Head Cleaning Question?

[robw13]

Hi,

If I take the Heads off my 74 SE, will they need to be taken to a shop before puttin then back on? The heads aren't blown just want to clean em and put new valves in.

 

[Garys1969RR]

I always have my cyl heads cleaned and inspected for burnt valves, loose guides, seals, etc. Then re install using new head gaskets. Is there a prob with the heads now? What size engine are you workin on? 400, 440?

 

[robw13]

5.9 360, believe the valves/seals are burned up due to lots of oil smoke. The heads themselves I think are ok. Didnt know if I could do a valve job without taking the heads to a shop?

 

[coloradodave]

Rob,
You can't do a valve job without the proper machinery. It's not just removing and replacing parts. The reason to take the heads to a reputable shop is to assess the condition of all the parts. Normally, the existing valves can be refaced (mating surface under the valve head ground smooth and valve stem tips flattened). The shop will also check the flatness of the head surface (surfacing it if necessary) , the condition of the valve spring retainers and locks and the tension of the springs. They then will grind the valve seats in the heads and mate each valve with its seat. Of course new valve stem seals will be used upon re-assembly. Most shops have a flat rate to disassemble and assess the condition and to be able to give you a total cost to re-do the heads. Cleaning is normally done in a hot tank or chemical /vapor degreasing machine.

 

[WileE]

Yes, in addition to the good advice by Dave, the guides must be checked for excess wear, if knurling or new guides are needed. Also, to check for any cracks in the seat area. As long as they're out, put them back in the right way.

 

[robw13]

K thanks guys, just wanted to make sure.

 

[rev.ronnie]

Before you leave them at a shop anywhere, ask what kind of valve seat runout gauge they have, and what kind of valve guide bore gauge they use. If they have neither, go elsewhere.

Ask also, what their valve face to stem maximum runout and seat runout tolerance is. If they can't tell you it's less than .001", again...run away.

 

[robw13]

Gotcha, thanks

 

[robw13]

Another question, what's the best/easiest/fastest way to clean Head Gasket Areas? Seen a lot of different ways elsewhere but wanted some opinions from here.

 

[67 coronet]

Another question, what's the best/easiest/fastest way to clean Head Gasket Areas? Seen a lot of different ways elsewhere but wanted some opinions from here.

if you are not doing any work on the short block do this:
scrape off any big stuff with gasket scraper.be careful not to catch any edges with the scraper.
then wrap bar stock or a real good hand body sanding tool with 800 grit sand paper.sand in an x pattern,not strait up and down or side to side.will not only take off any small stuff,but will check block for any warping as well.make sure you tape off the valley before you sand and vacuum out the cylinders with a strong shop vac when done.

 

[robw13]

Does the gasket scraper need to be plastic or one with a razor blade on the end?
Is the Hand Body Sand Tool like you use for paint removal?
Also, which tape is best to use?

 

[robw13]

If the heads are warped at all, I need to sand them right?

 

[mopar 3 B]

Fine wire brush for an electric drill and parts cleaner. Just make sure you have everything sealed well, shop vac the residue and wipe clean with a lint free towel. Brass brush if you can find one. You want to leave the surface smooth and there is no need to remove any metal leave that to a reliable machine shop.

 

[nm9stheham]

I just use a single edged razor blade and carefully scrape everythig clean; sanding can produce fine grit that will get into the cylinders.

Either way, once you are done, use ATF and fresh paper towels and wipe and wipe the cylinders over and over to clean; you will have to turn the crank to bottom the pistons and do each cylinder 3-4 times; the pistons moving up and down will tend to push any crap to the top of the cylinder bores where you can wipe it off. once you get a good clean wipe, you are good. Then use alcohol to wipe the head surfaces squeaky clean before you install the heads and gaskets.

Head warpage needs to be checked by a shop and the heads need to be surfaced with a special grinder if any warpage is found; you can't do it without the right grinder. Google 'cylinder head grinder'.

 

[robw13]

K thanks. Should I only Turn the motor over by Hand or can I use a trigger?

 

[nm9stheham]

I would do it by hand; it'll be easy with no heads on to build compression.

 

[robw13]

K thank again

- - - Updated - - -

After wiping the ATF thru the cylinders, do I need to make sure the cylinders are dry before putting the Heads on?

 

[rev.ronnie]

Razor blade and a shop vac to keep debris out of the motor.

 

[nm9stheham]

No, you should leave a skim coat of ATF on the cylinder walls. Or wipe them down with a thin coat of clean motor oil. A small amount (well less than a teaspoon) of ATF or oil left in a cylinder will do no harm.

 

[HT413]

Razor blade and a shop vac to keep debris out of the motor.

This is what I did. Bores were clean.