Checking head flatness

[Adam]

As above.
Picked up a 14se head, looks alrate, all valves etc look fine.

Is there anyway to check the flatness of the head? Check its not warped?

I've heard about a piece of glass to check it, but i dont have a piece,Lol.

I dont want to pay ?40+ for a skim if it doesn't need it.

Also, the exhaust valves have carbon on, thats flaking off, whats the best thing to remove it? Thought about a small wire brush, but it might damage the valve head?

Cheers :)

[craig green]

good straight edge. ie steel rule held upto sunlight.

[Adam]

Ok mate, i'll see if i can find something suitable.

[General Baxter]

stop moaning, you dont have a bit of glass bollox

just blonk it on the window

[chimp007_uk]

i stripped an rebuilt a cbr400 engine, the valves on the head had 3mm of carbon baked onto them, it was white... i used a dremel and a small brass wire bush attachmant, worked a treat, no damage. just go slow and don't push hard. works well on the ports as well. just don't use a steel brush on the aluminium head!

[John]

40+ for a head skim, i think you've been going to the wrong place Lol! i always have heads skimmed before fitment, it's the only way to guarantee a true flat face, and no seating issues. I wouldn't like to trust a piece of glass!!

[Stuart]

esp as glass isnt flat ;)

[Adam]

I was quoted ?43 over the phone, why how much can you get it done for? ;)

[General Baxter]

esp as glass isnt flat ;)

correct as glass is a liquid :thumb:

[SuperNova!]

Glass is not a liquid

[General Baxter]

Glass is not a liquid

bet you 50p it is

[Stuart]

bet you ?10 it is ;)

its a supercooled liquid...

[General Baxter]

bet you ?10 it is ;)

its a supercooled liquid...

thankyou :thumb:

[SuperNova!]

How can it keep a solid state under standard conditions if it is a liquid?

[Stuart]

you didnt pay attention in physics then....

http://en.wikipedia.org/wiki/Glass

[SuperNova!]

In fact it is neither a solid or liquid realy and sits somewhat in the middle (Thinks back to the chemistry days),

It can be called a liquid, because of the type of bonding and the lack of a distinct crystal lattice structure and is seen by some to be a liquid with a very high viscosity.

Although under standard conditions it is a amorphous?iirc solid.

[SuperNova!]

No but I paid a lot of attention in Chemistry I wrote the reply before I seen your last post

[Stuart]

take old church windows for example. the bottom is fatter than the top....

[SuperNova!]

I remember my lecturer talking about this,

The reason very old pains of glass in old churches were thicker at the bottom is:

During the process of making the glass which iirc was the "crown glass process" the machinery wasnt very good and the glass ended up being thicker at the sides and when the glass was installed it was usually done by putting the glass heaviest end down, thus the glass being thicker at the bottom.

:thumb:

[John]

Who was the 43 quote off? you tried yates in longton? Try haggling too!

[SuperNova!]

I just take mine to a local precision engineering place 20 quid a time to make it flat.

:thumb:

[Adam]

An arguement about glass seems to have kicked off :plollol

I might just risk it anyway, it looks flat,Lol.
What started off as a cheap 1.4 engine is really starting to build up in cost.

[SuperNova!]

All it can cost you if the head ends up being warped is a new headgasket (tenner) and a head skim assuming you can do the work yourself,

As long as you catch the headgasket as soon as it goes if it does before it does any damage to the head you should be fine.

:thumb:

[Matt2107]

Hmm head skimming...

I remember when me and my dad did the cam shaft on a 1.2
We mulled the idea of having the head skimmed for a while.... then settled for 5mins with a bit of emery paper...

Those were the days.

[SuperNova!]

Sanding down the head??

There is no chance you could get it flat with some emery cloth :confused:

[BigStan]

My mate has a bit of metal that is super flat, its Snap On and thats what i checked my head with !

[Stuart]

ive sanded down iron heads before and they resleased perfectly ;)

[Matt2107]

It was a case of rub it down for a bit, plonk it on, bolt it up and pray.

It worked and I did another 30,000 miles on it before I scrapped it.

Wouldn't do it now though.

[dannyb]

To check flatness, you need a surface plate and engineers blue, it will leave an imprint on the plate and you can see which bits aren't touching it and whether it neds a skim.

[Adam]

You can finish the head surface off with some 1000 grade wet/dry, to get it nice and smooth.

I dont know much about the heads past, apart from it came off a corsa sri that someone broke for spares, but why did they break it.... Lol

Might take it a local engineering place tomorrow and have it skimmed.
Do the valves need be taken out tho?

[John]

Only if they're protruding out of the head. if they're recessed then you should be fine, of course this also depends on how much they skim off your head Lol!

[Adam]

I want the least amount skimmed off.

Incase it ever needs doing again in the future.

[John]

They'll have to take off as much as they need to get it 100% flat.

[Zakstaff]

mate you dont risk ruining your engine by putting a un-skimmed head on thats just daft.

[SuperNova!]

You wont need to take the valves out but when you get it back go to a normal petrol station and give it a damn good blow out with the pressurised air gun to get all the swarf out of it.