fail and rot away.

If the hoses are original I would bet money on it.
 
bradshawtech said:
I bet it is that fitting at the rear of the intake manifold. I have seen many fail and rot away.

If the hoses are original I would bet money on it.
Click to expand...


Definitely most likely. If it's going to leak from the intake gasket those leaks usually show up right after an intake/gasket change.
 
Already checked that. I completely disconnected the hose and checked the fitting as well. I was hoping it was that but unfortunately it isn't. The Blazer has 236K but supposedly the engine was rebuilt approximately 40K ago.
 
Ive had both, the heater fitting and the intake gasket leak and both leaked ALOT.
 
If you checked the fitting and hose and were good it pretty Much narrows it down to the intake or head gasket. It's all under 16 lb of pressure so it will leak good when the engines hot. You can try and rectorque the bolts and maybe it'll be enough to stop it. Otherwise you know what ya gota do. Intakes and oil pans suck to get sealed. At least for me it has been. The lil rubber end gaskets got me a couple times and leaked oil.
 
You must log in or register to reply here.

Latest Posts

Top Bottom