Porous head?

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kokkolanpoika
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Porous head?

Post by kokkolanpoika » Wed Dec 26, 2018 8:12 pm

Hi.

What an how do you recon to repair porous head gasket face for cylinder head?

Welding is not our 1st choice because it will need at least valve seat machining etc.

Image

1. Some chemical metal. Like jb weld?
2. Custom head gasket to get wider fire ring. Current is only 3mm wide. And couple of casting fault will just go below fire ring.
3. Machine more metal for face and hope for best and porting to get correct CR?

Any good ideas?


Timo

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stevieturbo
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Re: Porous head?

Post by stevieturbo » Wed Dec 26, 2018 8:23 pm

That does need welded

I think laser welding could be done on that without the need for valve seat work.

This is a German place, but there will be somewhere in the UK who can offer it.

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Re: Porous head?

Post by stevieturbo » Wed Dec 26, 2018 8:25 pm

9.85 @ 144.75mph
202mph standing mile
http://www.youtube.com/watch?v=XgWRCDtiTQ0

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Re: Porous head?

Post by kokkolanpoika » Thu Dec 27, 2018 6:56 pm

Image

Slightly more time to look at those holes.
Look like they are approx 1-2mm deep and very small.
Have to tig weld those.

IF SOMEONE IS INTRESTING. THOSE ARE NEW WILD CAT HEADS WITCH I BOUGHT 2017.. Just start to finishing heads, and surprise.. argh.. Also i have got similar problem to inlet port to head bolt hole. But hole is bigger an it is welded now.

Also like to hear opinion, do i have to replace valve seat if weld those holes.? Another machine shop say maybe. And another say no. At least leak test and maybe machining if needed..
Timo

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stevieturbo
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Re: Porous head?

Post by stevieturbo » Fri Dec 28, 2018 5:36 pm

Speak to specialists who do the laser welding.

Although replacing seats isnt the end of the world, it just adds more cost.

I'd think just TIG'ing it would impart more heat as it's a slower and slightly more widespread process ? So more risk of seats needing re-done. But I'm sure it would also be a good repair.
9.85 @ 144.75mph
202mph standing mile
http://www.youtube.com/watch?v=XgWRCDtiTQ0

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Re: Porous head?

Post by kokkolanpoika » Sat Dec 29, 2018 11:38 am

Forgot to say. That we are finding best solution to repair those heads in Finland and also seller try to do his best. Process is still in progress. Thanks for seller also..
Hope we can repair it..
Timo

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Re: Porous head?

Post by unstable load » Sat Dec 29, 2018 11:51 am

kokkolanpoika wrote:
Sat Dec 29, 2018 11:38 am
and also seller try to do his best. Process is still in progress. Thanks for seller also..
Can't the seller do a swap for a good one?
Cheers,
John

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Re: Porous head?

Post by Ian Anderson » Sat Dec 29, 2018 5:14 pm

What about something like silver solder.

Not a lot of heat required to do that and once sandwiched with a gasket probably zero chance of it coming out

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Re: Porous head?

Post by unstable load » Tue Jan 01, 2019 3:01 am

In all fairness, Ian, something like A4 Metalset will probably work, too.
There is no water around there as long as the gasket is intact, but for a new head I'd be loath to have to resort to that.
Cheers,
John

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Re: Porous head?

Post by kokkolanpoika » Thu Feb 14, 2019 5:03 pm

Image

Image

Image

After welding and cleaning valve seat holes we found a hole after 0.1mm machining.


Those heads are x rayed and pressure tested. :)

Top quality heads.

Also friend of mine has got loose valve guide holes..

Buyers beware.. :)
Timo

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Re: Porous head?

Post by Eliot » Tue Feb 19, 2019 3:41 pm

What a crock of shite.
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Re: Porous head?

Post by kokkolanpoika » Fri Mar 15, 2019 8:05 pm

Head has been welded again. And now machined and new seat fitted.. + pressure tested.
Better than new one. Seller try to compensate only 4x inlet valve seats. But thats nothing. And they wont eaven response when i send pick of valve seat hole problem.. quite poor..

Also if we compare OE heads. OE casting have got more metal under the valve seat. Mutch stronger casting on that place. Also you cannot cut/port seat throat/bowl any more bigger than it is. Because port wall thickness will limit that.. Maybe couple of tenth millimetres.

If use 1.94" valves 90% throat is risky to use, 87% is way to go. You may have then 2.5mm alloy on port wall to water jacket if use 90% rule..
So speech for metal is only speech.

Like Friend on mine says when he compare Merlin head casting to wild cats, that they look mutch better..
Timo

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