Rusty stain at rear of block/heads? - ZR-1 Net Registry Forums

VetteMed · 04-22-2010

As I mentioned in my other thread, there's some rusty stained areas around the block/head junction around cylinder #7, also around the freeze plugs in this area:

Any thoughts?

todesengel · 04-22-2010

again, I am no expert on these engines lol.

Most bhg's, in my experience, are found from combustion chamber to coolant passage. I would have a hard time buying that what is shown in your picture (intake side) is from a bhg. "most" bhg's show signs by introducing exhaust gases into the coolant system, and are readily identifiable by temp fluctuations, overheating, and over pressurization of the coolant system.

That looks like "crap" that ran down the head. I see no evidence of coolant (usually causes a stain with a white outline) on the aluminum.

If you are still wary of the possibility, pull the plug and "scope" the chamber. generally if you have a bhg the piston will be "steam cleaned" from the introduction of coolant into the combustion chamber. You can also perform a leak down test, or a napa block sniffer to put your mind at ease.

Just from my experience with other engines, I do not think you could identify that as a bhg from the pictures, and I have dealt with a ton of them on old 7m supras.

Oh, oa couple other indicator that came to mind is you will also see bulged/swollen hoses cause by the overpressurization of the coolant system, and a boiling in your overflow while idling, or after you turn your engine off.

phrogs · 04-24-2010

I would just clean it up and drive it.

Of course if there are no secondary indications of a blown gasket I wouldn't worry about it but thats me.

Its a high mile car it is obvious that it is showing the dirt and grime of being driven and a fe oil leaks could be it was wash in the past and that is from water running down that area??

Does it wipe off or is it stained? Could just be dirt and grime.

04-22-2010	#1
VetteMed Join Date: Mar 2009 Location: Orlando, FL Posts: 1,828	Rusty stain at rear of block/heads? As I mentioned in my other thread, there's some rusty stained areas around the block/head junction around cylinder #7, also around the freeze plugs in this area: Any thoughts?

04-22-2010	#2
todesengel Join Date: Apr 2010 Location: O'Fallon, Mo Posts: 738	Re: Rusty stain at rear of block/heads? again, I am no expert on these engines lol. Most bhg's, in my experience, are found from combustion chamber to coolant passage. I would have a hard time buying that what is shown in your picture (intake side) is from a bhg. "most" bhg's show signs by introducing exhaust gases into the coolant system, and are readily identifiable by temp fluctuations, overheating, and over pressurization of the coolant system. That looks like "crap" that ran down the head. I see no evidence of coolant (usually causes a stain with a white outline) on the aluminum. If you are still wary of the possibility, pull the plug and "scope" the chamber. generally if you have a bhg the piston will be "steam cleaned" from the introduction of coolant into the combustion chamber. You can also perform a leak down test, or a napa block sniffer to put your mind at ease. Just from my experience with other engines, I do not think you could identify that as a bhg from the pictures, and I have dealt with a ton of them on old 7m supras. Oh, oa couple other indicator that came to mind is you will also see bulged/swollen hoses cause by the overpressurization of the coolant system, and a boiling in your overflow while idling, or after you turn your engine off. Last edited by todesengel; 04-22-2010 at 08:20 PM.

04-24-2010	#3
phrogs Join Date: Jul 2004 Location: Kalamazoo MI Posts: 1,744	Re: Rusty stain at rear of block/heads? I would just clean it up and drive it. Of course if there are no secondary indications of a blown gasket I wouldn't worry about it but thats me. Its a high mile car it is obvious that it is showing the dirt and grime of being driven and a fe oil leaks could be it was wash in the past and that is from water running down that area?? Does it wipe off or is it stained? Could just be dirt and grime.