Porting exhaust manifolds?

Smut said:

The rust is def engraved in. But like i said i was just bored. Im cleaning the heads now, if they are cracked will i be able to see it?

Click to expand...

Depends. If the cracks are big enough, you might. Although if they are big enough to visually see by eye glance, there will most likely be some symptoms along with it. Magna-fluxing the heads tells the tale. Most tiny fractures will be facial. In the area around the guides and seats, under the valve, you will see them if they are there. Sometimes the cracks will run passed the seats and cross from valve to valve. Unfortunately, if you have a crack that runs from valve to valve, across the combustion chamber, 9 outta 10 times the heads will be junked in favor of a new core set

Smut said:

The rust is def engraved in. But like i said i was just bored. Im cleaning the heads now, if they are cracked will i be able to see it?

Click to expand...

You should be able to see it, yes. Look for cracks in between glow plug holes to intake and exhaust ports. If you can, you may check the valve seats for cracks, too.

exhaust seams to attract rust anyway, im working on an engine at work that has 3 broken exhaust manifold studs, and everything else was rusted as ***... sucked, i dont think anything keeps exhaust from rusting LOL.


ON the heads, i had a hard time seeing the crackes when i did mine, once they are pretty clean you can probably see them, but the easiest way to check for cracks is to tip the cylinder head up so the exhaust port is facing up, then put some brake cleaner in the exhaust port, if they leak around the valve you will know right away, you will have brake cleaner coming from the valves and the cracks will show up right away, check all of them too.

Mine were cracked all the way to the glow plug hole, but the machinist was comfortable with fixing them, i dont have a ton of miles to say that its a legit fix but it seams to be ok so far.

I have the heads pretty shined up so far. Doing this type of work is addicting in a sort. So pour brake cleaner in the exhaust port and if it leaks its cracked? Im using these heads for cores to send to ede for porting so does it really matter?

yes exactly a good cylinder head should not leak any fluid from it, the cracks start in the exhaust seats and work their way out.

Yes it will matter, no since in porting a junk head LOL, if the cracks arent big hardened valve seats can be installed just depending on the cracks and the machinest.

What about the intake valves? Fluid as well or...?

Yes

**on edit- I can not stress to you enough to just have the heads magnafluxed and be done. Tadd is going to before he ports them anyway. Nobody in their right mind works on heads without. Its just the smartest and easiest way to know for sure what you have to work with

What does magnafluxed mean?

Basically it works by applying a magnetic field to the component under test using a permanent magnet which causes a high concentration of magnetic flux at surface cracks, which can be made visible by dusting iron powder or a similar magnetic material over the component.

Parts can be tested using one of two methods. The wet method consist of bathing the parts in a solution containing iron oxide particles. The wetted part is then placed in a magnetic field and inspected using a ultraviolet light. The iron oxide particles are attracted to surface discontinuities or cracks, where the magnetic field is discontinuous. The particles flux around the imperfections and the patterns are visible under the black light.

The dry method is based on the same principle. Parts are dusted with iron oxide particles and charged using a yoke. The particles are attracted to the discontinuities and are visible by black light.

Click to expand...

Wow. Where do i find someone to do this?

That, Im confident you can handle without anyone holding your hand

Intakes aren't as important because the heat isn't nearly as great but it wouldn't hurt to check them. The brake fluid is a quick check. Any machine shop can magniflux then