Red neck head check

A machine shop can do this type of testing but they don't use rags. They plug all the holes, pressurize with air and submerse the head in water and look for bubbles. Steve

Clean the head with cheap lacquer thinner (or equiv) and cover the head gasket surface and water ports with duct tape.

Stand on end and fill slowly with water.

Besides the pressure check already mentioned, some shops do a less expensive test with vacuum.

There is also a pink liquid penetrant, looks just like Pepto-Bismol, that will seal those cracks. You fill the head, leave standing over night, drain and air dry for 24 hours or bake. Kind of pricy if you are only doing one head, but economical when recover and reused.

WOuld it be better to do the duct tape or to add pressure and stick it in a tank.

Thanks guys for the duct tape idea!

I wish I could find one. It is 60 bucks around here.

WOuld it be better to do the duct tape or to add pressure and stick it in a tank.

Thanks guys for the duct tape idea!

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Hard to say, it depends on your particular leak, so I guess you could say pressure is better, but just seldom actually necessary. I think most (but not all) cracks will leak standing water if they leak at all. But again not always.

But the duct tape and standing water is just something easy to do at home. You have to have some pretty substantial block off plates to add pressure, and a large enough dip tank if you care where the leak is coming from. Keep in mind, most shops don't care where a leak is, to them any leak scraps the head no mater where it is located.

I wish I could find one. It is 60 bucks around here.

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Have you called more than one shop? It can be well worth the drive.

Seal the openings, dry the head thoroughly and fill with kerosene. This is the best way to find cracks with a liquid.

Melt some wax appx. size of the round openings, freeze the wax and screw the wax plugs into the openings quickly.

j/b

You can clean the head real well and then spray on a coat of thinned oil - diesel will work. Wait a bit and then wipe all the oil off and then sprinkle powdered chalk all over the head. If there is a crack the oil will leach out of the crack and the chalk powder will adhere to the outline of the crack and darken.

Or you can but a "dye check kit" and do it the modern way.

Cheers,

Bruce (bruceinbangkokatgmaildotcom)

The surface tension of water makes it less likely to leak through a small crack. Kerosene will often do better or a little soap in the water might work.

I have taped up the ports and pressurized with the outlet of a vacuum cleaner or an air blow gun to find some leaks. Just a little air pressure and some kid's bubble solution seems to work pretty good for me sometimes.

It is very controversial but Bars Leaks or other sealers sometime work well.

Don Young

That still won't tell him if the crack leaks water.

True, but then again if there is a crack and it doesn't leak HE probably doesn't care about it..... Cheers,

Bruce (bruceinbangkokatgmaildotcom)

I got to thinking, I know this is a "red neck" way of doing this but

Would it be better to plug the ports, pressurize with air compresser, then dip in a tank of water and watch for bubbles? Or To plug the ports, pressurize and spray saop and water on the head?

When you talked about using a bubble solution I was not sure if you meant inside of the head or on the head.

Called several. I guess nothing in life is free.

Called several. I guess nothing in life is free.

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You couldn't find anyone to vacuum check it for less than $60?

No one around here even does vaccum check. Almost 100% do only magnaflux. Only 2 shops pressure check. ( I live in a relatively small area.)

No one around here even does vaccum check. Almost 100% do only magnaflux. Only 2 shops pressure check. ( I live in a relatively small area.)

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Bummer, did you try the duct tape and water?

Would it be better to plug the ports, pressurize with air compresser, then dip in a tank of water and watch for bubbles? Or To plug the ports, pressurize and spray saop and water on the head?

When you talked about using a bubble solution I was not sure if you meant inside of the head or on the head. To me, the easiest way is to turn the head upside down so that the bubble solution will pool around the suspected crack area in the combustion chamber. You only need a thin layer. Then stick the vacuum hose or blowgun into a coolant port and blow as much pressure into it as you can reasonably manage, just holding the hose with a rag around it or something similar. It doesn't take much pressure to make bubbles.

This is not a 100% sure method because there are cracks that leak only under high pressure or temperature but I have found it to be very useful and it's cheap enough.

Don Young

Back in the 70s, we used to check for cracks in Harley heads by degreasing the part as well as we could, then leaving them in a warm place (dashboard in the sun usually worked) for a day or so. Removed the part, then dusted them with talc (chalk, as mentioned earlier, would also work, I suppose).

Any oil that seeped into a crack would remain behind after the degreasing, and would exude out enough to show up using this method. We called it "the poor man's magnafluxing".

Of course, if the crack in question was in a water jacket area (no oil), you probably would just have to air dry the head for a couple of hours, and then dust it. I don't know how well it would work in that case, though.

Just random thoughts escaping...

Joe

Is your time free?

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It takes less than 5 minutes to vacuum check a head. Do you think $720 an hour is reasonable?