340 coolant in #2

[Aaaaa]

Hello I have a 340 that’s been sitting in the car for a few years without running. Freshly built with not many miles on it. Ran perfect when parked but I’m now going thru it and noticed coolant in the #2 cylinder. Any ideas? Maybe head gasket was weeping over the years?

 

[MerlinsMopars]

Intake gasket,, head gasket, possible outer header bolt weeping into exhaust port. Do a leak down test if you can.
Regards!!

 

[Aaaaa]

Thanks was thinking the same. I put fresh oil it in and sucked coolant out. Also put marvel myster oil down each cylinder, rotated freely by hand. Wonder if I should prime oil pump and fire her up to see if she’s leaking steadily?

 

[MerlinsMopars]

Thanks was thinking the same. I put fresh oil it in and sucked coolant out. Also put marvel myster oil down each cylinder, rotated freely by hand. Wonder if I should prime oil pump and fire her up to see if she’s leaking steadily?

Definitely should not be in there tho. I would consider doing a few tests to locate the culprit and make the repair. Running it with the leak over a period of time could cause you major issues down the road. Gaskets aren't that expensive.
I figure, if it has leaked in there, it's not going to stop on it's own. Hope you can find it.

 

[moparleo]

If it was running good when parked, first mark distributor location before pulling it to prime oil pump.
Rotate engine by hand while priming the pump to circulate the oil.
With a squeeze bottle and appropriate sizes small hose attached, fill the carbs fuel bowls and use accelerator pump to prime engine with fuel.
Make sure battery is fully charged.
Should fire almost instantly.

 

[Aaaaa]

Doing a leak down test when I get home if all the cylinders, will keep y’all posted

 

[413]

A leak down test is testing ring seal, no coolant in the rings. It won’t help identify a coolant leak.

 

[MerlinsMopars]

A leak down test is done thru the radiator cap, pressurizing the coolant system and will show if there is a leak in the system. Aka, head gasket, intake gasket etc.
A compression test is for rings, valve seats.

 

[gs73rallye]

As a retired mechanic, a leak down test, is pressurizing the cylinder through the spark plug hole, to check rings, valves, or head gasket. A radiator pressure test, checks coolant leaks.

 

[Aaaaa]

Ok leak down shows all cylinders at 2% cylinder 2 is way higher at 20ish %. Thinking the coolant washed the oil off the rings when it was sitting. Didn’t see any bubbles or anything in the radiator. May pressure check the coolant system to see if I can see anything before removing the heads

 

[Aaaaa]

Still no smoking gun, pressurized coolant system and it held. Any ideas?

 

[Challenger RTA]

Was the piston at the bottom?

 

[Challenger RTA]

Hello I have a 340 that’s been sitting in the car for a few years without running. Freshly built with not many miles on it. Ran perfect when parked but I’m now going thru it and noticed coolant in the #2 cylinder. Any ideas? Maybe head gasket was weeping over the years?

Freshly built.That means many thing to many people. New gasket and nuts and bolts. Or were all the components machined, checked and assemble correctly?

 

[413]

Sometimes coolant leaks change with heat and pressure on the cooling system. I’d think about removing the intake manifold and look over the gasket really well to make sure it wasn’t leaking at the front coolant crossovermpassqge.

could be a cracked head or cylinder wall, worst case scenario.

Leak down and compression tests should be done on an engine that just ran so there so some heat on it and the oil is up on the cylinders.

 

[Aaaaa]

Freshly built.That means many thing to many people. New gasket and nuts and bolts. Or were all the components machined, checked and assemble correctly?

All components redone, and upgraded. Stroked to 416, roller cam

 

[Challenger RTA]

Sometimes coolant leaks change with heat and pressure on the cooling system. I’d think about removing the intake manifold and look over the gasket really well to make sure it wasn’t leaking at the front coolant crossovermpassqge.

could be a cracked head or cylinder wall, worst case scenario.

Leak down and compression tests should be done on an engine that just ran so there so some heat on it and the oil is up on the cylinders.

could be a cracked head or cylinder wall, worst case scenario. I Didn't want to say that.

 

[Aaaaa]

Sometimes coolant leaks change with heat and pressure on the cooling system. I’d think about removing the intake manifold and look over the gasket really well to make sure it wasn’t leaking at the front coolant crossovermpassqge.

could be a cracked head or cylinder wall, worst case scenario.

Leak down and compression tests should be done on an engine that just ran so there so some heat on it and the oil is up on the cylinders.

Yeah I agree, just wanted to get an idea before I started tearing down. I’ll pop the intake and take a look, but wouldn’t that put coolant down in the oil and not cylinder if it was leaking?

 

[Challenger RTA]

When the car is running.is there antifreeze in the exhaust? white smoke that doesn't clear up?

 

[Aaaaa]

When the car is running.is there antifreeze in the exhaust? white smoke that doesn't clear up?

Car has been sitting inside for 5 years, haven’t cranked it yet, was getting it ready to crank and noticed this coolant issue so I am just trying to trouble shoot it some. Tempted to fire it up and let it warm up and then let it cool to see if the coolant is still leaking. Or if it just slowly leaked over the past 5 years. Ran great the last time it was running. It’s a TA block in my AAR so trying to be careful with it

 

[Challenger RTA]

How much coolant is it down?