1990 MITSUBISHI MONTERO

[Rendragyarrum88]

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[MonteroVictim13]

I could use your advice.

I have a ‘90 Montero 4x4 that blew a head gasket in early January (a month after buying it), diagnosed by shop due to overheating, stalling, and coolant pouring out the bottom of the engine bay when running.

We performed a leak down test on each cylinder of both banks.
• Cylinder 1 - tested at about 50% and blew air into the coolant reservoir.
• Cylinder 3 - worse at 33%. 54 psi given, it held at 18 psi and started bubbling the coolant reservoir again.
• Cylinder 5 - While turning the engine over by hand to test cylinder 5, a good amount of coolant puked from somewhere on or near the head. Cylinder 5 was also bubbling into the coolant reservoir, but it held 25 out of 35 psi.

All 3 cylinders failed on the passenger side, but the drivers side cylinders all passed. All of this pointed towards a damaged head at the very least. We believed the puking coolant came out of cylinder 3 spark plug hole. Which can cause hydrolock or a bent piston rod. We checked for warpage and found about .007-.008 (7 to 8 thou) in the worst spot of the passenger head cylinder. Maximum allowable is .002.

So we went with addressing the cylinder and gasket. The passenger head cylinder resurfaced by a mill, cleaned, and reinstalled with every new seal known to man (except the rear main).

Now there’s a steady stream of oil pouring straight down from the passenger side (potentially the forward most exhaust manifold stud), video of the leak is attached. The expert I’m working with didn’t take steps to identify where the leak was from while the head was off because “there’s no good way of checking a nonferrous head other than visual inspection. Since they’re not magnetic, you can’t check with Magnaflux.” So his plan is to remove the ex man stud, coat it in loctite or teflon tape and reinstall. I’m afraid the block or head is cracked…

What would you do in this situation?