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DaleRidesAll

Head soft spot?

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I had a bit of damage of the mating surface of my head so i took it to a head specialist and he just said that general area has gone soft? what does this mean exactly and is it fixable?

this is the head, damage is circled

10846712_10204376419989242_1285627488_n.jpg

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I had a bit of damage of the mating surface of my head so i took it to a head specialist and he just said that general area has gone soft? what does this mean exactly and is it fixable?

this is the head, damage is circled

attachicon.gif10846712_10204376419989242_1285627488_n.jpg

I think that would be best asked to the head specialist that looked at you. Also not be be a ass but this is a motorcycle site so its really not the proper place to put it.

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I thought one of the rules of this site was no shit stiring, pretty obvious the picture is of a motorcycle head.

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I rebuilt cylinder heads for years. Never heard the term for aluminum going soft. It looks like you blew the head gasket and it's worn into the head surface. Not knowing how deep it it it's hard to say but I'd think you could machine it true again. You may need to run a thicker head gasket to make up for the material that gets milled off so your tolerances and compression aren't affected. You'll also want to check the deck to make sure there are no imperfections there either.

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Wait, your mating head has gone soft?lol.

Seriously, I can't help you with the bike but am curious as I have not seen such a thing.

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I am sure the head could be ground flat. It looks like a very minimal amount of damage. It is only near a cooling passage and not near the combustion area.

I'd also have the top of the barrel ground flat too. Then to be sure safe, I'd use copper coat on the head gasket

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the damage effect almost loks like its been hit with somthing and pushes down, at the lowest point it is about .30 mm below. they said they can easily weld it up and re surface the same height that it is now but that the area around the damages has gone soft from overheating too much. i bought this bike how it is unknowingly of the problem and the guy just put fuel and oil in and rode ( only road riding as its a supermoto (wr400 is that means anything)) but is there any way to fix the soft spot?

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thats still $900 aud by the time its done, want to see if there is a cheaper option first

Find someone really good to fix your existing head or they will tell you it's junk.

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Yeah im wondering if an area has gone soft can it be re hardened or fixed or is it a new head?

 

 I'm not even so sure it's that soft. If it received so much heat your upper end cam stuff should be fried. I'm thinking a really good welder - machinist local or Millennium Technologies. Give em a call.

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the cams and chain and everything on the top part of the head is all good, so should i maybe go to another head place andget them to test it properly, the place i took it to has a sort of home made thing, still looked affective though.

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I dont know of any in my area, will do a bit of research. but even if it has gone soft is there a way to fix it?

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Look, it's not even in the fire ring.  Lap it flat on a surface plate and fill the area with a little bit of RTV or copper coat when you are putting it back together.  

 

BTW, I'm going with 'no way it has actually softenend'

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the head is a cast aluminum alloy- it is not "heat treated" therefore cannot become "softer" than it's original chemistry/physical properties. If you are in fact saying that it is .30 mm lower than the rest of the face, .0118" can be milled off the head. End result? Increase in compression. Run a stock piston and not a high compression piston and you will be fine. I second the comment about being outside the fire ring, copper coat the new head gasket and call it good.

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guys this is sounding good, im bubbling with joy at the moment in hope of a cheeper fix, so if i took it to a good head place and got it fixed and then re surfaced. a new set of gaskets and some copper coat and it should be good to ride again? anything else i should find out or is it just that

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and it go soft with severe overheating? although all the cams and stuff look fine in it no burn r scorching anywhere

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