How To: Revive Old Copper Head Gaskets

[IT400C]

Quick question for you guys....

I'm rebuilding the motor on my IT400C, and it's been sooooo long since I've worked on an air-cooled motor that I can't remember if there is an "UP" side on the old copper head gaskets...

I have a vague memory that there is a specific way up, but for the life of me I can't remember what it was.  I think it should be raised side up/flat side down....

Does anyone know for sure?  

Also, I remember that you used to put your used copper head gaskets in the oven for a period before you re-used them (something to do with re-conditioning the copper so it would seal properly again)

Anybody (mboddy?) remember what the time/temp is?  

Thanks guys,

Tony

[Evan]

my IT200L has "up" written on the gasket. i have not used this "oven" method but i would think it would work because when the head is bolted on it compresses the gasket and when the head comes off the gasket stays compressed not filling the gaps when re used. my KD80 had this - old head gasket = 5 PSI compression new head gasket = 110 PSI compression. better off to spend $25 or $30 to get a new head gasket.

[IT400C]

Yeah, I've always used new head gaskets wherever possible, but they're getting harder to find these days for the 1976 IT..  I've got 4 new ones at home that I picked up reasonably cheaply a little while ago, but they're going for around US $50 these days... 

4 new head gaskets between 2 IT400C's should see me through to the end of their useful life.  The bike I'm rebuilding at the moment will be more for show than for riding, so once it's rebuilt, it'll rarely be used - it's next piston will probably still be as new in 20 years time!!   

[F.Gassit]

I don't know about the oven. My old man used to put the head gasket on the gas stove burner. You heat it up to a very dull cherry red, then let cool ( no quenching ), this is called "anealing ". Makes the copper soft again. I think he was able to re-use the same gasket two or three times...............

[IT400C]

yeah, that's sounding vaguely familiar - I knew there was something they used to do...

 I remember annealing now from back in my old high school metalwork classes...  we did some copper beating, and if you had to re-work the copper, we had to heat it so it didn't split...

Obviously it's still better to use new head gaskets where you can, but sometimes you just can't....   

[Bigbird]

Kato is near spot on, anealing is heating up on a gas burner until it glows red then drop it in cold water or you can let it cool down naturally it doesnt matter which way.

[Guilly]

The best option is a new gasket, when i was young and broke i tried the anealing procedure several times and it never worked successfully the head always leaked, infact I managed to strip a stud on the 360A by tightening too much to try to get it to seal. Get a new one if you can, Do u think that heat proof red silicone would have a chance of sealing a used gasket? It works magic on the exhaust manifold and that must be a fair test for anything. My 250j has run 3-4000k and the exhaust is still dry as dead dingos donga!
Guilly
PS If you find a place to get new head gaskets I'll have one for the 250J pleare.

[Bigbird]

A freshly anealed copper head gasket is as good as a brand new one,buying a new one is a waist of money....BB

[IT400C]

A freshly anealed copper head gasket is as good as a brand new one,buying a new one is a waist of money....BB

well, I have to admit, I'll always use a new gasket if I can.  But for something like my 400C which only does amybe 4 laps of a Vinduro course every year, it just seems like a waste of a US$50 head gasket that is getting harder to find every year...

I haven't annealed one for re-use yet, but I probably will at some stage.

And I know it was used a fair bit back in the day.

[Helmet_Hair]

I'd like to see a good write up on a successful job here.  Somehow I doubt the flame from a torch would heat the thing evenly, and one may have to use a gas stove burner to heat the entire gasket at once...would that sound about right?

[ws6transam]

I remember having a head gasket leak and I took my IT250K into the Suzuki shop to get a new head gasket. Rod Smith looked at my bike, and said "hey, wheel it on back to the shop and we'll try something first." So we wheeled it back there, and he popped off the head, pulled the gasket, heated it with a propane torch, then dropped it into a bucket of water. He fished the gasket out, popped it back onto the motor, buttoned it up, and didn't charge me anything. That cylinder head gasket never leaked again.

[Martin I Henry]

   I anealed my YZ125E head gasket and made a simple former to put the raised ring back into the surface.
  It's just like a new one now !

  Planning to do the same to my IT425G gasket.

   Dave R

[F.Gassit]

I was thinking of a former,..........what'd you use Dave??

[Griffo]

If annealing the gasket doesn't work for you, try some VHT Copper Spray. Comes in a Pressure pack.
Otherwise, you could always slip a ring of soft copper wire under the head gasket in the trough, on the opposite side to the main sealing ridge. That will make it seal.

[Martin I Henry]

I was thinking of a former,..........what'd you use Dave??

  I used a large pipe fitting, thinned and rounded the end on a lathe. I then placed the gasket onto a sheet of conveyer belt rubber that was about 12mm thick, positioned the fitting carefully and tapped it lightly with a raw hide hammer.
  Either by luck or judgement it was correct the first time !!!

  Remember I was only working on a YZ125 gasket, a big bore item may need a different approach.
  For the IT425 I may make something up to use on the workshop press, not for the power but the accuracy and ease of positioning.

   Dave R

[F.Gassit]

perfect!!........    Thanks' Dave ...........press sounds like the go....

[rodeobob]

Heat it, quench it, and then spray it with chromebrite. 

slap it together.




Bob.

[Guilly]

Bob I seem to remember back in yr7 at HS quenching in oil is this the preferred option or am I dreaming. Anyone else?
And Im thinking if I try this maybe the open fire might be a good place to get the gasket uniformly hot. How do you do it? As I said earlier I have not had much luck with used coppers in the past but the consensus is in favour so I might give it a go. As yet I have not had the head off and curiosity is eating away at me. And I do like to pull things apart.
Guilly

[rodeobob]

Theres no need to pull something apart just because you can.



Bob.

[golly]

heat the old copper gasket on the stove then let to cool down after about ten min  put it back on the bike and it sealed good no leaks lots and of comp.

golly

[dar373]

qquench or not???oil or water??

[golly]

just let it cool down slowly enough so you can hang onto it in your hand, then put it back together.

golly.

[jason70]

Kato is near spot on, anealing is heating up on a gas burner until it glows red then drop it in cold water or you can let it cool down naturally it doesnt matter which way.

yep BB has got the way and i have always done it the same way and never had a prob cheers

jase

[Roosty]

Theres no need to pull something apart just because you can.



Bob.

there's a sence of adventure though.... 

[1983]

I am a plumber and work with copper allday. heat gasket with gas torch a nice even red let it cool. no need to quence non-ferrous metals, it is quite thin and you will be able to handle it after about a minute. Ferrous metals are quenced with water or oil for hardening. 

[Martin I Henry]

   The advantage of quenching is that the oxides that form during the heating process plus any carbon left on the gasket fall off due to the rapid drop in temp.

   Dave R

[killindini1]

Groove up or down??

[Martin I Henry]

Groove up or down

Groove up Monday to Friday. Sat and Sun I try and groove down !!

Dave R

[1983IT490K]

I didn't realise that you did it both ways Dave!  I thought you were just an average bloke!